# NUMOBAMS 8x16 (NU-210G) Lathe Review



## opensourcefan (Apr 25, 2022)

This is a follow-up to my 8x16 Lather Buyers Guide located here - 8x16 Metal Lathe Buyers Guide | Canadian Hobby Metal Workers & Machinists

*Machine Choice*

Numobams – (IMPERIAL) NU210-G. 8X16 Lathe with reverse threading gearbox. Their website states the following: “_NUMOBAMS NU210-G High Quality 750W Brushless Motor with Postive & Reverse Auto Feed Function Mini Metal”_
The closest cousin to this machine would be the Grizzly GO768 however it has a lower watt motor and a smaller spindle bore. It does however come with a 4 jaw chuck and steady rests which the Numobams did not and needed to be ordered separately.

A side note: Since this purchase a “Semi Automatic” 8x16 lathe has been added which electronically controls the lead screw via a stepper motor. This of course removes any need to gear the lathe and gives infinite possibilities for threading as well as auto feed. Not something I would have chosen due to more electronics to fail and me being an older manual guy but a great choice for many. Probably will become the norm in the very near future.

Warranty – The only implied warranty is for a complete replacement of the control board if it fails within 180 days of delivery. Original must be returned. You may be able to force something through PayPal if you’re within 180 days as well.

Specs in ‘mm’







*Added Accessories (not included with lathe)*

Steady Rests
4 Jaw Chuck
Threading Dial
Multifix style (A) Tool Post kit. (Create Tool maybe) - This (A) size was chosen to take with me to a future lathe. The (A) kit comes with the 90mm wide (AD2090) tool holder. A better fit for this lathe would be the 75mm wide (AD1675).

*Conclusion*

Yes, let me put the end at the beginning to help make all of this clear and to save you time. I learned something with this experience, and that is... manage expectations. Most of the 8x16’s have a lot of shortcomings and deficiency's. This has considerably less but still has some. I was expecting very little to none. I was aware that it was a possibility but I thought, for some reason, that this one was going to be different based on my dealings with the company. In all fairness it probably is 100% in their books but considering all the deficiencies that is my 50% where the other lathes would have most likely been around 30%.

The lathe I received could have been good lathe out of the box if more care was taken during assembly. It is probably one of the better collection of parts that form a 8x16 lathe, but of course the damage, severe headstock misalignment and the worlds worst feeling 3 jaw chuck. The chuck was used on this lathe to keep the overall cost down as it has many other higher end parts, so I was told when I questioned it. It isn’t the higher end “Sanou” brand but something less. Sadly the 3 jaw is an integral part of a lathe, having it on this lathe diminishes the entire package BUT... It’s runout is only .0015 consistently, how can I complain about the feel when it’s this good?? It really does feel bad and how it could have been used during testing and not flagged as such goes to show the what was believed to be acceptable. This probably goes hand in hand with the damaged ways, spindle threads and oil fitting, oh and the missing steady and follow rests that I ordered.

The headstock was out resulting in a .010” taper at only 3” length, can you imagine at it’s full 18”. That is something I would hope would be addressed at the factory since it will require almost a complete disassembly to adjust. Two of the four bolts holding the headstock on are buried in the back.

The rear spindle bearing is also heating up rather quickly. Maybe too much preload or maybe a bad bearing.

They are sending me the missing parts and damaged oil fitting. *They stated that I would need to pay duty etc on those parts!* I stood my ground and said no, it wasn’t my responsibility and they agreed. Just like when you have an issue on auction sites they try and see what they can get away with before they actually do what they should be doing. As far as headstock being out and the rear bearing they, don’t seem to care. 

_I am currently trying to sort out the headstock alignment issue with the Numobams but they are resistant. They are blaming the taper on everything else and actually said I should use the tail stock to straighten the piece!!!!!_

Okay, so back to beginning...

*Preface*

As you know I spent quite a bit of time researching the 8x16 lathe purchasing options. I eventually purchased one from China and had it shipped via boat which was subject to all the shipping issues that the world is currently facing. This review will be of the initial observations of the lathe, a small amount of operation and the company themselves. I long term update to this review will be posted once I put a sufficient amount of operating time into it.

*Price*

This is a bit difficult to determine as I received many discounts from advertised prices and the prices seem to be all over the place. The total was around $1660 USD for all above including shipping. $1210 USD for just the lathe and extra bits. The only surprise was an increase in shipping cost of $100 USD extra.

The Grizzly equivalent, GO768 would have been $1695 USD + $299 Shipping to Canada not including duty and taxes at the border. Including the tool post the total savings were in the neighbourhood of $700 - $800 USD. If you’re in the US do the conversion, In Canada, every US dollar saved is good, very good. Important to note that the spindle bore diameter is only 20mm with the Grizzly. My very first project required 25mm round stock that I fed through my 38mm bore. This is a big deal I think and reduces the constant reminder that you’re using a mini-lathe.


*Purchase Experience*

I first found the lathe on Aliexpress and sent a message inquiring. I was contacted by Sam from Numobams. I was directed to their own website to browse. Their website showed most of their products but it wasn’t as straight forward as it could have been.
*NUMOBAMS* < Link
The website is full of major grammatical errors. Their own website name is even misspelled. However like most of the shopping experiences from the far east this is to be expected. Communicating via email however was much easier and their English was much better.

Sam (samli@numobams.com) was my contact there and his email is provided on the website. It appears all communication goes through him as in my billion emails back and forth I never chatted with anyone else. He was great to deal with.

If your purchase is simple as choosing and hitting buy on the website then it will be easy. If communication and order tweaking is necessary there may be some frustration. Also keep in mind, as eluded to above, their customer service isn’t really centric to the customer.

*Time Time Time...*

Below you’ll see my timeline. _TLDR – It took forever!_ If you can’t handle a multi-month delay then this isn’t for you. There isn’t a distributor anywhere near me so direct from China was the only option for this specific lathe.

There was about a 3 to 4 week delay caused by me due to confirming the ‘Imperialness’ of the machine. I ensured that all the required gearing was supplied to cut the most common Imperial threads. This wasn’t very easy for them as this machine has the larger spindle so it’s not quite the same as copying the Grizzly setup. None the less they were able to do it while maintaining a very close accuracy with the Metric threads as well. The entire lathe is Imperial, this is important as many of the Imperial options of your typical 8x16 usually just have the dials changed. Even the tailstock quill shows inches.

If I had chosen a metric lathe off their website and just ordered with no add-ons or questioning emails, it all would have been about 4 weeks faster. Not much now in the scheme of things really.

2021 Nov 6th – First contact
2021 Nov 9th – Ordered and paid
2021 Nov 10th to the 28th – Sorting out the gearing for threading
2021 Dec 12th – Awaiting container
2021 Dec 29th – Advised shipping cost increased, added funds. $100 USD
2022 Jan 6th – Ship departed for Vancouver, BC with a couple Asian stops along the way.
2022 Jan 31st – Arrives off the coast of Vancouver Island and anchors awaiting slot in port with a date of Feb 6th.
2022 Feb 6th – Port date changed to Feb 28th
2022 Feb 10th or so – Port date changed to Mar 10th.
2022 Feb 25th – Port date changed to Mar 16th.
2022 stopped paying attention...
2022 March 19th – Arrived at the Vancouver Port.
2022 March 31st – Ready for pickup at the warehouse
2022 April 1st – Finally got my lathe!!!!!!

*Eyes on the Product*

It came packed in a very well built crate.





The warehouse staff helped me load it into my vehicle.

Popped the top off while still in the vehicle to remove access weight for easier moving.





There it is, with all the extra bits. It was bolted to the crate obviously, the tail stock was locked, the carriage and post were locked into the chuck jaws to prevent rotation and movement. No handles were bent or broken which was a concern due to all the heavy extras floating around in the crate.

Before you freak out, I was given a color option at the time of ordering but this is their signature color and I felt like being different.






So after researching these 8x16’s in an OCD fashion, I immediately noticed that this lathe looked better vs the others. It is quite similar to the Grizzly in build I would say.

Things of note: The gear table was specifically made for me and for this machine. I wanted all the threading options like the Grizzly, so they had the sticker custom made to suit. They also supplied all the extra gears at no extra cost. Excellent service on their part helping me through all of this. The threading dial and sticker were installed on the machine.

So being a large bore machine (38mm), it also came with a 38mm bore 3 jaw chuck (more on that chuck later).




You can see some decent metal gears stamped with the tooth count.

You can also see a safety cutoff switch in case the panel comes loose or you try and stick your fingers in.

It’s a bit oily and dirty in there from the testing.


*Initial Inspection*

Good (comparing to other 8x16 lathes)
Seems to be built with better than average parts
Paint and casting finishing is good (see above photos)
Panel gaps are even and straight (see above photos)
Stainless hardware (gib and panel screws)
Control Board heat-sink – This is something new to me, haven’t seen it on any 8x16 before. Being an electronics guy I always love to see the dissipation of heat in circuits and designs. This is something that the Grizzly doesn’t appear to have either. Just to confirm, I had to see if anything was actually mounted to the heat-sink.









Yes the panel came missing a screw. Looking at the board though I can see the capacitors are 105 degree which is good. They are also potted to protect them from vibration. The Mosfets are all mounted on the underside of the board to make use of the heat-sink. There are a lot of old school through hole components which will make this easier to diagnose and repair. Seems like a thoughtful design.


Bad
- Steady and Follow rests missing, adds another month or two to have a complete lathe.
*- Damage on the ways
- Damage on Spindle thread
- Oil fitting damaged
- Headstock out of alignment
- Rear spindle bearing heating up*
- Screw missing on back heat sink
- Gear spacers missing for all gear setups
- Gears not properly meshed, making a racket while running
- Compound not smooth due to bent gib
- 3 Jaw chuck is low quality, definitely the lowest quality item on this lathe


*WAY DAMAGE*

Damage was caused after the bed grinding as I was able to find high spots around the dents.











*SPINDLE THREAD DAMAGE*






Again the damage was caused post nut install as the threads are still mashed over and not cleaned by the nut install.

*OIL FITTING DAMAGED*






I popped it back out but anytime you touch it gets stuck again. Spring inside must be all wonky.

There was just so much carelessness with this lathe during all the testing. I was afraid all the testing to make sure it was Imperial increased the risk, I should have known better.

*3 JAW CHUCK POOR QUALITY*

The 3 jaw chuck was awful. The jaws were hard to move, it felt like something was grinding itself up upon moving any of the jaws and I could see brass and other debris all over it. I pulled it off and it looked like this:










Yes, all those extra holes in the back cover AND casting!!! were there along with all those leafy looking bits of who knows what. I have no idea how this chuck made it to market and on this lathe. Zero quality control.






Teeth full of metal shavings. 
I took it apart, cleaned and deburred and cleaned some more. It’s about 85% now. There are a couple tight spots near closing, run out is consistently .0015” which is a bonus I guess.

When I questioned Numobams about the chuck quality, I was advised that it was a cost saving measure. In my opinion it’s a great way to diminish your products credibility.


*OPERATION*

I got the chance to use the lathe to build the Multifix Toolpost fittings required to fit onto the stock toolpost post. I wanted to make sure that I could easily revert as the Multifix will come with me to the next lathe.




The carriage and cross slides are smooth and tight. The compound needs help. The travel is loose in the middle and tight on each end obviously. For now I’ve just tightened it up until I need to move it.

I don’t like the gearing of the carriage wheel, 1” per revolution which is too much for me.

The slowest I can gear the autofeed down to is .006”/rotation. The Grizzly can get down to .0037” due to it’s smaller drive gear which I think is much better for this lathe’s ability. I’m going to work on some mods to maybe get close to that if possible.

CONTROLS

The controls are the same as most other 8x16’s. On/Off, fwd/neutral/rev, variable speed. This machine has a gearbox to switch the direction of the lead screw for left hand threading. The biggest plus of this gearbox is that I can deactivate the lead screw which reduces a bit of load on the motor, makes it a bit quieter and reduces unnecessary wear on the lead screw hardware.

UNDER LOAD

Upon changing the load on the machine while cutting I can briefly see a drop in RPM and a ramp up of the motor which is getting more power to provide more torque. I’m guessing the control board delivers only as much power that is currently needed and no more to prevent overheating and wear. This of course is not ideal when in the middle of a cut as it is impossible to maintain the same finish, at least I can’t. I like the idea but I wish it was twice as fast to cycle up.


*THE END*


Overall I totally regret making this purchase. 

What would you do if this was your experience?


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## David_R8 (Apr 25, 2022)

Oh man, that so reminds me of my first lathe, a 7x12 mini lathe. It too was chock-a-block full of issues to the point where I cut my losses and resold it. I did get some cash back from the eBay seller because it did not have a brushless motor as it was advertised as having.

Were it me, I'd file a claim and send that sucker back.


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## Tom Kitta (Apr 26, 2022)

Feels like getting some used old iron would be far better choice - that is ... a lot of issues for a brand new lathe. Usually Chinese lathes have some issues but not a whole family out of the box.


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## opensourcefan (Apr 26, 2022)

Tom Kitta said:


> Feels like getting some used old iron would be far better choice - that is ... a lot of issues for a brand new lathe. Usually Chinese lathes have some issues but not a whole family out of the box.


Yes and it's touted as being one of the best model 210 lathes. They just don't understand that the sum of the parts alone don't automatically make a good product.

I'm still thinking about something old and heavy but I need small.


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## David_R8 (Apr 26, 2022)

If you can find an older South Bend 9A or 10K you'd be well served. I take you you're in the lower mainland?


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## DPittman (Apr 26, 2022)

opensourcefan said:


> Yes and it's touted as being one of the best model 210 lathes. They just don't understand that the sum of the parts alone don't automatically make a good product.
> 
> I'm still thinking about something old and heavy but I need small.


It appears you haven't had the best of luck with your Asian lathe experience so far but I don't think you should completely give up yet.  Old decent machinery in small and affordable packages are hard to find.  While most of the Asian lathes could be vastly improved at the factory with just a bit more expenditure in time and materials, they are still a pretty dang good bang for the buck.  Considering the price I paid and the features of my BusyBee lathe, I have been very happy with it.


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## opensourcefan (Apr 26, 2022)

David_R8 said:


> If you can find an older South Bend 9A or 10K you'd be well served. I take you you're in the lover mainland?


Yep I am. Hard to find one of those.


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## opensourcefan (Apr 26, 2022)

DPittman said:


> It appears you haven't had the best of luck with your Asian lathe experience so far but I don't think you should completely give up yet.  Old decent machinery in small and affordable packages are hard to find.  While most of the Asian lathes could be vastly improved at the factory with just a bit more expenditure in time and materials, they are still a pretty dang good bang for the buck.  Considering the price I paid and the features of my BusyBee lathe, I have been very happy with it.


The BusyBee 10x22 is where I may go if this falls through.


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## David_R8 (Apr 26, 2022)

opensourcefan said:


> Yep I am. Hard to find one of those.


Something I did that was to place an ad saying you are looking for a lathe. I had a couple of good leads from the ad.


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## PaulL (Apr 26, 2022)

opensourcefan said:


> The BusyBee 10x22 is where I may go if this falls through.


I recently got the Busy Bee 12x26.  I've not had any problems similar to what you've reported on your lathe - overall I'm pleased with it, especially now that I know how to run it a bit better.


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## chip4charlie (Apr 26, 2022)

Thanks for posting your comprehensive review.


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## John Conroy (Apr 26, 2022)

For the rear bearing heating problem it could just be too much pre-load on the bearing. That machine probably has tapered roller bearings at both ends of the spindle. The 2 nuts (in the picture that shows the damaged threads on the spindle) control the preload on that rear bearing . I would back those nuts off and reset the preload. Tighten the inner nut until the end play in the bearing is gone, then add a tiny bit of preload. The outer nut is just a jamb nut, make sure the inner one doesn't turn while you tighten the outer


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## Proxule (Apr 26, 2022)

Sigh....... Sigh!
Sorry my friend.


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## opensourcefan (Apr 27, 2022)

John Conroy said:


> For the rear bearing heating problem it could just be too much pre-load on the bearing. That machine probably has tapered roller bearings at both ends of the spindle. The 2 nuts (in the picture that shows the damaged threads on the spindle) control the preload on that rear bearing . I would back those nuts off and reset the preload. Tighten the inner nut until the end play in the bearing is gone, then add a tiny bit of preload. The outer nut is just a jamb nut, make sure the inner one doesn't turn while you tighten the outer


I did just that and it helped some. I think they just ham fisted the nuts.


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## Susquatch (Apr 27, 2022)

opensourcefan said:


> What would you do if this was your experience



Wow. I put a love on your post because of the work you did to write the post. I wanted to put an angry face to reflect your experience. 

What would I do if this was my experience? Well, I'd never have the guts to order a whole lathe from Ali so I won't ever have that experience. 

That said, I'd go after Ali, as well as paypal. Ali seems to care about customers more than PayPal. And my experience is that the vendors are not afraid of PayPal but they are terrified of Ali. 

Much as you like the salesman, they still sent you junk. I'd make sure that he knows that you expect to get looked after. 

A question for you - are you gunna try and fix it?


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## Chicken lights (Apr 27, 2022)

Susquatch said:


> Wow. I put a love on your post because of the work you did to write the post. I wanted to put an angry face to reflect your experience.
> 
> What would I do if this was my experience? Well, I'd never have the guts to order a whole lathe from Ali so I won't ever have that experience.
> 
> ...


China is a touchy subject around this forum  

Personally, I won’t go out of my way to support that country. I realize it’s next to impossible to not buy China origin products

China can probably manufacture quality goods (and do so already) but the majority of what they produce is crap (unless specced otherwise)

Given your background in automotive R&D, what’s your comments on Asian influence on safety measures/quality control on most products?


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## opensourcefan (Apr 27, 2022)

Susquatch said:


> Wow. I put a love on your post because of the work you did to write the post. I wanted to put an angry face to reflect your experience.
> 
> What would I do if this was my experience? Well, I'd never have the guts to order a whole lathe from Ali so I won't ever have that experience.
> 
> ...



I would like to fix it. Really it's just aligning the head to get it running. The rear bearing is better now that I took the 900ft/lbs off of it. 

Overall it was just a very disappointing experience. After all the waiting having to go through this...  And then having the seller who I truly believed was better than the rest turned out to only be 33.33% better.

If I go through PayPal and they side with the seller I will lose my nut. My wife read some of his emails and she is really po'd, she just wants me to end this. 

You guys have been such a help and kept me somewhat sane during all this, I thank you all for that!


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## opensourcefan (Apr 27, 2022)

Chicken lights said:


> China is a touchy subject around this forum
> 
> Personally, I won’t go out of my way to support that country. I realize it’s next to impossible to not buy China origin products
> 
> ...


If I was on the east coast I would have purchased something good and old. Out west though our options are very limited for something small. Although taking hindsight into account, I'd be willing to spend more now


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## Degen (Apr 28, 2022)

I'm going to say you saved a ton of money and complain about a chuck?

Sounds like Rolls Royce expectations on a LADA budget.

Don't get mad yet on my comments, I here to give you an inexpensive solution to put a smile on your face. 

Scrolling 3 jaw chucks are good for roughing and even with good ones run out is going to be an issue, nature of the beast. Instead of wasting energy complaining (and getting your BP up) by getting stressed about it, do the machinist thing and come up with a solution. Heres a simple one  that only costs you 4 set screws and some time and gives you precision chuck.






You saved a ton, learned something new and can afford more equipment with the money you saved.....Life is only as good as you see it.


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## Susquatch (Apr 28, 2022)

Chicken lights said:


> Given your background in automotive R&D, what’s your comments on Asian influence on safety measures/quality control on most products?



This is actually a subject I enjoy talking about on all levels.

I've personally visited most Asian countries. They have their challenges, their advantages, and a very different outlook on life - politically and socially. I do not know why discussing it needs to be sensitive. Even among our membership we have different opinions and preferences. Some place more value on pure cost, some on quality, some on availability, some on performance, most of us place value on all these things to different degrees. China is a long ways away. Given all other things equal, I'd rather buy local. In fact, I'd rather pay more to buy local even if it originally comes from China. But I don't like to get ripped off. A fair markup to cover faster availability and a hassle free experience is perfectly ok with me.

Back to your questions.

First Car Quality - it used to matter - It doesn't much matter anymore. Japanese and South Korean car quality is second to none. Chinese vehicle quality - well, not so much. I think the best comparison I can make is to compare Chinese auto manufacturing to R/V manufacturing in North America. It can be really nice stuff with lots of features but man are they ever rough around the edges.

An interesting story worth telling is "perception". A study was done on a product made in a North American Assembly plant but sold in both Asian and Domestic dealerships both overseas and in N. America. The warranty costs were 10 times higher for the N. American branded product even though they were totally identical in every respect except the name badge. How could that be? According to JD Powers the difference was mostly customer expectations - the buyers accepted the Asian quality but demanded better from N America. There was also a little dealership revenue generation going on too...... 

Then there is progress. Each generation of product gets better and better no matter who makes it. But when someone has a bad experience with Honda, and then buys a much newer car from Toyota, they get a better car. So they automatically assume that Toyota is better and swear they will never buy another Honda. But the equivalent new Honda is much better than the old one was and probably just as good as the new Toyota.

Safety is a whole nuther subject. I've discussed that here before. There are government safety standards which are mostly tests to meet minimum standards. Vehicles either meet them or don't. If they meet them, they are certified for sale to consumers. But then there are also internal goals. To take a simple example, consider a head injury criteria in a barrier Impact test. Government requires a maximum injury rating for a frontal impact. Industry tests and certifies this performance level. But industry goes WAAAAYYY beyond that. Computer simulations allow the industry to test and calibrate those tests in the real world to a million (actually a continuum) of other scenarios at every conceivable angle and speed to maximize "real world" safety. Ironically, sometimes the mandated tests limit what could have been achieved without them.  There are no standards for this. Companies just do it because they can. Real world accidents don't follow the rules. Yet government, the media, and consumers only look at the regulated numbers and the ratings. 

At the same time, there are some very important differences in how these "real world" factors are developed. Highway infrastructure, driving regulations, and driving habits in North America, China, Japan, Europe, India, Africa, etc etc are all very different. It's not possible to optimize performance for all these differences simultaneously in the same vehicle. Knowing this, I prefer to buy vehicles that were predominantly designed for the North American market because that's where I drive. Note that I said "designed for", not "built in".

One last comment on safety. *SIZE MATTERS*. It's pure physics.

I could go on and on for days on this subject. But I think that's enough for one post. Happy to answer more questions.


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## Chicken lights (Apr 28, 2022)

Susquatch said:


> This is actually a subject I enjoy talking about on all levels.
> 
> I've personally visited most Asian countries. They have their challenges, their advantages, and a very different outlook on life - politically and socially. I do not know why discussing it needs to be sensitive. Even among our membership we have different opinions and preferences. Some place more value on pure cost, some on quality, some on availability, some on performance, most of us place value on all these things to different degrees. China is a long ways away. Given all other things equal, I'd rather buy local. In fact, I'd rather pay more to buy local even if it originally comes from China. But I don't like to get ripped off. A fair markup to cover faster availability and a hassle free experience is perfectly ok with me.
> 
> ...


We’re getting off topic again- while I haven’t driven in Mexico, or the Territories, there is not much in the way of uniformity on North American infrastructure or driving habits 

I do agree on size matters (for vehicles) and am constantly baffled at people that play (bad word) games in front of large trucks. In general the USA drives larger vehicles than Canada, you actually don’t see mini vans very much in the south it’s mostly pickup trucks. There has to be a demographic for auto manufacturers by state/country for vehicle popularity?

I would guess, most asian and European countries prefer smaller vehicles so the North American market is unique


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## thestelster (Apr 28, 2022)

Degen said:


> I'm going to say you saved a ton of money and complain about a chuck?
> 
> Sounds like Rolls Royce expectations on a LADA budget.
> 
> ...


I don't think a set-thru chuck will fix his problem.  His chuck run-out is only .0015".  The set-thru chuck only addresses run out.  It's basically a 3jaw chuck, with 4 jaw capabilities.  The two parts of the set-thru move in the same plane/parallel to each other.  If the head is angled relative to the bed ways, it will still cut a taper.  The only way to fix the taper cutting issue is to either, 1. align the head to the ways, or 2. use an 8-jaw spider set up, but that is very inconvenient except for special applications.


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## GummyMonster (Apr 28, 2022)

OP -
 That really sucks that you are so unhappy with your lathe. I would definitely file a claim with AliExpress. I had to do this once with a rifle scope that had flaws on the inside of the lens. It is useable but distracting until you can get used to it. The seller offered me something ridiculous like $5 off, because it technically functioned properly. I wrote Ali, and I was given a full refund and told to keep the scope within 1 day.
 AliExpress is so big, they won't risk getting any bad feedback on the interweb over what is a minuscule amount of money to them.
I'd start there. But be prepared to deal with translating the discussion. I've bought a lot of stuff from China, and I can tell just by how ads are written if it's a Chinese seller (on Amazon and such)
  I assume it's due to using a translation program, and some words that just don't totally translate between the 2 languages.
Good luck and don't give up.
Ken


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## GummyMonster (Apr 28, 2022)

I actually have virtually the same lathe. I picked one with DRO's and a 850w motor.
 I had issues getting it here, this was about 1 year ago when covid was changing the shipping industry constantly. Sam actually gave me an extra 4 jaw chuck to compensate for the added cost and wait times. It was very frustrating, but I looked into the things he was telling me about shipping, and he was being 100% forthright. As the pics show, I also bought a milling machine with DRO's. It is blue, which annoys me since I actually like the bright colour. But some paint will fix that.
 To be fully honest, I haven't done any machining with either yet. Life this past year has been very difficult for me and the people I love, so machining parts hasn't been high on my list. The desire to has, but life keeps getting in the way. It's looking like that will be changing soon, as setting them up is very close to the top of my to do list.
 I have however, partially disassembled them for moving between buildings. While doing so I turned and worked every piece I could. I've worked on all manner of mechanical things in my life, and I am actually very happy with the build quality.
 No flaws that I've seen, and everything turns, moves extremely smoothly.
 It was actually better than my expectations.
The milling machine follows suit.
As far as accuracy, I can't say yet, but the build quality leads me to believe it will be decent.
 So my experience was almost totally opposite yours.
 Please don't get offended, but were your expectations a bit high possibly? The fellows on here told me to set my expectations properly before I purchased. Ordering unseen (in person) equipment from China is a bit of a gamble, but the prices justify that gamble.
  If I may ask, why go to all the trouble of getting them to convert it to SAE. Virtually Everything from overseas is metric, so they were probably working with parameters and calculations totally foreign to them in the factory (word play there on purpose). 
 Either way, it's your business, and I hope your experience ends up satisfactory.
With the market still short on stock, I wouldn't be surprised if you could sell it even with the issues for a really decent price. As you stated, out west here, these type of machines just aren't commonly available. If AliExpress gives you a partial refund, you may end up recovering your investment.
Good luck,
Ken


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## DPittman (Apr 28, 2022)

Well if you end having to (or choosing to) keep the lathe, I'm pretty sure the forum can help and guide you into making your lathe and accurate and useable machine.


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## chip4charlie (Apr 28, 2022)

OSF, I'm also in the Lower Mainland (White Rock). I have an Edge Technologies Tailstock Alignment Bar you can borrow if you like. Used it on my Vevor 7 x 12 as the tailstock was out by 3.5mm ...









						Tailstock Alignment Bar 27-000
					

The Tailstock Alignment Bar by Edge Technology is used to align the tailstock to the headstock. Accurate alignment is critical to eliminate any taper in work pieces that are supported by the tail stock. Our Tailstock Alignment Bar makes the process of tailstock alignment fast, easy and accurate.




					www.edgetechnologyproducts.com


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## Rauce (Apr 28, 2022)

Does the spindle have an internal Morse taper? A Morse taper test bar will tell you for sure if it’s headstock alignment. They’re fairly inexpensive and useful for tailstock alignment as well.


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## opensourcefan (Apr 28, 2022)

GummyMonster said:


> OP -
> That really sucks that you are so unhappy with your lathe. I would definitely file a claim with AliExpress. I had to do this once with a rifle scope that had flaws on the inside of the lens. It is useable but distracting until you can get used to it. The seller offered me something ridiculous like $5 off, because it technically functioned properly. I wrote Ali, and I was given a full refund and told to keep the scope within 1 day.
> AliExpress is so big, they won't risk getting any bad feedback on the interweb over what is a minuscule amount of money to them.
> I'd start there. But be prepared to deal with translating the discussion. I've bought a lot of stuff from China, and I can tell just by how ads are written if it's a Chinese seller (on Amazon and such)
> ...



Sam directed me to his website and everything was purchased from there, I'm not sure Ali can help in this situation?



GummyMonster said:


> I actually have virtually the same lathe. I picked one with DRO's and a 850w motor.
> I had issues getting it here, this was about 1 year ago when covid was changing the shipping industry constantly. Sam actually gave me an extra 4 jaw chuck to compensate for the added cost and wait times. It was very frustrating, but I looked into the things he was telling me about shipping, and he was being 100% forthright. As the pics show, I also bought a milling machine with DRO's. It is blue, which annoys me since I actually like the bright colour. But some paint will fix that.
> To be fully honest, I haven't done any machining with either yet. Life this past year has been very difficult for me and the people I love, so machining parts hasn't been high on my list. The desire to has, but life keeps getting in the way. It's looking like that will be changing soon, as setting them up is very close to the top of my to do list.
> I have however, partially disassembled them for moving between buildings. While doing so I turned and worked every piece I could. I've worked on all manner of mechanical things in my life, and I am actually very happy with the build quality.
> ...



It is good to know that you had a better experience. 
I don't blame them at all for the time it took, I caused the delays at the factory and boats will be boats. 
The only expectations that I had was to get an undamaged machine that was accurate enough to use. .005" within 3" is not that. I got a machine with damage, missing parts and that was inaccurate, is this too high of expectations...?  
re SAE... I'm not young, I've spent my life working with SAE on aircraft and turbine engines. It wasn't a full conversion, they have an SAE line. I just had them ensure everything was actually SAE and that I was able to build the gearing to cut the SAE threads. Basically I wanted them to meet the specs of the Grizzly lathe. 

I don't think my expectations were high in regards to the machine. I will admit my expectations have always been high on people and their integrity and accountability. 



chip4charlie said:


> OSF, I'm also in the Lower Mainland (White Rock). I have an Edge Technologies Tailstock Alignment Bar you can borrow if you like. Used it on my Vevor 7 x 12 as the tailstock was out by 3.5mm ...
> 
> 
> 
> ...



Thank you so much for the offer, I may take you up on it if I can't find a spindle bar.



Rauce said:


> Does the spindle have an internal Morse taper? A Morse taper test bar will tell you for sure if it’s headstock alignment. They’re fairly inexpensive and useful for tailstock alignment as well.



Yes, it's an MT5. Obviously being an MT5 it's more expensive.


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## DPittman (Apr 28, 2022)

opensourcefan said:


> Sam directed me to his website and everything was purchased from there, I'm not sure Ali can help in this situation?
> 
> 
> 
> ...


Wow mt5 is HUGE for that size of lathe.

Don't all lathes have a morse taper spindle (obviously not or else you wouldn't have asked) I'm just curious what else is out there?


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## opensourcefan (Apr 28, 2022)

DPittman said:


> Wow mt5 is HUGE for that size of lathe.
> 
> Don't all lathes have a morse taper spindle (obviously not or else you wouldn't have asked) I'm just curious what else is out there?


Yes, it's considered a "large bore" 8x16. Super handy feature. Very first project made use of it. Grizzly is MT3

It comes at the cost of more expensive tooling though.


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## DPittman (Apr 28, 2022)

opensourcefan said:


> Yes, it's considered a "large bore" 8x16. Super handy feature. Very first project made use of it. Grizzly is MT3
> 
> It comes at the cost of more expensive tooling though.


Yes I guess headstock accessories would be more expensive but man that IS a nice feature that I would think would be worth it.


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## Rauce (Apr 28, 2022)

DPittman said:


> Wow mt5 is HUGE for that size of lathe.
> 
> Don't all lathes have a morse taper spindle (obviously not or else you wouldn't have asked) I'm just curious what else is out there?


 
Most do, but I don’t think it’s universal. I know of at least one lathe we have at work that has a proprietary internal spindle taper that you need a special reducer to put a center in.


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## Tom Kitta (Apr 28, 2022)

opensourcefan said:


> The BusyBee 10x22 is where I may go if this falls through.



Busy bee machines are not great not terrible. Certainly they will have less issues then what you got, but they are still cheap China, not some premium - they compete on price and price alone. Decent older machine would be a far better choice.


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## David_R8 (Apr 28, 2022)

@Tom Kitta unfortunately smaller machines are rare as hens teeth where @opensourcefan lives


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## Tom Kitta (Apr 28, 2022)

Susquatch said:


> This is actually a subject I enjoy talking about on all levels.
> 
> I've personally visited most Asian countries. They have their challenges, their advantages, and a very different outlook on life - politically and socially. I do not know why discussing it needs to be sensitive. Even among our membership we have different opinions and preferences. Some place more value on pure cost, some on quality, some on availability, some on performance, most of us place value on all these things to different degrees. China is a long ways away. Given all other things equal, I'd rather buy local. In fact, I'd rather pay more to buy local even if it originally comes from China. But I don't like to get ripped off. A fair markup to cover faster availability and a hassle free experience is perfectly ok with me.
> 
> ...



I also been to most Asian countries, if counting my parents we only miss few, like Afghanistan. 

I do not see South Korean as good quality at all - they are lesser then US made cars. You can have 2015 Kia SUV for like 6000 CAD with leather interior. They disintegrate after just 100k miles. 

Chinese cars are not bad! Most US makes exist in China - even some rather obscure in US - like Buick. China is by far the world's largest manufacturer of cars and largest car market. They have lots of companies fighting for it - more fractured then US. Competition is very fierce. I would not be shocked to have Chinese car outlast anything made in US or Canada. 

Driving habits in say China are totally different then Chinese driving habits in say Canada. Your average middle aged office worker woman from tire 1 city in China could do better parking job then 99% of people in Canada / US. Also vehicles are frequently pushed way, way, way harder. 

One has to note that a lot of Chinese, going back to machinery, do not buy based on price point but quality. So no, frequently Chinese would not use same tools, machines, etc. they sell for export at home. I.e. Chinese lathe in China can do circles around Chinese lathe in US. They are not the same model. 
This is not true for all stuff - I saw in China identical thermos sold in Walmart in Canada - so both Chinese and US markets got same stuff. But with some tools I saw it was certainly true.


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## Tom Kitta (Apr 28, 2022)

Rauce said:


> Most do, but I don’t think it’s universal. I know of at least one lathe we have at work that has a proprietary internal spindle taper that you need a special reducer to put a center in.


It may be MT 4.5 - smaller older machines have these.

MT5 is huge. This may explain some issues with bearings heating up. Note older 14x40 machines have MT5 - newer machines have MT6.


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## Susquatch (Apr 28, 2022)

Tom Kitta said:


> I also been to most Asian countries, if counting my parents we only miss few, like Afghanistan.
> 
> I do not see South Korean as good quality at all - they are lesser then US made cars. You can have 2015 Kia SUV for like 6000 CAD with leather interior. They disintegrate after just 100k miles.
> 
> ...



I can imagine that what you say about machinery could be true. I do not know.

But I think we must have visited two different China's for cars and trucks. On my last trip to China (after I retired) I was specifically hired as a consultant to inspect and approve the quality, durability, and safety of Chinese made trucks and buses for sale in Canada. They did not measure up. That was just 6 years ago. Prior to retiring 15 years ago, I was also personally involved in the inspection and tear down a variety of Chinese cars. They were also substandard. Now if you are talking about North American and European cars built in China by an American or European car company, that is a whole different subject.

You also say that Korean vehicles are lesser than US made cars as though US made cars are practically the bottom of the heap. Lots and lots and lots of customers say otherwise. 

I think it's best to just agree to disagree on this one Tom.


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## Rauce (Apr 28, 2022)

Tom Kitta said:


> It may be MT 4.5 - smaller older machines have these.
> 
> MT5 is huge. This may explain some issues with bearings heating up. Note older 14x40 machines have MT5 - newer machines have MT6.



It’s a Colchester, I can’t remember the model but it’s around 14x40 in size which makes it practically miniature in our shop at work haha.

Some googling suggests it could be a Jarno taper or maybe proprietary… it’s close to MT5 in size but not the same taper angle.


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## Tom Kitta (Apr 28, 2022)

Rauce said:


> It’s a Colchester, I can’t remember the model but it’s around 14x40 in size which makes it practically miniature in our shop at work haha.
> 
> Some googling suggests it could be a Jarno taper or maybe proprietary… it’s close to MT5 in size but not the same taper angle.



Yep mine is Colchester as well.


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## GummyMonster (Apr 28, 2022)

I hope I didn't offend  you regarding the high expectations comment.
   I just meant that the little things like the marks on the ways and loose/ missing screws aren't something I'd consider a big problem considering the cost savings from buying direct. I'm sure if their QC was a lot better, then the price would be a lot higher.
  As far as the bigger issues like the thread damage and such, I absolutely agree with you that those things aren't acceptable.

 If you first found it on AliExpress, it would be worth contacting them. Sam kind of cut them out when he directed you away from the main site to his. Worse that could happen is that they can't help.
 I hope you get the problems sorted out, because I think you'll have a heck of a good machine if you do.
Ken


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## Susquatch (Apr 28, 2022)

@opensourcefan - your thread came off the rails a bit there and I apologize for my role in that. 

I confess that I am a bit confused. I re-read your entire thread to try and make sense of things. 

Normally, when a lathe produces a taper that close to the chuck, it is not the Chuck's fault unless the chuck is loose. No matter how badly a part is held in a chuck, and no matter how badly the chuck is attached to the spindle, and no matter how out of round the chuck is etc, the part will turn concentric to the spindle, not the chuck. A better chuck will only help hold a part more closely to the axis of the spindle. 

In my mind, there are only three possibilities. 

1. The axis of the spindle is not aligned to the axis of the bed. 

2. The tool holder is moving up/dwn or In/out while it moves on the bed. 

3. The chuck or the part held in the chuck is loose and moving around. 

I expect this might sound like Greek to you, but think about it. With a good lathe that is setup properly, and a really crummy 3 jaw chuck, you can put a chunk of square stock in the chuck, and turn a perfect cylinder with no taper. When the tailstock is not used, tapers at the head only happen when the spindle axis is not aligned with the axis of the tool travel - which should be the same as the axis of the bed. 

You cleaned up that chuck and I think it's probably ok now. 

But I don't think your head and/or ways are aligned properly.


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## Susquatch (Apr 28, 2022)

@opensourcefan - one more thing. As I understand it, this character "Sam" lured you away from Ali to his own website. If that happened on eBay or Amazon, that supplier would be in really big trouble. I'd wager that the same thing applies at Ali. 

This gives you lots of leverage. I'd suggest two things here. Find out what Ali's policies are on that front. If they are as I expect, and if you have copies of his correspondence luring you away, you can have a very different conversation with Sam. If you are pissed off enough, I'd go straight to Ali with that info.


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## opensourcefan (Apr 28, 2022)

UPDATE

Okay so he finally agreed that the head is out of alignment. He is sending me a new Sanou 3 jaw chuck as compensation for the issues and I'm going to fix it.

Saga is over. I feel better now.


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## opensourcefan (Apr 28, 2022)

@Susquatch 

Yep agree, it was always the head alignment, I never believed for a second that it was the chuck but they did. Took forever to convince them otherwise.


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## Susquatch (Apr 28, 2022)

opensourcefan said:


> UPDATE
> 
> Okay so he finally agreed that the head is out of alignment. He is sending me a new Sanou 3 jaw chuck as compensation for the issues and I'm going to fix it.
> 
> Saga is over. I feel better now.



I'm glad you are happier. Do you have a plan yet for how to go about fixing it?  If not, post a few photos of how your head and bed are attached to each other.


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## opensourcefan (Apr 28, 2022)

Susquatch said:


> I'm glad you are happier. Do you have a plan yet for how to go about fixing it?  If not, post a few photos of how your head and bed are attached to each other.


Just 4 bolts behind some electrical housings that need to be pulled. All the electrical needs to be hung out to get that section off.

Going to ever so lightly loosen 3 with the 4th just a touch tighter so when I "tappy tap tap" it'll pivot a bit and not go too far outta whack. 

I'll first use my .001" dial indicator followed up by my .0001". Going to use the bar I last turned which is still undisturbed in the chuck. It'll have to do until I find an MT5 Test Bar.


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## YYCHM (Apr 28, 2022)

opensourcefan said:


> Going to use the bar I last turned which is still undisturbed in the chuck.



Doesn't that bar have a taper since you turned it already?


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## opensourcefan (Apr 28, 2022)

YYCHM said:


> Doesn't that bar have a taper since you turned it already?


Yes

The taper was cut in relation to the ways. If I align the back end of the cut piece it will be aligned with the ways.

I have completed the first round of alignments in the absence of having a longer test bar. I wasn't able to tap it into position as the relationship between the way seats on the head and the bed ways wasn't accurate. Each time I tightened up the bolts it all went to crap again. So I ended up shimming the head both vertically and laterally. It's now  .002" within 4". I can live with that untill I get my bar.

I think this proved that it was built this way and wasn't a bump during shipping or whatever.


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## Susquatch (Apr 29, 2022)

opensourcefan said:


> Yes
> 
> The taper was cut in relation to the ways. If I align the back end of the cut piece it will be aligned with the ways.
> 
> ...





opensourcefan said:


> Just 4 bolts behind some electrical housings that need to be pulled. All the electrical needs to be hung out to get that section off.
> 
> Going to ever so lightly loosen 3 with the 4th just a touch tighter so when I "tappy tap tap" it'll pivot a bit and not go too far outta whack.
> 
> I'll first use my .001" dial indicator followed up by my .0001". Going to use the bar I last turned which is still undisturbed in the chuck. It'll have to do until I find an MT5 Test Bar.



OK, sounds to me like you know what is needed. 

Personally, I'm not a fan of the MT5 test bar method anyway. It depends on a perfectly machined MT5 socket in the spindle and a perfectly machined test bar. 

A solidly mounted chuck and a piece of 1-1/2" pipe 12" long firmly mounted in the chuck will actually work better. Many machinists use an 8 inch pipe, and some even use round bar. 

Then cut a dumbbell contour into the pipe. It does not need to be deep - just enough so you can traverse the bar end to end without cutting in the middle. The purpose is to avoid any possibility of moving or springing the cross-slide. 

The reason for pipe instead of bar is to reduce the amount the bar droops under its own weight. But for short lengths a regular bar will work just fine. 

When you start the process of cutting the two ends and measuring the taper, take very very fine cuts to avoid deflecting the bar with tool pressure. A very very sharp hss tool works better for this because carbide likes a bit of pressure. There are carbide bits that don't, but it's just easier to sharpen a special hss bit.

There are lots of videos on the web. Just be careful to consider how your head is mounted and how to properly adjust it. They will typically be called "levelling" the lathe. So make sure you find one that actually means taking the twist out of the bed *AND THEN* adjusting the axis of the spindle to be parallel to the axis of the bed. Here is one by Joe Pie.


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## Rauce (Apr 29, 2022)

Susquatch said:


> Personally, I'm not a fan of the MT5 test bar method anyway. It depends on a perfectly machined MT5 socket in the spindle and a perfectly machined test bar.


I’ve found that MT test bars are very accurate for the cost. The MT5 test bar I just purchased for my lathe rebuild is consistent on diameter on the straight section to .0003” over 10”. Seated in the spindle taper the TIR at the far end of the bar is .0006”.


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## Susquatch (Apr 29, 2022)

Rauce said:


> I’ve found that MT test bars are very accurate for the cost. The MT5 test bar I just purchased for my lathe rebuild is consistent on diameter on the straight section to .0003” over 10”. Seated in the spindle taper the TIR at the far end of the bar is .0006”.



That's good. But even knowing that about your bar doesn't help the guy who has no idea how good the MT on his spindle is.....

For those that do, it's just fine.

But I prefer the certainty of an in chuck test bar the first time a lathe spindle is aligned.


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## trlvn (Apr 29, 2022)

opensourcefan said:


> Yes
> 
> The taper was cut in relation to the ways. If I align the back end of the cut piece it will be aligned with the ways.



I'm really confused by the above.  We believe the axis of rotation of your lathe is misaligned with the bed (horizontally) as the machine cuts tapered parts.  The amount of misalignment is 1/2 the change in diameter for a given distance from the head.  Wouldn't you have to effectively use Rollie's Dad's Method to measure the tapered part after changing the head alignment?



opensourcefan said:


> > I have completed the first round of alignments in the absence of having a longer test bar. I wasn't able to tap it into position as the relationship between the way seats on the head and the bed ways wasn't accurate. Each time I tightened up the bolts it all went to crap again. So I ended up shimming the head both vertically and laterally. It's now  .002" within 4". I can live with that untill I get my bar.
> >
> > I think this proved that it was built this way and wasn't a bump during shipping or whatever.



I thought you stated earlier that you had verified that the axis of rotation was parallel with the bed in the vertical plane?  If so, why are you having to shim vertically now?  Is it possible your shims have fixed the horizontal alignment but screwed up the vertical?

Did you take the head fully off the machine to check for burrs or chips?

Craig


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## Rauce (Apr 29, 2022)

Susquatch said:


> That's good. But even knowing that about your bar doesn't help the guy who has no idea how good the MT on his spindle is.....
> 
> For those that do, it's just fine.
> 
> But I prefer the certainty of an in chuck test bar the first time a lathe spindle is aligned.


You’ll know how good the MT in the spindle is when you put the bar in. Any runout seen on the bar will be some combination of error in the bar + error in the spindle. If say the TIR is .001” at the furthest point from from the spindle along the bar then assuming the diameter of the bar is consistent, the bar is true to the spindle bore to .0005” along the length (+/- any variation in the diameter/2) 

The certainty of a test bar like you described is great but often when aligning the headstock you don’t have the benefit of the machine in question running in order to make such a bar that’s matched to the machine/chuck etc. in question.


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## Susquatch (Apr 29, 2022)

trlvn said:


> Wouldn't you have to effectively use Rollie's Dad's Method to measure the tapered part after changing the head alignment?



Or any other equivalent method...... Rollie's dad and I had a fight over my sister once so we don't get along. I prefer regular geometry.


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## Susquatch (Apr 29, 2022)

Rauce said:


> You’ll know how good the MT in the spindle is when you put the bar in. Any runout seen on the bar will be some combination of error in the bar + error in the spindle. If say the TIR is .001” at the furthest point from from the spindle along the bar then assuming the diameter of the bar is consistent, the bar is true to the spindle bore to .0005” along the length (+/- any variation in the diameter/2)
> 
> The certainty of a test bar like you described is great but often when aligning the headstock you don’t have the benefit of the machine in question running in order to make such a bar that’s matched to the machine/chuck etc. in question.



I don't agree with that.

The whole point of making a bar in the spindle that is being aligned is to check the alignment of the spindle. A known bar is not required and need not be matched to anything.

Edit - Much as I don't like Rollie's dad, you can google it to see how it works. But the bottom line is that a rotating spindle should cut a perfect cylinder if the cutting tip is moving on a path that is parallel to the axis of the spindle. That's the whole operating principle of a lathe. If it doesn't cut a cylinder, then the two axis (spindle & bed) are not parallel. Easy peasy.


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## Rauce (Apr 29, 2022)

Susquatch said:


> I don't agree with that.
> 
> The whole point of making a bar in the spindle that is being aligned is to check the alignment of the spindle. A known bar is not required and need not be matched to anything.



What I meant by “matched” is that (unless I’m misunderstanding you) as soon as you remove your bar from the chuck it’s going to be somewhat difficult to put it back in the chuck with exactly the same alignment to the spindle. Leaving it in the chuck and the chuck on the machine while you align the headstock might be an option here but not always, which is where a cyclindrically ground MT test bar with precision that’s easily measured is better. You don’t need the machine to be operational to cut a test bar and you can take it in and out of spindle as many times as you need and it will be in alignment with the spindle within tenths every time. And in between removing it and reinstalling it you can remove the headstock to scrape or shim or whatever until you get aligned to your satisfaction.


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## opensourcefan (Apr 29, 2022)

@Susquatch 

I like the idea of not having to buy a bar specifically for this machine. The dumbbell shape seems better than dragging my indicator all the way back and forth watching it ride the surface imperfections. Maybe a 3" pipe over 15" or so would work?

I'll wait for the new chuck to arrive.


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## opensourcefan (Apr 29, 2022)

UPDATE - Electrical Quality

So during my disassembly I had to remove most of the electrical. While doing so I had two terminals fall off their wires. One connection fell out of the 3 pin connector for the rpm gauge and one on the power on off switch. I'm sure I'll discover more during round two of the alignment.


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## PeterT (Apr 29, 2022)

@opensourcefan I didn't read through your entire post, but you might find link below of interest. Specifically post #28. My contribution on this subject is somewhat repetitive to what I've typed elsewhere on this forum, some copy-pasted. I'm growing weary of headstock rotation deniers & YouTubers that regurgitate the same Google results whether it makes sense or is applicable. 

- sounds like you found the vertical bolts that secure the HS to the bed, but there may be other adjustment screws or 'alignment systems' which set the HS rotation relative to the bed. This is highly lathe dependent and what seems to be often the case, undocumented in the lathes own parts manual. If it was incorrectly set at the factory and/or has come out of alignment, then yes unfortunately leaves the task of fixing it. HS alignment has nothing to do with chucks. 

- I'm not sure why the resistance to MT-ended test bars other than the usual (expense) which of course is a personal decision. In my case I found an inexpensive one on Ebay that is very accurate for this purpose. If it helps matters, they have utility for HS alignment TS alignment & rotary table centering.

- I'm not opposed to cutting coupons to validate things, but (IMHO) its best reserved as a final / tuning / validation step when you have eliminated other, potentially larger error sources by simple measurement. Others have a different opinion & that's fine. If you visualize what is happening with either bed twist or HS is misaligned is the cutting edge is either drifting above or below the rotation axis of the coupon as it traverses. So its not quite as simple as just removing material because the cutter & material are responding differently no different than if you set your tool too low or high in normal cutting. Now I imagine this effect diminishes as you converge on correct geometry. There are many paths to arrive at the desired end result. I'm just suggesting something that seems logical & efficient to me.





__





						Lathe Headstock Alignment
					

How then would you check the alignment of the HS and then proceed to correcting twist? ie how do you tell if the misalignment is from the headstock or a twist in the bed.




					www.homemodelenginemachinist.com


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## YotaBota (Apr 29, 2022)

Hoping all works out for you and that a new chuck makes up for all the aggravation.

I know MT is supposed to be standard but if you have one company making MT stuff using metric machines and one company using inch machines is there not a chance the MT could differ enough between the two that it could be measured? That would also include the competency of the programmer and to what decimal place they programmed the machine cutting the MT.


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## DPittman (Apr 29, 2022)

opensourcefan said:


> UPDATE - Electrical Quality
> 
> So during my disassembly I had to remove most of the electrical. While doing so I had two terminals fall off their wires. One connection fell out of the 3 pin connector for the rpm gauge and one on the power on off switch. I'm sure I'll discover more during round two of the alignment.


Well I guess on the bright side of things when you get the thing up and running you will have confidence in the machine because you will have thoroughly gone through everything.


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## DPittman (Apr 29, 2022)

YotaBota said:


> YotaBota said:
> 
> 
> > I know MT is supposed to be standard but if you have one company making MT stuff using metric machines and one company using inch machines is there not a chance the MT could differ enough between the two that it could be measured?
> ...


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## opensourcefan (Apr 29, 2022)

YotaBota said:


> Hoping all works out for you and that a new chuck makes up for all the aggravation.
> 
> I know MT is supposed to be standard but if you have one company making MT stuff using metric machines and one company using inch machines is there not a chance the MT could differ enough between the two that it could be measured? That would also include the competency of the programmer and to what decimal place they programmed the machine cutting the MT.


That is one of my fears about getting a bar. The affordable ones seem to be made in India, it'll be shipped from there and I have no assurance of it arriving safely. They all seem to claim .0002" but I don't have a lot of faith in that either.

At least if I make a cut with the rotation of this lathe then I'll know it is what it is.


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## opensourcefan (Apr 29, 2022)

DPittman said:


> Well I guess on the bright side of things when you get the thing up and running you will have confidence in the machine because you will have thoroughly gone through everything.


Yep, and part of me knew that I would need to do that but I was falsely given the impression and believed that this one would be better. I fell for it.


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## DPittman (Apr 29, 2022)

opensourcefan said:


> Yep, and part of me knew that I would need to do that but I was falsely given the impression and believed that this one would be better. I fell for it.


Yup India is where my "affordable " test bar came from


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## Rauce (Apr 29, 2022)

FWIW I have three MT test bars from India MT5, MT3 and MT2 and all appear to meet specifications.


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## PeterT (Apr 29, 2022)

YotaBota said:


> I know MT is supposed to be standard but if you have one company making MT stuff using metric machines and one company using inch machines is there not a chance the MT could differ enough between the two that it could be measured? That would also include the competency of the programmer and to what decimal place they programmed the machine cutting the MT.


MT (Morse Taper) number is basically an angle when you get down to it. It came about for historical reasons & has perpetuated to current machines. Whether expressed as inch/foot, inch/inch, mm/meter, decimal degrees, Angular Deg-Min-Sec.... its the same thing & should be metric/imperial agnostic. What you might be asking is how accurately is it made which is a tolerance issue & machine/operator certainly comes into play. If there is no stated tolerance then you have to cross your fingers. If its a stated tolerance & hobbyists class & from a far away land with certain reputations & costs $50, you might also have to ask if you can believe it. And if you even have the means to even validate it. Generally speaking, centerless grinding if done properly, should be superior to anything cut off a lathe in both accuracy & finish, unless the lathe part has been lapped. 

The Ebay test bar I bought was made in India which I figured was probably throwing money out the window big time. The USA made ones were way out of the budget & these are generally not high volume items. I cant recall exactly now but I think mine said 'centerless ground within 0.0002", but no stated tolerance as to the MT angle. So now we get into relative tradeoffs of unknowns & I suspect others may have a different opinion. I felt reasonably confident that my MT spindle socket was ground sufficiently accurate and ground simultaneously as the other spindle features that dictate chuck fit-up & concentricity. My DTI said it was concentric at increments down the bore (not egg shaped). Several decent quality MT tools fit very well as evidenced by blue-ing. When the test bar arrived (in a hopelessly inadequate bubble wrap envelope but semi-padded box) I checked the socket fit again by bluing & it was exceptional. Diameter readings down the length of bar confirmed the tolerance to the best of my devices (10-ths reading micrometer). I don't have a granite surface plate / datum surface to detect bar bowing but I semi-faked it by traversing down the bar with 10-ths indicator, rotate 90-deg & repeat. Again it checked out for my intended purposes. 

With these basic quality checks /- confirmed, what is important to say is a test bar in this application is a glorified extension stick. We are using simple trigonometry to our advantage by comparing bar end position over an extended length: 12,18, 24" away (depending on which one you buy). The longer the length, the more it exaggerates axis displacement. Its as simple as that. So even if the bar diameter varies by 0.0002", its not nearly as significant as if bar is pointing in/out/up/down by say 0.005" over its length. Now we have a starting reference point. Assessing this same geometry discrepancy by cutting a coupon is do-able not quite straightforward because cantilever gripping a 24" long piece of whatever metal & cutting a slice off, we are left with a question: how much of the noted diameter difference (taper) is due to geometry issues and how much is due to cutting force variations, material deflection etc. Is 0.005" difference comprised by 0.003" geometry + 0.002" cutting forces? Or maybe its 0.004" cutting forces + 0.001" geometry. Lots of opinions, significantly less real world examples & hard data at least that I have seen. if someone has something to share, lets all have a look. The test bar in the socket provides some convenience in that you have the means to make the HS adjustments right then & there with DTI residing on the bar. 

I'm not saying cutting has no place, it certainly does because it reflects real world conditions where the lathe is doing what its intending to do. But IMO, if its a bolt on HS I see value in validating what might be overriding dominating problems with a test bar first & followup/validation cutting second. In the end we all have to try & sort out amongst the chatter what makes sense & find our own way.


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## YotaBota (Apr 29, 2022)

PeterT said:


> In the end we all have to try & sort out amongst the chatter what makes sense & find our own way.


Pun intended?lol


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## opensourcefan (Apr 29, 2022)

MT5 Test Bar ordered from India. I'll advise if I don't like and when I put it up for sale.


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## GummyMonster (Apr 30, 2022)

Just wondering, could a test bar not be easily made by someone with a lathe that's accuracy is known and repeatable?
I'm curious why you need to order one from across the globe?
Ken


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## RobinHood (Apr 30, 2022)

GummyMonster said:


> Just wondering, could a test bar not be easily made by someone with a lathe that's accuracy is known and repeatable?



The short answer is: yes.

The long one: it is not that easy, takes time and $$s to make one. Not sure what an import MT5 test bar sells for. The cost of a suitable piece of 4140 here is probably at least that amount, if not more. You have not even machined, hardened and ground it yet.

Now, if you want to make your own just for a fun project, by all means. It will take much more time/effort than most think to make an accurate test bar.


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## PeterT (Apr 30, 2022)

Looks like different (Ebay) seller names vs when I bought mine, but prices look something like this. Just enter 'MT3 test bar' or 'lathe alignment test bar'. Some sell shorties only, others various lengths. I'm reluctant to endorse so best to review the purchaser satisfaction comments & familiarize with refund policy beforehand (assuming its even offered). Looks like some now come in a wood box which is a step up from my cardboard. 

I do recall the outfit I bought from had a link showing the cylindrical grinding in action. Not that I would recognize the machine or how it was operated. Or maybe that's the factory all right & I'm dealing with a middleman... who knows. For $50 I'm not expecting nuclear aerospace equipment & I personally cannot replicate grinding like this. They might be available at other distributors like Accusize or Shars now too, I haven't checked. That might provide some added QC or bailout option.


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## Susquatch (Apr 30, 2022)

This subject comes up quite often and usually gets re-hashed to death. In an attempt to get things back on track and no offense intended to those who disagree, I think there are many ways to test (and if possible correct) the alignment of the spindle and bed of a lathe. Its a relatively doable thing for those who understand it and voodoo magic for those who don't.

Those that do understand it seem to have their preferred method. and like me, we don't like it when someone else tells us why our method sucks compared to theirs. I don't think that's usually the intention, but it seems to be what often happens.

But the bottom line is that they all work under the right conditions. The other thing about those that do understand is that we usually assume the other guys who are asking about it are misunderstanding the whole situation or the method.

So all that said, it is my opinion that this particular OP - @opensourcefan - understands the issue just fine. I really don't think I/we are helping by further debating the matter.

For those that are particularly interested in this subject, I previously created a special thread on this forum for it. I have not had a chance to work on that project for quite a while now (main focus has been on getting my mill working) but I do hope to get to it soon. Since it's MY THREAD, it is about making a special dumbbell bar test bar with re-usable collars and optimized constraints and goals. It isn't about using Morse Tapers. Nonetheless I welcome the discussion about how much better an MT might be. In fact, ideally I'd even like to reach a consensus. Therefore, I invite anyone who has thoughts, beliefs, and preferences to join me there to help me beat the subject to death.

Thread 'Lathe Alignment' https://canadianhobbymetalworkers.com/threads/lathe-alignment.4723/





GummyMonster said:


> Just wondering, could a test bar not be easily made by someone with a lathe that's accuracy is known and repeatable?
> I'm curious why you need to order one from across the globe?
> Ken



See the above thread where I am attempting to do just that. The project is on hold right now while I finish my mill work. My concept is a fair bit more complex than just making a simple dumbbell primarily to make it re-usable but also to improve the accuracy.


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## David_R8 (May 1, 2022)

opensourcefan said:


> MT5 Test Bar ordered from India. I'll advise if I don't like and when I put it up for sale.


Where did you order from?


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## opensourcefan (May 1, 2022)

David_R8 said:


> Where did you order from?


Sorry for the late reply.

Ordered from eBay. There's a pile of sellers, all from India, probably all the same outfit.


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## opensourcefan (May 12, 2022)

opensourcefan said:


> MT5 Test Bar ordered from India. I'll advise if I don't like and when I put it up for sale.


UPDATE

Seller flaked, never shipped and didn't respond to any messages. Ebay cancelled it for me without issue. I can't seem to find a seller from India that doesn't have the same negative feedback.


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## StevSmar (May 12, 2022)

Sorry that you’ve had such a negative response to your purchase.

I do like the colour, probably because it reminds me of the old kitchen cabinets at the cottage.

When I was looking for a lathe I stopped off at a vendor who appeared to stock only Chinese lathes at an aggressive price point. I left with the feeling that whatever I purchased from them I’d be dissapointed with. Knowing what I know now I think I’d be less reluctant, as long as I saw the actual lathe in person.

I did end up purchasing a Precision Mathew’s lathe that more than met my biases, however it was significantly more expensive than where I started out…


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## StevSmar (May 12, 2022)

opensourcefan said:


> I can't seem to find a seller from India that doesn't have the same negative feedback.


I ordered a MT5 test bar from Auzaar and had no issues.
I can’t comment on the accuracy as I don’t have the tools to confirm. It appears well made.
https://www.ebay.ca/itm/324612738341


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## VicHobbyGuy (May 12, 2022)

opensourcefan said:


> I can't seem to find a seller from India that doesn't have the same negative feedback.


I've bought as few different things from Indian eBay seller sputniktools - MT test bar, mini lathe milling attachment - and gotten good service. Very fast delivery (week to 10 days) by UPS which means that GST + $10 handling fee was payable, but that was OK with me. The test bar I bought was MT3, obviously the MT5 is bigger and more expensive: https://www.ebay.com/itm/363622460904?hash=item54a9966de8:g:o5oAAOSwIuNhkg7B
I've also purchased (adjustable reamers, HSS parting tool blanks) from eBay Indian seller daily_tools, and wasn't so impressed with the quality, though the items did arrive.


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## Rauce (May 12, 2022)

I got my MT5 test bar from Atoz Tools just a few weeks ago, they sell on eBay and amazon but I got it on eBay. It checks out well accuracy wise. Only real disappointment was that the wood box was not very good and went straight in the trash.


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## VicHobbyGuy (May 12, 2022)

Rauce said:


> Only real disappointment was that the wood box was not very good and went straight in the trash.


Wood box? My MT3 bar came in a finely finished Indian cardboard box with blue paper glued on the outside.


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## opensourcefan (May 12, 2022)

Good to know that I may have success, I'll try one of your guy's suggestions.


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## StevSmar (May 13, 2022)

Rauce said:


> Only real disappointment was that the wood box was not very good and went straight in the trash.


My wooden box was as shown in the photographs. It was shipped a separate, identical cardboard box. Which I suspect was because the wooden box would have been destroyed by the weight of the test bar during shipping.




I was happy with the purchase, which then gave me the confidence to purchase a knurling tool from the vendor.


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## Susquatch (May 13, 2022)

StevSmar said:


> My wooden box was as shown in the photographs. It was shipped a separate, identical cardboard box. Which I suspect was because the wooden box would have been destroyed by the weight of the test bar during shipping.
> View attachment 23839
> I was happy with the purchase, which then gave me the confidence to purchase a knurling tool from the vendor.



Hey @StevSmar, Who is the vendor and what is the knurling tool you bought?


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## StevSmar (May 13, 2022)

Susquatch said:


> …Who is the vendor and what is the knurling tool you bought?


This was the test bar:
https://www.ebay.ca/itm/324612738341
And the knurling tool:
https://www.ebay.ca/itm/325003632451
The knurling tool was about 1/5th(?) of the price of a US made one and it shows in the quality. I’m happy with it though.


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## Susquatch (May 13, 2022)

StevSmar said:


> This was the test bar:
> https://www.ebay.ca/itm/324612738341
> And the knurling tool:
> https://www.ebay.ca/itm/325003632451
> The knurling tool was about 1/5th(?) of the price of a US made one and it shows in the quality. I’m happy with it though.



Thank you!

I want to get an offshore test bar to compare with my standard methods. I dunno about the knurling tool......


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## StevSmar (May 15, 2022)

Susquatch said:


> I want to get an offshore test bar to compare with my standard methods...


Based on my one try at using a test bar, I currently think test bars get you into the ballpark and after that turning two collars is really the true test.

I had about 0.002” runout on the end of my 15” test bar and unfortunately I don’t have enough tools to tell whether the runout was due to the lathes spindle bore or the test bar.

I’m still undecided if it was worth getting one.


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## 140mower (May 15, 2022)

StevSmar said:


> Based on my one try at using a test bar, I currently think test bars get you into the ballpark and after that turning two collars is really the true test.
> 
> I had about 0.002” runout on the end of my 15” test bar and unfortunately I don’t have enough tools to tell whether the runout was due to the lathes spindle bore or the test bar.
> 
> I’m still undecided if it was worth getting one.


Someone smarter than me is likely to add their two bits, but for most of us, .002" at 15" from the headstock sounds pretty good on a hobby lathe to me..... Now if it was Darren's 10ee or Rauce's Hendey, I might think otherwise......


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## Rauce (May 15, 2022)

140mower said:


> Someone smarter than me is likely to add their two bits, but for most of us, .002" at 15" from the headstock sounds pretty good on a hobby lathe to me..... Now if it was Darren's 10ee or Rauce's Hendey, I might think otherwise......


I clocked .0006” on my test bar 12” out. Which would be some combination of error in the bar and magnified runout in the MT5 taper in the headstock.

Keep in mind that for the purpose of checking the carriage against the test bar the amount that the test bar would be off is half the TIR (assuming consistent OD). By turning the spindle and averaging readings as Mcgyver has detailed you can eliminate the runout from the equation.

I don’t think checking the bar takes much by way of equipment. A mic will check the OD along the length. You can check for bow by measuring runout between centres on your lathe or across a pair of v blocks.


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## Susquatch (May 16, 2022)

I appologize to everyone. I should have finished my experiments on this subject ages ago. 

A factor that has not been mentioned is the effect of gravity on the test bar. It is easy to do a quick calculation but it will not be correct enough to use for this purpose because the material bending strength varies. I believe a measurement is better. 

Bending due to gravity is the reason I decided to use a piece of pipe. Pipe has much higher resistance to bending from its own weight than bar steel could ever have. 

Length magnifies the measurement but also adds more gravity error due to bending. I intend to measure this to determine the optimum length and pipe specifications. 

Without having actually done this yet, I'll wager a bet that at 8" the gravity effect is negligible and at 12" it becomes important. I think that pipe might allow one to go to 16" or even 24.

More importantly, by actually measuring the bending, one can take it into account mathematically. 

Again, without actually having done it, I expect that measuring it is as simple as hanging a weight at the halfway point that is equal to the unsupported weight of the bar and measuring the static deflection.


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## Degen (May 16, 2022)

Susquatch said:


> I appologize to everyone. I should have finished my experiments on this subject ages ago.
> 
> A factor that has not been mentioned is the effect of gravity on the test bar. It is easy to do a quick calculation but it will not be correct enough to use for this purpose because the material bending strength varies. I believe a measurement is better.
> 
> ...


As this may look like an issue its not as it will have the same effect if the bar is measured from the bottom (or top) and the effect will remain constant. Now if the defection changes.....there is a misalignment.


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## Susquatch (May 16, 2022)

Degen said:


> As this may look like an issue its not as it will have the same effect if the bar is measured from the bottom (or top) and the effect will remain constant. Now if the defection changes.....there is a misalignment.



I don't think that's true. 

For the sake of simplifying the discussion, let's suppose we are talking about vertical misalignment only with no side to side misalignment. 

A measurement at the head is is the reference. If you then measure at the far end of the bar, any bending of the bar due to gravity will look like vertical misalignment (pointing down) even if none is actually there. I believe that is why most alignment bars are relatively short.


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## Degen (May 17, 2022)

Susquatch said:


> I don't think that's true.
> 
> For the sake of simplifying the discussion, let's suppose we are talking about vertical misalignment only with no side to side misalignment.
> 
> A measurement at the head is is the reference. If you then measure at the far end of the bar, any bending of the bar due to gravity will look like vertical misalignment (pointing down) even if none is actually there. I believe that is why most alignment bars are relatively short.


In that case you are in real trouble as your bed of the lathe for it would have even more sag in the middle as it is supported at the ends on pivots.

Seriously in terms of deflection, the alignment bar does deflect a small amount, which you can calculate before hand (structural steel handbook has all the formulas, brings back memories in steel building design).  Now if the deflection is say 0.000001 per ft (calculated) you consider that as zero. If its less then you head is pointed up, if its more then down.

I would see more influence in errors in a tool in cutting as it applies considerably more forces than gravity in substantially more directions at same time.

I would also add unless you stat looking into temperature if you are getting into this level of precision you are wasting your time as it will effect you readings even more given cast, steel, and a list of other materials used in the lathe.

I see this as chasing rainbows in terms of reading too much into measurements to achieve accuracy.   Don't over complicate things.


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## Susquatch (May 17, 2022)

Degen said:


> In that case you are in real trouble as your bed of the lathe for it would have even more sag in the middle as it is supported at the ends on pivots.
> 
> Seriously in terms of deflection, the alignment bar does deflect a small amount, which you can calculate before hand (structural steel handbook has all the formulas, brings back memories in steel building design).  Now if the deflection is say 0.000001 per ft (calculated) you consider that as zero. If its less then you head is pointed up, if its more then down.
> 
> ...



I think one of us has flawed math.

But, besides the fact that I am prejudiced to prefer my own version, I'll also pick my version simply because you indicated the deflection is linearly proportional to length. ("Now if the deflection is say 0.000001 per ft (calculated)... ").

That is clearly not correct. The deflection is not linear with length.

My math calculates 3 tenths for a 12" bar of average strength (30,000ksi) and a diameter of 1.125" (chosen only for convenience to have a cross sectional area of 1 sq-in to simplify the calc).

For a 16" bar, the calculated deflection is about 1 thou. And for a 2ft bar it is 5 thou.

This compares favorably with the results determined using on-line calculators and other references for Lathe alignment bar deflection I looked at in the past. It is also specifically mentioned in numerous places as the reason for using a shorter bar.

This is also the reason that I am exploring the use of a pipe. A pipe (cylinder) has a much better second moment of area to weight ratio.

Lastly, your comments about how these numbers affect the use of the lathe and alignment of the head suggest maybe we are not on the same page on that subject either.

As others have pointed out, some lathe designs cannot be easily adjusted. Some can be adjusted with great difficulty, and some are just difficult. I've never heard of one that was easy. In my own case, it is just difficult. Mine is done using the six base feet which are used to change the bed twist as well as the head alignment.

For those who have non-adjustable heads, the only purpose of testing the alignment is to know what it is. For the rest of us, it's good to be able to get it as close as practical.

For obvious reasons, a long bar makes it easier to detect small angular differences. But the deflection caused by its own weight works against that.

Your comments about simply taking the deflection into account reflect my own thoughts. If it's negligeable (as it is for short lengths) then as you say, I don't need to worry about it. But since I'd prefer to use a longer bar to magnify the measurement, it probably won't be negligeable. In that case, it must be accounted for.

I don't think accounting for it is as simple as a calculation. Yes, the calculation can get you close, but a measurement can get you bang on. Once you know what it is, I agree with your comments that you can simply adjust your alignment measurements accordingly. Hence my reason for wanting to know what it is...... LOL!

I plan to do some actual measurements in the near future. I'll certainly find out then whose numbers are correct. Those measured numbers will have a profound effect on the final design of my proposed test bar with replaceable collars.

In the meantime, I have ordered an MT5 test bar to use for comparison purposes. And then we will see what we will see about all of this.

I also agree with your comments about the affect of tool pressure. But it's also unknown. So I want to measure it and develop a procedure to accomodate it.

As long as it is stabilized and constant, I don't think temperature is that important for this application. My shop is temperature stable and I always warm my equipment up before any precision work. But that is just an opinion. I have no information or data to suggest otherwise. Nonetheless I am fairly confident that it is much less important than quantifying the weight deflection issue.


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## Degen (May 17, 2022)

The number I used was just for example, not an actual number.

As to how beam deflect as forces are applied depends greatly on how the they are mounted, in some case become very complex in mathematical solution.  As you suggested the use of 6 point leveling system does give you control but it also adds variables that are very undersireable. (BTW my new lathe has this too ). 

As to temperature it does have a bigger effect than you suspect, so much so it was part of an engineering lesson (lab).

Regardless of the deflection if you know what it is, it allows you to confirm whether or not the head is aligned or not.   If the calculated value at 2' is 5 thou, measure close and measure at the end, if it 5 thou, you good, if not start tweaking.


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## Susquatch (May 17, 2022)

Degen said:


> As to temperature it does have a bigger effect than you suspect, so much so it was part of an engineering lesson (lab).



Oh, I think you totally underestimate what I know about such things..... And of course, I probably overestimate it. LOL! 

Frankly, I think you and I are just worried about opposite ends of extremes. In my opinion, temp effect is an easy calculation that is insignificant for what we are talking about here. I see this as chasing rainbows in terms of reading too much into it. Don't over complicate things. LOL! (Sorry, Devil made me say that - just using the same words you used earlier for the humour effect!) 

Anyway, in this case the radial expansion is well below my ability to measure it and I don't believe that longitudinal expansion matters in this application. In case you are wondering, the average coefficient of thermal expansion for steel is just 0.00000645in/in/deg F. 

Rather than chasing MY tail, which is not something I'd be wanting to do if I were you, I'd suggest you wait until I complete my assessment of this whole subject in designing my new collared system. I'll have actual measurements and comparison testing of other methods at that time and I will make all of it available for peer review on my thread for that. I'd like to believe that I will be totally open to any and all criticism or suggestions for improvements that anyone cares to provide at that time.


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## Degen (May 17, 2022)

@Susquatch since we've spoke by phone, I think we speak and see the same things so a good educational banter helps others.

I think both of us have a little OCD.


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## Susquatch (May 17, 2022)

Degen said:


> @Susquatch since we've spoke by phone, I think we speak and see the same things so a good educational banter helps others.
> 
> I think both of us have a little OCD.



And here we go again at opposite sides of two extremes. I believe you have totally underestimated me again. I do NOT have a little OCD.

I have at least two orders of magnitude higher OCD than a little. 

And that is actually significantly reduced in intensity ever since I passed 65 right in tune with my vision, my hearing, my coordination, and my memory.


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## Degen (May 17, 2022)

Susquatch said:


> And here we go again at opposite sides of two extremes. I believe you have totally underestimated me again. I do NOT have a little OCD.
> 
> I have at least two orders of magnitude higher OCD than a little.
> 
> And that is actually significantly reduced in intensity ever since I passed 65 right in tune with my vision, my hearing, my coordination, and my memory.


I've learned to understate things, helps keeping people off guard. 

BTW me too.


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## StevSmar (May 22, 2022)

Susquatch said:


> …For a 16" bar, the calculated deflection is about 1 thou. And for a 2ft bar it is 5 thou...


Does it matter whether the test bar sags? Isn’t the primary reason for using a test bar for adjusting twist? The measurement on the vertical face of the test bar is not going to see much of a change in radius from sag.
(Edit: I did a sketch in Fusion 360 to see what 0.001” sag will do for a reading of the vertical face. It's smaller than what Fusion can display...)
(I first did the sketch with a 0.01 sag to make sure I had the sketch constraints correct, then I changed the 0.01 dimension to 0.001)







Susquatch said:


> …This is also the reason that I am exploring the use of a pipe. A pipe (cylinder) has a much better second moment of area to weight ratio…


What about a carbon fibre pipe test bar? That would look very nice too!


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## whydontu (May 22, 2022)

Using my favourite design tool for piping - Engineering Power Tools Plus Edition (check it out)






						Engineering Power Tools – Powerful Productivity Software for Professional Engineers
					






					pwr-tools.com
				




I picked 1-1/4" Sch40 as a largest size that would fit in most large hobby lathes. I also solved for 1/2" that would likely fit in a 7/8" collet.

15" length of 1-1/4" Sch40 steel pipe 1.660 O.D. at 2.268 lbs/ft, simple cantilever, supported at one end only, uniform weight distribution, solves at 0.0002" deflection at the free end, 90.633 psi stress. 21.26 in-lbs torque at the chuck end.

1/2" Sch40 deflects 0.840" O.D. 0.0009" in the same conditions.

All mostly irrelevant, because the chances of getting a straight piece of pipe is about the same as me being elected Pope.


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## StevSmar (May 22, 2022)

whydontu said:


> All mostly irrelevant, because the chances of getting a straight piece of pipe is about the same as me being elected Pope.


Don’t worry, when I’m the ruler of the world I’ll make you pope. And I’ll give orders to initiate a research program to solve this discussion.


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## whydontu (May 22, 2022)

Susquatch said:


> Oh, I think you totally underestimate what I know about such things..... And of course, I probably overestimate it. LOL!
> 
> Frankly, I think you and I are just worried about opposite ends of extremes. In my opinion, temp effect is an easy calculation that is insignificant for what we are talking about here. I see this as chasing rainbows in terms of reading too much into it. Don't over complicate things. LOL! (Sorry, Devil made me say that - just using the same words you used earlier for the humour effect!)
> 
> ...


Wow, you’re even more anal about numbers than I am. I usually did my thermal expansion calcs using 0.00006”/”/*F, but I was typically only doing steam piping deflection and the temperature range was only maybe 500* F from cold to hot.


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## chip4charlie (May 22, 2022)

Ordered a MT3 test bar from India off Ebay. It was here in 6 days.


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## Susquatch (May 22, 2022)

StevSmar said:


> Does it matter whether the test bar sags? Isn’t the primary reason for using a test bar for adjusting twist? The measurement on the vertical face of the test bar is not going to see much of a change in radius from sag.
> (Edit: I did a sketch in Fusion 360 to see what 0.001” sag will do for a reading of the vertical face. It's smaller than what Fusion can display...)
> (I first did the sketch with a 0.01 sag to make sure I had the sketch constraints correct, then I changed the 0.01 dimension to 0.001)
> 
> ...



I believe the sag matters. Twist is measured and corrected before head parallelism is evaluated and corrected (if possible).

I think it's best to look at this whole deal (no matter what words you use to describe it) as: 
1. Bed alignment (twist, bending, etc). Sometimes misleadingly called levelling. 
2. Tailstock alignment (usually associated with cutting tapers)
3. Head alignment with the bed. Axis of rotation parallel to the axis of the bed. Not pointing up/down/right/left. 

Not all of these are adjustable on all lathes. 

My focus in this discussion is strictly #3.

Carbon Fiber - YES! I bet carbon fiber would be awesome for this. It is both stiff and light. But you still need machinable collars to do the actual testing. And I'm not sure where to get (or make) the appropriate carbon fiber bars.


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## Susquatch (May 22, 2022)

whydontu said:


> Wow, you’re even more anal about numbers than I am. I usually did my thermal expansion calcs using 0.00006”/”/*F, but I was typically only doing steam piping deflection and the temperature range was only maybe 500* F from cold to hot.



Yes, I am anal with numbers. But only for theoretical purposes. For actual applications, I prefer testing to validate the theory (which often means pitching the theory in the trash.... LOL!)


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## Susquatch (May 22, 2022)

whydontu said:


> All mostly irrelevant, because the chances of getting a straight piece of pipe is about the same as me being elected Pope.



Get ready for papal duty... 

Straighness of the pipe doesn't matter. That's what the collars are for. 

Two collars are attached to the pipe. In my original thinking, they are aluminium. One is attached just in front of the chuck jaws, the other at the far free end. Extremely shallow very low pressure cuts are made on both collars with a VERY sharp tip. The idea is to avoid deflecting the bar in the process of cutting it. It's not really possible but can be minimized.


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## Susquatch (May 22, 2022)

StevSmar said:


> And I’ll give orders to initiate a research program to solve this discussion.



Woah Woah Woah! Not so fast Oh Great Ruler of the World!  Thy worthy and respected command is already being made so!

Your unworthy servant of big and hairy proportions is already doing the research to resolve this matter. He doesn't need to be taking any orders from Pope @whydontu.

Of course, everyone is welcome to join on (pile on) and provide peer review (aka feedback criticism support & debate) over on that thread.

Work on the research is temporarily on hold in favour of higher priority tasks.

Edit - Here is a link to that thread 'Lathe Alignment' https://canadianhobbymetalworkers.com/threads/lathe-alignment.4723/


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## Susquatch (May 22, 2022)

whydontu said:


> Using my favourite design tool for piping - Engineering Power Tools Plus Edition (check it out)
> 
> 
> 
> ...



I think you understand what I am after here. My choice of a piece of black pipe was driven mostly by availability and low cost, but also by suitability for the task. 

Could you take a bit of time using your tool to assist me in selecting a better candidate for this application? Ideally the lowest deflection due to weight and tip force possible while still fitting reasonably well in the chuck jaws. I agree that 1.25" diameter is about right.


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## whydontu (May 22, 2022)

1" Sch10 steel pipe - 1.315" nominal O.D., 0.109" wall, 1.097" I.D.. Find a fire sprinkler contractor, common size for press fit branch runs. 0.0003" deflection over 15" span.

1" Sch40 0.133" wall, 1.049" I.D., deflection will be bit more but EPT only solves to tenths. Pipe is a bit heavier.

Pipe dimensions tend to be pretty close on O.D., but usually a little heavier than nominal on wall thickness. No pipe manufacturer has ever been sued for making the pipe a touch thicker than required by spec.

Collar suggestion - turn down the end of the 1" pipe to 1.250". Leaves 0.076" wall thickness on Sch10, 0.100" wall on Sch40. Cut a shallow taper from 1.250" to 1.315" over 1" span. Cut a matching taper in your sacrificial collars. At <4 degree taper you're well into the range for a wringing taper. Lightly press collars onto bar. Taper combined with Loctite if you're a belts and suspenders type of guy.

Sketch attached. I drew the pipe as 1.3" O.D., just because I just did a snap-to-grid at 0.025", and even if you did a 0.007" cleanup cut on the pipe O.D. you'd still have lots of meat.


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## whydontu (May 22, 2022)

BTW, this forum is stretching my brain. I've been using a CAD program called CADstd (http://www.cadstd.com/history/index.html) since 1987. I've forced every employer to buy me a copy. And I've bought my own copies every time my PCs switched to new OS versions. Maybe I‘m their best return customer.

And today, realizing I wanted to do a screen capture with a white background, I had to read the manual and learn I could switch to a white background. I've been using CADstd with a black background for 30+ years because I started when it was DOS and that's where my brain stuck. Sigh.


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## Susquatch (May 22, 2022)

whydontu said:


> 1" Sch10 steel pipe - 1.315" nominal O.D., 0.109" wall, 1.097" I.D.. Find a fire sprinkler contractor, common size for press fit branch runs. 0.0003" deflection over 15" span.
> 
> 1" Sch40 0.133" wall, 1.049" I.D., deflection will be bit more but EPT only solves to tenths. Pipe is a bit heavier.
> 
> ...



Excellent stuff. 

My career brain is wired to design for optimum and reduce cost through volume. 

My farm brain is wired to use the cheapest thing I can find out in the yard and force it to work. 

I'll use that info (and give you credit) including the taper fit, as soon as the project matures...... unless it dies of errors, bad assumptions, a better idea, or priority rot. Lots of ground and experiments between here and there. 

How expensive is fire pipe compared to regular pipe?

I'm thinking about maybe modifying your taper idea a wee bit. I'd prefer not to thin out or weaken the chuck end to accomodate a taper. So I'm thinking about a double collar at that end. One that is solidly attached to the pipe and then another collar on top of that one that is attached with a taper for replaceability. 

Thank you!


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## PeterT (May 22, 2022)

I'm not sure I fully understand where you guys are going with this deflection thing. In post #94 @Susquatch volunteered some deflection numbers just as an example. Lets take the longest one just for discussion purposes. S=30,000 ksi, OD=1.125", L = 24". Resultant deflection = 0.005".

Now refer to crude sketch below, side view of bar, dramatically exaggerated. If this was a precision test bar, the sag would be represented by the lower curved lines only. The black line represents a DTI trace traversing down the length. If we zeroed it on on the 9:00 quadrant on left side, the chuck side, the DTI it would end up slightly higher on the circle on the right side. So one could say the needle is deflecting  as though the HS was pointing towards the rear of lathe looking down from the top potentially giving us a false signal in an otherwise perfect geometry lathe. This detail is real but typically glossed over as negligible for weekend warriors. Most test bars are shorter, say 12" so will deflect less. They might may be made from higher modulus materials & deflect less on that basis, but who knows. Cantilever deflection is non-linear, most of it occurs exponentially(?) out towards the free end.

But the aforementioned is a static setup. The bar end is drooping downward in the vertical plane under its own weight at 1G. When you guys are talking about making a cutting test bar, that is a dynamic condition. The bar is now spinning at lathe RPM. Maybe I am off base but what I visualize happening is the outboard material which is off axis (arbitrary orange element) will now see increased dynamic deflection because it sees much higher G-at some distance which is increasing outboard. Maybe a loose term is 'whip'. Visualize spinning a long wire in a drill. So the view on right is showing the deflection positions that we will now be cutting through. Now things get complicated. How much are we shaving off due to this dynamic deflection? How much are we influencing the deflection by pushing the material back towards center near the outboard right end (but different than the left supported end)? We desire a long length so that the left vs right diameter difference exaggerates the axis misalignment, but now we also have these new spinning & cutting conditions to contend with.


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## Susquatch (May 22, 2022)

PeterT said:


> I'm not sure I fully understand where you guys are going with this deflection thing. In post #94 @Susquatch volunteered some deflection numbers just as an example. Lets take the longest one just for discussion purposes. S=30,000 ksi, OD=1.125", L = 24". Resultant deflection = 0.005".
> 
> Now refer to crude sketch below, side view of bar, dramatically exaggerated. If this was a precision test bar, the sag would be represented by the lower curved lines only. The black line represents a DTI trace traversing down the length. If we zeroed it on on the 9:00 quadrant on left side, the chuck side, the DTI it would end up slightly higher on the circle on the right side. So one could say the needle is deflecting  as though the HS was pointing towards the rear of lathe looking down from the top potentially giving us a false signal in an otherwise perfect geometry lathe. This detail is real but typically glossed over as negligible for weekend warriors. Most test bars are shorter, say 12" so will deflect less. They might may be made from higher modulus materials & deflect less on that basis, but who knows. Cantilever deflection is non-linear, most of it occurs exponentially(?) out towards the free end.
> 
> ...



I love how your mind works. And I like that you are thinking about such things. It helps to have someone asking those kinds of tough questions. 

I had considered this earlier and after a lot of noodling, I put it on the back burner as not likely. The simplest reason I can give is that I don't think the dynamic situation is different from the static one in any meaningful way. In other words, the bar droops constantly due to gravity as it turns. 

The bar has very high bending resistance which also means it has a very high natural frequency. I'd expect that natural frequency to be much higher than the low speed at which it would be turning during cutting. 

That said, I'm not positive of that. So it's yet another calculation and experiment to do. 

To be a bit clearer on my thinking, imagine a finite element analysis vs time. The bar can be moved a bit at a time during cutting. Let's just arbitrarily say that it's 15 degrees for each iteration for discussion purposes. In a real simulation we would choose a much smaller iteration interval. For each iteration we would calculate the time for the bar to droop, twist, vibrate, and otherwise move according to the force of gravity, and cutting tool forces.

In my mind, the high natural frequency of all those movements would be totally dominated by the relatively low frequency of rotation. 

But you know what they say about assumptions. Therefore, I do plan to do the calculations and then do the measurements needed to validate them. 

Keep thinking Peter. It is very much appreciated.


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## StevSmar (May 27, 2022)

PeterT said:


> Now refer to crude sketch below, side view of bar, dramatically exaggerated. If this was a precision test bar, the sag would be represented by the lower curved lines only...


That was the point of my sketch, except I didn’t present it as clearly as you have.


PeterT said:


> the DTI it would end up slightly higher on the circle on the right side. So one could say the needle is deflecting  as though the HS was pointing towards the rear of lathe looking down from the top potentially giving us a false signal in an otherwise perfect geometry lathe….
> 
> View attachment 24053


My sketch suggested for a 1” test bar that has deflected 0.001”, the change in DTI reading was something like 0.000001” (too small for Fusion360 to give an actual dimension)


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## Susquatch (May 27, 2022)

StevSmar said:


> That was the point of my sketch, except I didn’t present it as clearly as you have.
> 
> My sketch suggested for a 1” test bar that has deflected 0.001”, the change in DTI reading was something like 0.000001” (too small for Fusion360 to give an actual dimension)



I had only addressed @PeterT's concern about dynamic bending. But your note suggests that perhaps you guys are also talking about something else. Or perhaps I misunderstood the dynamic bending discussion too. 

Sometimes the English language sucks. On reflection, I am not at all sure that I understand what either of you are talking about when you say that a 1 thou deflection results in a 0.000001 dti reading. I suspect you are thinking that the measurement of the test bar is taken on its side where a typical tool cut is made. And the very tiny measurement you refer to is the change in the dti reading that results from a slightly higher position on the radius of the shaft caused by its droop. (that was a mouthful) If so, that isn't the idea at all. 

Setting dynamic deflections aside for now, it might help if I explain a little more about what I believe we are trying to do here. 

Ideally, we want the axis of our spindle to be parallel to the axis of the ways. However, this isn't always the case. The axis of the spindle could be pointing down or it could be pointing up (let's call both of those nod) and it could also be pointing forward or rear ward (let's call that wag). 

A rigid and solidly mounted cutting tool held in a tool holder on the cross-slide will always slide along the ways on a path that is parallel to the axis of the ways. This is a fundamental aspect of the way that a lathe works. 

If the lathe spindle axis wags inward toward the operator. The lathe will end up cutting a taper that is smaller at the far end of a bar than it is at the headstock. If it is pointing away from the operator, the far end will be fatter. Because the cutting tool is located at the vertical center of the spindles axis of rotation, the angle of the resulting taper will be proportional to the wag angle of the spindle itself. This angle can be calculated by measuring the taper. The taper measurement is taken with a Micrometer not a DTI. 

On the other hand, a cutting tool that travels the length of a test bar that points up or down does not cut as big a taper. That's because the cutting tool moves up or down the radial surface of the test bar as it traverses left or right. The result is a MUCH smaller taper. Perhaps this is the 0.000001 measurement you guys referred to. And of course, you are correct - this effect is relatively insignificant. Not only that, but it's insignificance IS IMPORTANT. Because the taper caused by any up or down nod is insignificant, the test bar will be more or less cylindrical. And because it is cylindrical, the nod can be measured. Not by measuring this insignificant taper, but rather by directly running a DTI (NOT a Micrometer) from left to right along the TOP of the test bar. A spindle that points up will result in a higher measurement at the end of the test bar, and one that points down will result in a lower measurement. 

Because nod is measured on the top of the bar, any deflection of the bar due to its own weight can interfere with a precise measurement. However, if the deflection is known, it can simply be subtracted from the nod measurement. 

Of course, there are many other ways to do this measurement and other equipment that can be used. But fundamentally, nod is measured on the top of the bar and wag is measured on the side. 

Nod and wag are two separate measurements. However, any taper caused by wag must be subtracted from or added to the nod measurement. 

Fans of the MT test bar will no doubt be quick to point out that the test bar does not require measuring tapers. Instead both nod and wag are measured directly with DTIs - at the top for Nod, and on the side for Wag. 

At the risk of re-opening an old debate, I believe the mt5 test bar method is much easier to do but that any concentrity error in the bar or MT5 socket, or any dirt in the MT5 connection will result in errors that need to identified and cancelled out. 

On the other hand, cutting a test bar requires a very sharp cutting tool, and a complicated  taper measurement. 

Both will work just fine as long as you know and understand their limitations. 

I hope that helps.


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## PeterT (May 27, 2022)

I didn't have access to my CAD tools until tonight but sketch corroborates @StevSmar example
1.125" OD bar drooping 0.005" at the end equates to a very teeny indicator delta reading (0.0000222"). Assuming I had a indicator that could measure that.


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## Susquatch (May 28, 2022)

PeterT said:


> I didn't have access to my CAD tools until tonight but sketch corroborates @StevSmar example
> 1.125" OD bar drooping 0.005" at the end equates to a very teeny indicator delta reading (0.0000222"). Assuming I had a indicator that could measure that.



Gezz Peter, I thought you understood. Now I'm not so sure. I agree with your analysis of the impact of a 5 thou droop on a reading *at the side of the bar*.

But, *when measuring spindle nod*, you don't measure at the side of the bar, *you measure along the top*!

At the top of the bar, 5 thou droop is 5 thou! This droop due to gravity must be substrated from whatever the measured nod is.


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## PeterT (May 28, 2022)

@Susquatch I'll try to explain. The CAD measurement in post 117 was just a convenient method to quantify how much needle deflection would be seen by the indicator ball riding up or down the OD of a cylinder  (round section) test bar BY WHATEVER MEANS resulting in the bar not being perfectly aligned to indicator travel. Yes if I wanted to verify the beam droop under gravity calculation (0.005" over 24" for example), I would put the indicator ball at 12:00 on HS side, traverse down the bar to the end & observe reading. But not so fast, the only way this works is if the ball ends up in the exact same 12:00 position at the bar end. If the HS was pointing slightly in or out then the ball would land towards 1:00 or 11:00. So the reading would be influenced by the circular shape, not entirely droop deflection. By how much? That's what the CAD sketch quantifies. Now If I used a rectangular section test bar, the DTI ball would occur on the same plane & this effect would not be an issue.

Anyways all post 117 says is: lets just temporarily accept that a circular section bar droops 0.005" under gravity. How much influence would my indicator see DUE TO THIS DROOP EFFECT ALONE by traversing the bar along the bar side while I am trying to ascertain HS yaw misalignment, which is still the main objective. Answer 0.0000222" = negligible. So my DTI reads 0.003" of deflection, then 99% of this reading is attributable to HS rotation, less than 1% is due to droop. IOW in a static test we don't have to worry about droop effect even to this extent.

The reason this was of interest to me is more of a generalization: the same indicator ball riding up or down the circular section effect could potentially influences other modes of measurements. For example if you have a badly worn saddle, the indicator goes along for the ride since its mounted to the saddle. So as its traversing along a cylinder test bar the ball is riding high or riding low relative to initial bar center. Exact same math. Make more sense now? I've seen people discuss bed wear effect, but have not seen much reference quantifying it relative to a cylindrical datum surface.


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## Susquatch (May 28, 2022)

PeterT said:


> @Susquatch I'll try to explain. The CAD measurement in post 117 was just a convenient method to quantify how much needle deflection would be seen by the indicator ball riding up or down the OD of a cylinder  (round section) test bar BY WHATEVER MEANS resulting in the bar not being perfectly aligned to indicator travel. Yes if I wanted to verify the beam droop under gravity calculation (0.005" over 24" for example), I would put the indicator ball at 12:00 on HS side, traverse down the bar to the end & observe reading. But not so fast, the only way this works is if the ball ends up in the exact same 12:00 position at the bar end. If the HS was pointing slightly in or out then the ball would land towards 1:00 or 11:00. So the reading would be influenced by the circular shape, not entirely droop deflection. By how much? That's what the CAD sketch quantifies. Now If I used a rectangular section test bar, the DTI ball would occur on the same plane & this effect would not be an issue.
> 
> Anyways all post 117 says is: lets just temporarily accept that a circular section bar droops 0.005" under gravity. How much influence would my indicator see DUE TO THIS DROOP EFFECT ALONE by traversing the bar along the bar side while I am trying to ascertain HS yaw misalignment, which is still the main objective. Answer 0.0000222" = negligible. So my DTI reads 0.003" of deflection, then 99% of this reading is attributable to HS rotation, less than 1% is due to droop. IOW in a static test we don't have to worry about droop effect even to this extent.
> 
> The reason this was of interest to me is more of a generalization: the same indicator ball riding up or down the circular section effect could potentially influences other modes of measurements. For example if you have a badly worn saddle, the indicator goes along for the ride since its mounted to the saddle. So as its traversing along a cylinder test bar the ball is riding high or riding low relative to initial bar center. Exact same math. Make more sense now? I've seen people discuss bed wear effect, but have not seen much reference quantifying it relative to a cylindrical datum surface.



Yes, that all makes perfect sense to me now. I erroneously assumed you didn't agree with what I was saying. 

I always do my own calculations for these effects. A while back, I saw a reference to a fellow who did a spreadsheet to calculate both nod and wag from a set of measurements. I contemplated doing that too. I may even do it yet. But fundamentally, it isn't a critical measurement. It's just something we would all like to minimize and/or at least directionally understand how it might affect our work.


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## Susquatch (May 28, 2022)

PeterT said:


> I've seen people discuss bed wear effect, but have not seen much reference quantifying it relative to a cylindrical datum surface.



I understand. And I agree. My own mind tends to be easily lured into chasing such things too. I love rabbit holes...... 

However, I think the whole subject of lathe head alignment is generally so badly misunderstood by so many others that I prefer to try and keep things simple. It's hard enough to explain the difference between tail stock alignment and head alignment without adding in the effect of saddle and way wear. So I simply didn't mention it. Then again, I didn't mention ambient temperature, machine warm-up, indicator contact angle, cutting force, speed, etc etc etc either. 

Of course, omitting things like that then invites criticism from others who know more and don't like to oversimplify. Sometimes you just can't win. 

It doesn't stop me from trying to help others where and when I can though. It's the least I can do given all the help others have given me. 

Anyway, thanks for clarifying Peter. It is much appreciated.


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## StevSmar (May 29, 2022)

@Susquatch , you know modelling a lathe in Fusion 360 and then applying loads to the supports would be a great project for someone learning Fusion…

(I suspect you’d need a one month subscription once everything is modelled up, to do the analysis though)


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## Susquatch (May 29, 2022)

StevSmar said:


> @Susquatch , you know modelling a lathe in Fusion 360 and then applying loads to the supports would be a great project for someone learning Fusion…
> 
> (I suspect you’d need a one month subscription once everything is modelled up, to do the analysis though)



I think that would be a great idea for someone who has more free time than I do. I'm quite familiar with modelling complicated parts and assemblies. I used Catia before I retired. In my opinion, modelling a lathe would be way too much work for me.


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## StevSmar (May 30, 2022)

Susquatch said:


> I think that would be a great idea for someone who has more free time than I do...


It certainly does take an exponential amount of time the more complicated the model is!

I really liked the cardboard model Joe Pieczynski has at about the 3:30 mark of his video:
Lathe Leveling - Waste of Time ????
This was a perfect level of detail for me to visualize what was happening as I experimented.


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## Susquatch (May 30, 2022)

StevSmar said:


> It certainly does take an exponential amount of time the more complicated the model is!
> 
> I really liked the cardboard model Joe Pieczynski has at about the 3:30 mark of his video:
> Lathe Leveling - Waste of Time ????
> This was a perfect level of detail for me to visualize what was happening as I experimented.



Unfortunately, I have an overactive imagination. Don't need videos. Lots of things involving beds happen in my mind..... 

Something for you to think about..... Imagine what went on in the minds of the people who developed, tuned, and used lathes back in the early days! Those folks were truly gifted.


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## StevSmar (May 31, 2022)

Susquatch said:


> …Lots of things involving beds happen in my mind.....


Yes, I know I dream of beds too. Lathe beds,  Road beds, Superconductor Electromagnetic beds, garden beds, beds of roses, creating bed-el-em etc. There’s probably other beds to dream of I guess.


Susquatch said:


> Something for you to think about..... Imagine what went on in the minds of the people who developed, tuned, and used lathes back in the early days! Those folks were truly gifted.


I’ve been getting interested in industrial history. How did we get to today. Interesting how there was no widespread need for machining accuracy until until the steam engine (from what I’ve read so far). How did someone work out that rubbing three stones together made them exceptionally flat.

(There is no such thing as an electromagnetic bed that I know of, that was a “this story has been modified for dramatic purposes”, I had to think of some type of bed that was related to Electrical Engineering)


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## trlvn (May 31, 2022)

StevSmar said:


> I’ve been getting interested in industrial history. How did we get to today. Interesting how there was no widespread need for machining accuracy until until the steam engine (from what I’ve read so far).



I ran across a book that you might find interesting:

The Perfectionists
How Precision Engineers Created the Modern World
by Simon Winchester, 2018

Very much in the field that you mentioned although I don't recall if it described lapping to create a reference surface.  Might have but I don't recall.  It was available to borrow from our local library system.

Craig


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## David_R8 (May 31, 2022)

trlvn said:


> I ran across a book that you might find interesting:
> 
> The Perfectionists
> How Precision Engineers Created the Modern World
> ...


I have read that book and it's excellent!


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## historicalarms (May 31, 2022)

StevSmar said:


> Yes, I know I dream of beds too. Lathe beds,  Road beds, Superconductor Electromagnetic beds, garden beds, beds of roses, creating bed-el-em etc. There’s probably other beds to dream of I guess.
> 
> I’ve been getting interested in industrial history. How did we get to today. Interesting how there was no widespread need for machining accuracy until until the steam engine (from what I’ve read so far). How did someone work out that rubbing three stones together made them exceptionally flat.
> 
> (There is no such thing as an electromagnetic bed that I know of, that was a “this story has been modified for dramatic purposes”, I had to think of some type of bed that was related to Electrical Engineering)


Dont know how it was arrived at but I have been very close to a lot of stones that were made flat to fit together 3-4000 yrs ago (Greek Parthenon and a # of other structures over there) but I can tell you it is amazing to see columns of stone from that era that you still couldnt get a cigarette paper between them. the joints between stone sometimes are only visible by very close observation.


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## David_R8 (May 31, 2022)

historicalarms said:


> Dont know how it was arrived at but I have been very close to a lot of stones that were made flat to fit together 3-4000 yrs ago (Greek Parthenon and a # of other structures over there) but I can tell you it is amazing to see columns of stone from that era that you still couldnt get a cigarette paper between them. the joints between stone sometimes are only visible by very close observation.


I saw the same thing in Peru at Mayan ruins. Stone blocks the size of small cars fit together with unbelievable precision. The most amazing to me were stone blocks connected together by with keys made of different stone from a different quarry.


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## StevSmar (May 31, 2022)

trlvn said:


> I ran across a book that you might find interesting: The Perfectionists, How Precision Engineers Created the Modern World, by Simon Winchester, 2018…


I REALLY enjoyed that book and it’s what set me down the path of learning about industrial history. I’ve read other books by Simon Winchester and I’ve found them tough going- this one I limited myself to one chapter a day so I could spread the enjoyment.

I should re-read it over the summer. I’ve tried to find books with a similar treatment but have not yet.


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## opensourcefan (Jun 10, 2022)

TRANSACTION CONCLUSION, finally. 

I finally got my replacement chuck which was also sudo compensation for all the troubles with this lathe. We agreed on this being sent to me as compensation and then when the time came to ship I got the standard "there's a problem" which I heard before.  All of a sudden, someone who claims to ship packages all day long was surprised by the shipping cost for this and wanted money from me to cover some of it. I didn't tolerate that even a little and he eventually shipped it after a back and forth which I will spare you all from.

Also FWIW, I contacted PayPal and they stated that if there was a deliberate attempt at stalling to pass time beyond the 180 day protection that they would open a claim without issues. They were ready to do it but I held off pending receipt of this package, it's a good to know anyway. 

This brand seems to be considered the better of the cheap chucks from China. It still required a complete disassembly and a lot of deburring. It actually would barely turn on arrival, it was bad, worse actually than the cheap junk that was installed on the lathe in the first place. However it's build is much more solid and refined compared to the other, which sounds weird to say after the previous sentence. Once deburred and cleaned up it feels excellent. It is consistently running out at .001" which I'm okay with.


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## Susquatch (Jun 11, 2022)

opensourcefan said:


> TRANSACTION CONCLUSION, finally.
> 
> I finally got my replacement chuck which was also sudo compensation for all the troubles with this lathe. We agreed on this being sent to me as compensation and then when the time came to ship I got the standard "there's a problem" which I heard before.  All of a sudden, someone who claims to ship packages all day long was surprised by the shipping cost for this and wanted money from me to cover some of it. I didn't tolerate that even a little and he eventually shipped it after a back and forth which I will spare you all from.
> 
> ...



I always marvel at the consistent failure to execute the manual details for something that comes from a country with supposedly low labour costs. 

Anyway, glad you are happy with your diamond in the rough. I enjoyed following your journey. Thank you!


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## StevSmar (Jun 11, 2022)

opensourcefan said:


> TRANSACTION CONCLUSION, finally.
> 
> I finally got my replacement chuck which was also sudo compensation for all the troubles with this lathe.


That’s great you were able to finally complete the transaction. Sounds like you’ve got a better replacement chuck too!

I still really like the colour of your lathe…
(because it reminds me of a model plane I built as a kid, and it’s close to the colour of the second hand kitchen cabinets we had at the cottage (we painted the backsplash in the kitchen the same green out of fondness…))

(My apologies I contributed to taking your thread off topic with the discussion on alignment… we should have taken that to another thread and not polluted your thorough summary of your purchasing experience with an alignment side discussion)


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## opensourcefan (Jun 12, 2022)

GEARBOX REVIEW

Well, the one thing I didn't take apart and I should have sooner. Below you will see pics that are kinda disturbing considering these were intentionally installed on a new lathe touting quality. It shifted fine into the gears but it didn't feel repeatable or solid, now I know why. 

As per the Grizzly manual for this lathe model the gears should be lubricated with grease and serviced annually. As you will see in the photos there isn't any grease on the gears just something (don't know what) on the brass shifting fork #341. You will also see some miss-drilled detents on the shaft bracket #306. Due to the position of the detent hole on the knob, the detents in use were the two on the right and the screw head phillips slots. The shaft #311 is disgusting, I don't think I could have done this poor of a job intentionally. The design is bad as well leaving only an 1/8" bearing surface for the shaft to rotate on. There are also a couple miss drilled set screw locators on the shaft for the knob. 

All I can say is, wow! Guess I'll be redesigning and making some bits.


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## Tom O (Jun 13, 2022)

Can you check gear engagement with the detents showed it might just be right after all but you would think that it would be in the middle.


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## opensourcefan (Jun 13, 2022)

Tom O said:


> Can you check gear engagement with the detents showed it might just be right after all but you would think that it would be in the middle.


I did, the left detent wasn't in use. Neutral is the far right detent. I think that bracket came off of another machine or it was a left over part.


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## PeterT (Jun 13, 2022)

That doesn't look like too difficult a part someone could make for you as a fresh blank & you could re-do the detents. @Tom O is right, it may not be equal purely as a result of the mechanism throw itself. But if the position is out & engagement difficult, that blows & must be dealt with. It has the telltale signs of how these machines are made (right up to & including my Taiwan 14x40). They line it up by eye & out comes the hand drill. Also check that maybe either collar has not come loose on its shaft. ie by loosening & shifting maybe there was a better position & now its out of phase.

Just keep telling yourself : its a KIT, I LIKE building KITS!


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## opensourcefan (Jun 13, 2022)

I've already made the replacement bracket modified with a bearing surface. Ran out of parting inserts so it's on the lathe waiting while I stare at the hacksaw  

Rebuilt the shaft as well. I'll add the detents once it's all together. I was running without one detent this whole time anyway. 

The beauty of having the gearbox is neutral. Less noise, less wear and tear, and more available power.


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## Susquatch (Jun 13, 2022)

opensourcefan said:


> while I stare at the hacksaw



So that's what your avatar is all about!


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## opensourcefan (Jun 13, 2022)

Okay, it is awesome now, I absolutely love it. Loud audible detent clicks, firm locating and a very solid feeling function. That's just testing without any lube either .

A couple pics of the bracket I turned. Detents are close to the original but the knob was correctly positioned so all three are being used and neutral is actually in the middle. I also altered the design a bit to include a bushing area for the shaft to hold it more rigidly. 

Now I know it's going to be good.


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## PeterT (Jun 14, 2022)

Good work. 'kit' building can be a rewarding hobby lol


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