# Colchester Student 13"



## ScottyM (Jan 11, 2020)

Hey Everyone!

A few months ago I picked up a 1962 Mk1 Colchester Student Dominion with 13" swing and 24" between centres. I had been looking for a decently stout lathe in this size for a while and was originally wanting one of the older Standard Modern 12" (or bigger) Utilathes. This one popped up within reasonable driving distance and since I have always liked the roundhead Colchester's decided to pull the trigger. It came with a three jaw chuck, steady rest, follow rest, multifix toolpost, 4 position toolpost and a decent amount of tooling.

The guy I bought it from had owned it for 4 years and had hardly used it. He told me it previously belonged to a hospital, the older gentleman he bought it from had been the sole operator since the lathe was new and bought it when the hospital wanted to sell.

First things first was getting it home. It was out near the Saskatchewan/Manitoba border, ~10hrs one way from my place. I left on a Friday after work and made it there that night. Went and picked it up first thing the next morning and was back on the road headed home with the spoils. It was a miserable day floating around 0 when loading and snow/rain. I wrapped it to within an inch of its life and was so glad it did. It snowed hard for the first few hours of the drive still hovering around 0 out, the temperature then plunged to a nice -20. The wrap job isn't pretty but it held, was interesting trying to seal everything off.










Because of the temperature drop after rain/snow there was a some frost when I unwrapped it. Not wanting it to rust in any spots I wiped everything down and spent a couple hours cleaning it, finishing with a coat of wd40 to drive out any remaining moisture. The thing had a good layer of oil and grime on it so I don't think rusting was even remotely possible.

I then pulled it off the trailer, wired on a new plug and ran it through some initial tests. Everything seemed to work as it should, ran smooth and without issues. I was happy with what I was finding and what it could take for cuts.

After a little fun I started the tear down. Any time I get a new machine tool I tear it down to the bare nuts and bolt, clean out the grime, oil/lube properly and take stock of what needs replacing or fixing. I'll post what I've gone through to date below so these posts don't get too out of hand. I plan to rebuild this lathe to better than new, scraping and all. I want to bring everyone along for the journey since hopefully you all enjoy this stuff just as much as I do!


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## YYCHM (Jan 11, 2020)

Nice looking machine.  What did that set you back if you don't mind sharing?


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## ScottyM (Jan 11, 2020)

Once the machine was sat where I wanted it, I pulled the headstock cover to inspect. Opening it up revealed all the gears to be in great shape. The spindle has no play in it and almost no runout with a tenths indicator on it. Just recently I've noticed that the input shaft and idler have some play due to worn bushings. That's an easy enough fix and I hope to tear down the headstock soon to get some measurements and make some new ones, haven't done so yet because I don't have bronze on hand in the right size.






Next up was getting the topslide and cross slide off followed by the apron and saddle. The topslide and crosslide both have some wear but not much, around a thou at the worst when measured on a surface plate. The crosslide operates smooth across its entire travel without getting tight. The topslide gets tight at the end of its travel when extended out. Further inspection brings me to think the gib is ever so slightly warped and causing this. Nothing major, very happy still as this machine is almost 60 years old and could be a lot worse. 

I completely disassembled both, cleaning lead screws, nuts, threaded holes etc. This included the dials on the handwheels. These were terrible to reassemble as there are spring loaded balls within to keep pressure on the dial, allowing to set 0 with it staying in place once released. There are a lot of holes on the top of the cross slide that were packed with chips. This thing seems like it cut mostly brass/bronze in its previous life. Both were reassembled after the deep clean and set to the side.






Getting the saddle and apron off was a bit more involved. The saddle is held on with a bracket on the underside of both ways. I didn't see a good way to get the one on the operator side off without pulling the apron off first. To get the apron off you have to remove both the leadscrew and feed shaft. The feed shaft has a coupling outside of the gearbox making it easy to remove. To remove the leadscrew you have to open up the gearbox and remove some gears and collars that retain it from within.

Components on top are removed when pulling out the leadscrew.









With the leadscrew out I was able to pull off the apron and saddle. Can still see old scraping on the areas that were covered. The saddle has wear on the underside but overall in good enough shape to run until I can rescrape. One thing I did notice was poor location of the oil grooving, on the flat way the hole is right on the edge so when oil is pumped in most spills off the side. I will redirect the holes and extend the grooving. Gave it a good clean and set aside. Also replaced wipers.


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## ScottyM (Jan 11, 2020)

YYCHobbyMachinist said:


> Nice looking machine.  What did that set you back if you don't mind sharing?



Thank you! Don't mind at all, paid $3k for it. I thought it was a great price given the shape and coming with all steady's. The multifix that came with was brand new and some beautiful skoda live centers that were never used still go for around $1700 total.


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## YYCHM (Jan 11, 2020)

What's a "multifix"?


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## ScottyM (Jan 11, 2020)

YYCHobbyMachinist said:


> What's a "multifix"?



It's a type of toolpost that lets you change angles to repeatable positions very quickly. I've never owned one until now, now don't think I could buy a different style.


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## ScottyM (Jan 11, 2020)

Next up was the feed shaft worm box. When pulling out the feed shaft, the worm box (has the gearing and lever to select surfacing or cross slide feeds) comes off as well. This thing was beyond packed with chips and old solidified oil. The first picture is after I had already cleaned some of it out. Surprisingly there wasn't any serious damage to the gears, can't complain about that. the coupling on the lower right is what connects the feed shaft to the gearbox, it also includes a ball bearing clutch which is such a beautifully simple design.














The bushings where the feed shaft rides were very worn but easily replaceable. So I drove them out and turned some replacements out of PTFE. Originally this was just temporary until I had some bronze but they might stay as I'm sure the PTFE will last for quite a while.














Gave the leadscrew and feed shaft a good scrub too, both are like new.






Can't forget the feed screw coupler, pulled it apart and cleaned/oiled.


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## ScottyM (Jan 11, 2020)

The apron was also covered with chips and solidified oil, but again no serious damage. Tore it apart and scrubbed everything down, lapped any burrs/highspots and reassembled. I always make sure to thoroughly clean the oil ports. No good cleaning everything else if the next time you oil it, it flushes grit right back onto the surfaces.














After a good cleaning.














At this point I started cleaning the bed and chip tray out getting ready to start reassembling. Started top down, picture was mid clean between the ribs of the casting. The ways are in great shape for being unhardened, I have yet to doing some serious measurements but after a quick pass with a master level I don't expect more than 2.5 thou. The scotch-brite and sand paper was also just for the chip tray where I did a couple test spots to see what I was in for.






No pictures but the feed shift lever was removed and cleaned as well as the rack.

Also thought I should mention I am moving all my machine tools to a different area of my shop, don't have my normal workbenches set up here and not many places to set tools. All this teardown is messy work and only made worse by the tools everywhere. Apologies to all that these pictures may have driven up the wall, trust me, I was the most affected!


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## Tennalum® 7068 (Jan 12, 2020)

Nice find and something that sounds like it was barely used or run hard. 

Love the clean up pics and something that I have done before with a old much larger VDF lathe. I wiped out the entire headstock as the bearings were shot and needed replacing.


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## PeterT (Jan 12, 2020)

Your tear down pics & descriptions are great. That looks like a a nice machine.
What kind of spindle nose is that? How is the motor configured (voltage/phase).


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## ScottyM (Jan 12, 2020)

Pulled the chuck apart the other day, expected a lot more in there! Pictures below are as it was when opened. Wipe down and back together it went with a light oiling.










This is where the lathes at right now! mostly reassembled with just the feed shaft remaining and much cleaner. Always nice operating something after a teardown and cleanup since you know it's good, also know the machine inside and out if it starts giving you lip.






what's left on the list for the near future:

- Cleanup gears at the back
- Teardown and replace headstock input and idler bushings
- Replace belts
- Tailstock
- Fab splash guard

For the remainder of the winter my plan is to get the lathe to 100% mechanically, then this spring/summer when I can really tear it down I'll scrape any surfaces that need it and repaint. Stay tuned and happy reading!


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## David_R8 (Jan 12, 2020)

Wow, that looks fantastic, great find!


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## ScottyM (Jan 12, 2020)

Tennalum® 7068 said:


> Nice find and something that sounds like it was barely used or run hard.
> 
> Love the clean up pics and something that I have done before with a old much larger VDF lathe. I wiped out the entire headstock as the bearings were shot and needed replacing.



Funny you should mention that! My cousin has a nice VDF lathe that I helped him setup the other week. The headstock is a little out though and he's got the bug to work on it again. I sense a teardown coming. Awesome machine!


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## ScottyM (Jan 12, 2020)

PeterT said:


> Your tear down pics & descriptions are great. That looks like a a nice machine.
> What kind of spindle nose is that? How is the motor configured (voltage/phase).



Thanks Peter!

Spindle is an american L0 taper, little more on the uncommon side now but a solid simple design in my opinion. Looking for a nice collet chuck and 4 jaw at the moment, just missed out on a rubberflex in Edmonton. Maybe someone here got it?

Currently has 1.5hp single phase motor. This would have come with a 3hp 3 phase motor and plan to go back to that. Always try to avoid single phase on lathes this size for the vibration issues. Cant imagine the lathe with 3hp. I was tossing some heavy cuts at the current motor and didn't even blink.


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## Tennalum® 7068 (Jan 12, 2020)

The VDF is my brothers machine and it’s a beast you can run that machine very hard if you want too. My brothers machine is bigger than the one you got pictured there.


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## Dabbler (Jan 12, 2020)

I love Colchester lathes!  My very first lathe was a clone made in Taiwan, and I'm still using it. (a 1930's design with some weird 1940s changes!)  You will get great service from it!

I've heard from JohnN that VDF lathes are beasts!  also a very nice find!


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## Brent H (Jan 12, 2020)

Awesome find and clean up/restore!

I just missed a Colchester Student in the spring cause I was stuck at work - got a nice Standard Modern though....The Older Colchesters are great and well built lathes.  We have a Colchester/Clausing at work here and it has some let downs in its construction.  The compound is pretty weak and poorly designed compared to older models.  We have had to replace it due to wear after 10 years and not, what I would call, intense use.

Wicked tool post, you will love it....very jealous ...LOL

Looking forward to more of your posts!


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## CalgaryPT (Jan 12, 2020)

Are those Acetal/Delrin bushings you made?


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## ScottyM (Jan 12, 2020)

@Tennalum® 7068 
Yeah that's a little guy as far as VDF lathes go!

@Dabbler 
I also love the Colchester's and was happy to find one. They are very well built machines, great designs made to last. I especially appreciate all the wear areas being easily replaceable. One of my favourites in terms of looks. I seem to like the styling of that period as I'm rebuilding a 1963 F100 unibody at the moment as well. 

@Brent H 
Thank you! Isn't that the worst when you see a great find but miss out because of those dang responsibilities  What size/year Standard Modern do you have?

@CalgaryPT 
They very well could be! That was the only bearing material I had on hand in the right size and wasn't labelled. The general slipperiness of it makes me think its PTFE but my hands were also nicely impregnated with oil at that point in the rebuild.


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## RobinHood (Jan 12, 2020)

ScottyM said:


> The bushings where the feed shaft rides were very worn but easily replaceable. So I drove them out and turned some replacements out of PTFE. Originally this was just temporary until I had some bronze but they might stay as I'm sure the PTFE will last for quite a while.



you caught those in the nick of time before it wore into the casting.

that should last a very long time. The key will be to keep the feed rod clean as any hard particles will easily embed in the soft PTFE and abrade the shaft quickly.

i make it a habit of turning off the feed system when not in use


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## CalgaryPT (Jan 12, 2020)

RobinHood said:


> you caught those in the nick of time before it wore into the casting.
> 
> that should last a very long time. The key will be to keep the feed rod clean as any hard particles will easily embed in the soft PTFE and abrade the shaft quickly.
> 
> i make it a habit of turning off the feed system when not in use


PTFE, Acetal (POM-C), Delrin (POM-H)...all terrific material and I am always impressed with how well they work. Great fun to machine as well.


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## Brent H (Jan 12, 2020)

Hey ScottyM, 

My Utilathe is the 10x20 model.  Not sure of the year of manufacture : Serial number is U530.....sounds like a WWII U-Boat - LOL   I have a write up on this forum about the work to restore it and making parts.  Currently finishing off the taper attachment when I get home and will be making some gears for the apron when I get a few things made up for the mill and gear cutting.  

I would guess its somewhere late 60's or so as there is some carry over with the 11"  series 2000 with respect to the cross feed and having wedge type gibs instead of flat set screw type.   If you ever come across any parts for the beast let me know!  I will be trying to make up a metric set of change gears as well.....


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## ScottyM (Jan 12, 2020)

@RobinHood
Right! Haha just measured them actually, only 11.5 thou left before it would have started into the casting!

I also never run feeds system if not using, one less thing to get your fingers wrapped around and less wear. I'm tempted to make a 2-piece bushing, inner bush keyed to the shaft so it rotates with and its not using the shaft as a bearing surface. With the amount of wear there was it clear there's room for improvement.






@CalgaryPT 
Soooo satisfying to machine, the sound it makes as you zing through it is what dreams are made of.


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## Brent H (Jan 12, 2020)

Holy smokes!  Colour that bushing gone!  wow - great timing.  Might work well if the bearing bronze you used for a replacement was oil impregnated and a harder high load type? 

If it is the feed drive, any possibility of converting to a roller bearing assembly?  If the housing is long enough you could use a ball bearing suitable to absorb axial loads in both directions - would cancel out the shaft wearing on another surface?


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## ScottyM (Jan 12, 2020)

It's -30 where I'm at today so decided it was a good afternoon for some shop time.

I wanted to clean up the steady and follow rests. These are in great shape other than the grime and flaking paint. I am itching to start painting but must be patient, why do all the good paints have to be so bad for you?










Disassembly went smooth, one thing to note is there are little copper balls under the set screws to lock the fingers in place. I didn't notice at first and almost lost them. When I get another mill I'd like to slot the fingers and turn down the ends of the set screws to index the slots. This would also give a flat bottom contact for securing with the set screw, I don't like the point contact of the balls for this. When slotted I can make some caps with ball bearings.

Went through and took off any high spots and burrs after a good clean. This stuff was hard on the finger tips, but all worth it seeing the end result.


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## ScottyM (Jan 12, 2020)

Brent H said:


> Holy smokes!  Colour that bushing gone!  wow - great timing.  Might work well if the bearing bronze you used for a replacement was oil impregnated and a harder high load type?
> 
> If it is the feed drive, any possibility of converting to a roller bearing assembly?  If the housing is long enough you could use a ball bearing suitable to absorb axial loads in both directions - would cancel out the shaft wearing on another surface?



That's also another option I'm considering. The bushings have a wall thickness of 1/8" and not enough meat to bore the casting any larger, needle rollers are a no go. I do have plenty of room on either side to mount ball bearings on the outside of the worm box. Really I think the bushings are undersized for the load they see.


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## PeterT (Jan 12, 2020)

I'm not sure if I am looking at the equivalent part to my 14x40 powerfeed drive line. Did you check for wear on the casting adjacent to worm gear? (red arrow).

Mine was a crappy setup to begin with, but the worm gear is capable of wearing out the cast iron bracket. I tossed the cast iron bracket, made new blocks & installed mirrored bronze bushings on either side so it has something sacrificial to bear on power feeding in or out.


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## RobinHood (Jan 12, 2020)

You probably already know this, on the newer Mark2 models they seem to have improved the apron feed bushing.

here is a video of a fellow working on a 1964 Mark2. You can see the much beefier bushes starting at about 0:30. 




perhaps you could model your future Improvements after the factory upgrades


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## ScottyM (Jan 13, 2020)

@PeterT - Luckily no wear in that section! Shaft had a great fit in the casting and very little side to side play on the worm/gear combo. You can see in the pictures of the bare casting that the surface isn't eaten away at all - lots of bearing area on the side of the worm and not too much pressure due to the gear reduction I'd say.

@RobinHood - I hadn't looked closely at the mk2 apron but seems like a much better design all around, not to say that the mk1 is bad by any means. Might be able to take some inspiration from it! What Colchester are you running? I was reading through your taper attachment build and tried to find what specific model with no luck.


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## RobinHood (Jan 13, 2020)

ScottyM said:


> What Colchester are you running? I was reading through your taper attachment build and tried to find what specific model with no luck.



its a Colchester Master 2500. It had a lot of rust on it and the spindle was “seized”. Not really seized, just someone managed to get it into two gears at the same time and they were not able to get it going again.
It required the whole headstock gearbox to be disassembled because the shift forks are at the very bottom of the HS (all the nested gears and the shafts had to come out) in order to free the thing up.

While I was in there, I just replaced all the bearings (except the spindle bearings - they were in excellent shape), repaired the clutch fork, improved the lubrication system (it has a ”dry sump“ system with no oil bath in the headstock but rather an external tank and pump), improved a gear shift fork for better gear mesh and replaced a worn bushing (caused by the bad factory gear mesh - a weakness on the Master).

It runs really nice now. I did make a all of the missing parts in the taper attachment as well (You saw that).

Now I just need to make a 56T change gear (to give me the full range of 39 Metric threads, 45 SAE threads, 18 Module and 21 DP threads ((with other gears, even more threads can be cut))); a steady and a follow rest (unless I can find them reasonably priced - which at the moment does not seem possible...)

link to clutch fork repair: https://canadianhobbymetalworkers.com/threads/clutch-fork.1185/

link to shaft repair and gear bushing replacement: https://canadianhobbymetalworkers.c...-and-gear-bushing-replacment.1186/#post-11760


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## ScottyM (Jan 13, 2020)

@RobinHood - Awesome stuff! I will be replacing the equivalent bushing on mine. Looking inside the headstock and at gear stack up from the manual I don't have the same hardened retaining clips, just one long bushing. Hopefully won't run into the same scoring issues on the shaft.

On a side note, how do you go about getting the smaller pictures on your write ups until clicked? I'm not too fond of how mine have been showing full size, text gets lost in my opinion.


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## Brent H (Jan 13, 2020)

@ScottyM  I think you just use the attachment (Attach Files) button.  I wanted to attach the manual I made up for the Utilathe but it didn't work.....will try again on my overhaul restore thing


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## RobinHood (Jan 13, 2020)

ScottyM said:


> On a side note, how do you go about getting the smaller pictures on your write ups until clicked? I'm not too fond of how mine have been showing full size, text gets lost in my opinion



once you upload your picture, you should see two choices after “insert” in inverse video: one is ”Thumbnail” the other is “Full image”. I use Thumbnail for the most part.

here is a sample of a Thumbnail


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## RobinHood (Jan 13, 2020)

Brent H said:


> I wanted to attach the manual I made up for the Utilathe but it didn't work.



there might be a file size restriction or some other constraint that prevents you from uploading the file.

i am sure one of the Admin wizards will chime in and be able to help out...


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## Hruul (Jan 14, 2020)

Hello ScottM, awesome find!! Where did you find that lathe for sale??


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## ScottyM (Jan 18, 2020)

Bad news! I have some shafts and bushings to make...

As mentioned previously, there was some play in the input shaft and and second shaft (what I was previously calling the idler shaft). I was hoping the bushings were just worn and the shafts would be good, but also knew better. 

Right off the bat, I found the cause during the teardown. When going to take off the belts and pulley's it was clear that the belts were way too tight. Like wayyyy too tight. This jacked the shaft and caused the fluid film for the bushings to disappear at the pressure points. This wasn't helped by the input shaft being two pieces, the shorter sections allowing more movement and less resistance to the moment on the shaft. This only got worse as the shafts/bearings wore. The pictures below try to show the play in the pulley and the split input shaft.




 




I cut the belts since they needed replacing anyway. Pulleys came off and showed the braking mechanism, good news here is that there is lots of meat left on the pads, that would have been a pain to replace. Off came the mechanism and bushing housing. The input shafts, secondary shaft, associated gears and bushings quickly followed. 




 


 


 




And here they are, there was lots of bearing material and sludge in the bottom of the head after draining the oil. This sludge also coated everything else. You can see the heavy wear/grooving on the shafts, and the uneven wear on the shafts that were jacked due to the excessive belt tension. What's funny is some of the bushings pressed into the gears are still perfectly on size, they got embedded with the sludge and wore the shaft instead. I also suspect some of these bushings were replaced at some point without anything being done to rectify the shafts. Recipe for recurring failure.




 


 





 




The good news? There were no big chunks loose in the head and all the gears are still in great shape! 

Looks like it's time to start making. But hey, I love to buy all this machining equipment and make parts. What am I supposed to do? Act mad now that I have to do it? Bronze has been ordered and I am chomping at the bit to get started!


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## Dusty (Jan 18, 2020)

Hello ScottyM, before starting into making new shafts have you considered spray welding the damaged portion then turning same down to size. Just a thought which might save you hours of work and frustration.






Bill


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## PeterT (Jan 18, 2020)

Keep the great pictures & refurb progress coming. Fascinating stuff. 
What alloy material will you make the shaft from?
Is the gear on the end integrally cut or pressed on?


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## Dabbler (Jan 18, 2020)

Another approach is to turn and polish the shafts to concentric by taking minimal material, then making extra thick bushings to accommodate.  Saves a lot of work making new shafts, and for light (hobby) use, ti should suffice.  You can always make new shafts later and re-bore the bushings.


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## ScottyM (Jan 19, 2020)

@Hruul - Apologize I missed your post last time, I picked it up in eastern Saskatchewan after finding on kijiji.

@PeterT - Thanks Peter, I'm glad you're enjoying it! I have a lot of 4140 and some W2 tool steel that are both great choices. Both are very tough and heat treat beautifully. I will either case harden so the bearing area is very hard while still preserving the toughness from a softer inner shaft, or through-harden and temper back. Both would work but I'm leaning towards through hardening as this is a smaller shaft and I want to limit the deflection that originally caused this damage.

The gear on that shaft is integral, that one has the least wear and simple features so I will most likely grind out the wear and just make it up in the bushings. Also thick enough to not worry about preserving material. If for whatever reason I do have to make a new shaft, I'll part off the gear with an inch or so of the shaft left, turn it down to a smaller diameter and press into a recess on the replacement. Pin through for good measure.

@Dabbler @WilliamG - I have always wanted to try spray buildup but don't know anyone with the equipment, looks like a lot of fun. That and the thicker bushings are both great options. I should have worded my post differently. I have yet to take good measurements of the wear on the shafts as I went straight to removing the spindle after that. Depending on what kind of wear I'm dealing with I'll pick whatever fix will work the best for each.

These are the options I'll pick from:

- Turn/Grind down worn area and replace with hardened sleeve
- Turn/Grind down worn area and make up difference in bushing
- Build shaft back up with TIG and turn/grind back to size (controlled preheat and cool down to prevent warp)
- Build new


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## Hruul (Jan 20, 2020)

Thanks ScottyM.  I must not check Kijiji often enough, I never see anything on there anywhere near me.  Good luck with the repairs.

Lee


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## Tom O (Jan 20, 2020)

I haven’t tried the spray welding yet I have the oxy/ act up and running ( hoping not to blow myself up like SV Seeker!)  but if your in Calgary and want to give it a go give me a holler.


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## ScottyM (Jan 20, 2020)

@Tom O - I've never watched his channel but that is terrible, I hope he recovers. All the confined space training I've done in my life the thought of explosions has always made my skin crawl. That video is pretty terrifying, almost doesn't seem real as stuff like that is usually caught on some 240p security camera in who knows where.

That being said I appreciate the offer! Might take you up on that next time I'm in Calgary. Think I'll leave the acetylene alone for a few days though after that.


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## Tom O (Jan 22, 2020)

Turns out SV Seeker pranked everyone! Another idiot to un follow!
https://ktul.com/news/local/tulsa-b...nk-stirs-anger-and-support-online?jwsource=em


Sent from my iPad


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## Brent H (Jan 31, 2020)

Holy smokes!

that guy is a complete dink.

"_The only people on a boat that you can count on is your crew. There's no 911. No ambulances. You count on the people around you," Jackson said. "So, why do I filter? Because I want the right people around me._"

That “wanna be” sailor is the reason mutiny is a word.  People should not be impressed with stupidity.  Hopefully any patrons pull out and his boat is deep sixed.  What a moron


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## Tom Kitta (Jan 31, 2020)

Yeah looks like the guy faked an injury to... figure out whom will still be around after he revealed it as a fake?  I am little bit confused by his experiment or psychology behind it. I definitely would not want anyone on my mountaineering expeditions that fake any injury or lie in any shape and form. Decisions made based on that lie could effect not just success of the expedition but lead to a disaster. 

I rebuild this week a small part by welding it up. It does work and I did it few times. Through having a welding positioner for round things would help. Just careful that you don't accidentally heat treat it.


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## ScottyM (Feb 1, 2020)

Seeing all the crud that was in the headstock I went ahead and continued to tear it down completely. This all happened the same night as I pulled the input and secondary shaft but am just now finding time to post it all.

To get the spindle out started with the retaining nut at the back. You can see where a precision mechanic previously used a punch delicately remove... I will have to clean that up. I don't bother with spanner wrenches as no matter how many you have, it's never the right one. Nuts like these almost always have a set screw, I like to thread a bolt in (not bottoming out) and use a punch on it. It preserves the threads, is in there secure and acts as a sacrificial piece instead of the nut. Also the softer metal absorbs any harshness of impact. I put a couple witness marks then spun it off.




 


 


 


 




There was also a retaining nut inside the head at the front. This one spun off easy as it had lived in oil. I undid the bearing cap at the front of the headstock then shot some freeze spay through the bore of the spindle to shrink a bit. The spindle came out pretty easy, taking time to move forward grabbing each piece as it came free. No pictures as all hands were accounted for. Overall everything is in good shape just needs a clean.




 


 


 




Anything else that went into the headstock was pulled out so I could clean out all the bearing material and wonderful sludge from the headstock. First picture is after I had already wiped some out. I made sure every nook and cranny was gotten to.


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## ScottyM (Feb 1, 2020)

All the little components and levers got a good scrub and inspection then started to go back in, fixing anything that needed it along the way. First up was the feed reverse lever, this thing had no hard stops but didn't seem to cause damage by doing so, confirmed when I could get a good look with the oil drained. After taking it apart I found a little pin inside that had sheared. I drilled out the broken stud and replaced with some tig wire. I used a chunk from an end that had been used as it had a bit of heat treat making it harder. Putting back together I aligned the gear positions with where I wanted the lever. Also reinstalled the high-low gear change lever and clean up the oil level sight glass.




 


 


 


 




I flushed out the outer bearing races and the spring loaded cap for the rear race, cleaning up the casting as well. The front outer race is an interference fit into the headstock. It was -40 when I did this so a few minutes outside and it slid right into place. The rear outer race is a sliding fit so the spring loading can move it as needed.




 


 


 


 




A couple shots with all the little pieces and levers back in place. Everything got the same going through.


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## ScottyM (Feb 1, 2020)

The bearings got a complete going through. Each one taken apart, thoroughly cleaned/scrubbed and inspected, then reassembled. I kept each roller in the same position in the cage to ensure any variations on how they wore together remained. A light oiling then bagged until they are reinstalled. All was done using lint free automotive paint prep wipes and a lot of effort went into keeping everything perfectly clean before reassembly and bagging. Just like that, all three were done.






























All the spindle gearing looked great, cleaned and filed down any burrs. The chuck locking ring had a lot of the bluing worn off and looked rough. I stripped the bluing with some warm vinegar and gave everything a once over with a soft wire brush. Looks much better in my opinion now that is has a consistent finish but I might re-blue. All parts are ready to go back on once the spindle is done.


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## ScottyM (Feb 1, 2020)

@Tom O @Brent H @Tom Kitta - That guy has some issues for sure, but, not worth any more time. For those shafts if I do end up welding, I have the luxury of some heat treating experience and equipment. Worked for several years as a heat treater for large vessels and piping etc. and enjoy doing the stuff! Was already thinking I'd heat treat anyway for some fun!


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## John Conroy (Feb 1, 2020)

Nice work Scotty. It's going to be better than new when you are done.


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## Hruul (Feb 2, 2020)

Looks great and I enjoy the pictures.  Keep it coming.


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## ScottyM (Feb 2, 2020)

@John Conroy - Thanks, John! That's the plan, I'll go all out on this as it's such a good base and most likely keep for a long long time. I wish I was around when things like this were still being made. 

@Hruul - Glad you enjoy them! Try to take as many pictures as I can for those little things I might not have noticed and need to check when reassembling. This lathe does have some good manual available online though.


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## Dabbler (Feb 2, 2020)

really nice workl!!!


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## John Conroy (Feb 2, 2020)

Interesting design on the front spindle bearing. I have never seen one that used spring to control bearing preload. It makes sense when I think about it though. The bearing will maintain sufficient preload through it's entire life even after a little wear occurs.


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## Dabbler (Feb 3, 2020)

RobinHood's Colchester is the same.  A truly elegant system - with one flaw.  You cannot take deep cuts feeding away from the headstock.  this compresses the springs, and the main headstock bearings are no longer preloaded.


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## Swissmat (Jul 6, 2020)

ScottyM said:


> It's a type of toolpost that lets you change angles to repeatable positions very quickly. I've never owned one until now, now don't think I could buy a different style.



Hey Scott, 

what size is the multifix that came with your student?
thanks!


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## Bowhead (Jan 31, 2021)

I’m new to this forum and it was your lathe that caught my eye. I too have a round head that needs some love. The single phase vibration issue has reared its ugly head in my direction. I’ll take the advice of a 3 phase and VFD. Have you found a “favourite” resource or website for finding parts?

great post.


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## johnnielsen (Jan 31, 2021)

ScottyM said:


> Funny you should mention that! My cousin has a nice VDF lathe that I helped him setup the other week. The headstock is a little out though and he's got the bug to work on it again. I sense a teardown coming. Awesome machine!
> 
> View attachment 7132


Hi Scotty
I also have a VDF Boehringer lathe. It is an older 48SR (probably 1960s) with the same headstock transmission and the same powered turret I have an english language manual for the engine lathe version and a German manual that includes the powered turret. If you don't have these, I can pdf for you. I am still looking for an english language manual for the turret as I need to fix a couple of things.


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