Darren's active projects

[Mcgyver]

I spent a bit of time tonight measuring for wear on the lathe bed, and I'm pretty happy so far. Its still on the trailer, and needs a good cleaning but my 1/2 thou mitutoyo indicator showed maybe 2 or 3 tenths up close to the headstock on the front v way, and maybe 1/2 thou on the rear flat way and about the same for the tailstock ways

Nice.

There is an oil pump in the apron with lines going to the carriage bed and cross slide ways. If everything is working, the sliding surface stays lubricated and they last indefinitely.

....but..... after decades and decades the small copper tubes deliverying the oil very often get clogged. 'Then the lathes gets used for decades without the lube system working on one or more ways. They are a bit of a pain to fix/replace, they're on the underside of the carriage, but you want to have them working.

 

[Darren]

Thanks for that info. I haven't dug into it yet and did not know that it was oil fed. I will have to get the manual for it.

I did notice that the bearings under the carriage are out of adjustment and need to be replaced or repacked.

The gentleman who I bought the machine from was a tool and die maker, turned full-time farmer. He owned it for 20 years, so hopefully he took care of it.

 

[Susquatch]

It was the best they had at the time for variable speed with full torque available from near zero rpm to 4000rpm.

This comment is dead nuts on the money. It recognizes the importance of maintaining torque.

HP and Torque seem to get confused. Constant torque does you little good - you want torque to go up as speed goes down to maintain constant HP.

Darren's active projects

Thanks everyone

canadianhobbymetalworkers.com

I've thought about a reply to all your points for several days now. On reflection I believe that it isn't productive to erode this thread with yet another exhaustive debate on this subject. I love what @dfloen is doing with his lathe and I really don't want to detract from that here. Therefore I'd prefer to refrain from exhaustively addressing each of your points. I'd rather just agree to disagree on the substantive issue for now. In summary, my view is that your points show that a bigger machine is better. To me, that's a no brainer. But getting a bigger machine with more hp isn't that simple for some of us. Therefore, a VFD is an affordable way to significantly expand the capabilities of an existing piece of equipment. To crystallize our difference of opinion, allow me to use a play on your words to reflect my point of view. Basically, I believe that: "The constant torque that a VFD provides as the speed goes down is very valuable. The corresponding loss in hp does little harm."

In the interests of resolving our differences of opinion to our mutual benefit and that of others who are interested, may I suggest that you or I create a new thread dedicated to this subject so we can take the time to debate it to our hearts content without further hi-jacking this thread. If you agree to do that, I'll address the points in your reply more completely there.

I think there are also some obvious other advantages to doing a separate thread. It could provide a good reference for others in the future, and making it a formal focussed debate facilitates a more collegial approach without time or space constraints. I've never done that before, but it seems like a better way to beat the horse to death than upsetting those who are not interested. Perhaps it could also serve as a model for debating other issues too - or perhaps a darn good reason not to! LOL!

 

[Darren]

I welcome all discussion in this thread.

The math is simple. Torque must go up as RPM decreases to maintain HP, if that is your goal. The reverse is true if RPM rises, torque must decrease to maintain constant HP. Again, the math is simple. Perhaps it is the goal that isn't. Torque is the power to twist. HP is how much work can be done in a time period. I tend to think in terms of torque when i'm visualizing gearing and powering a machine with the various options.

 

[Darren]

So, i have a dead truck on one hoist, a dead BMW on the other with elecrical issues. My Bobcat has a frozen battery. The lathe is half under the BMW, on the trailer. The BMW weighs 3500, the lathe weighs 3000-3500, the hoist is rated for 10k. I think I can sling the lathe to the hoist arms using some spreaders to present a vertical only load to the hoist, instead of trying to pull the arms sideways, and balanced between the 4 arms. So hopefully the hoist can lift the lathe and the bmw at the same time so i can get the trailer out and the pallet jack under the lathe. Should be fun.

 

[Susquatch]

I welcome all discussion in this thread.

The math is simple. Torque must go up as RPM decreases to maintain HP, if that is your goal. The reverse is true if RPM rises, torque must decrease to maintain constant HP. Again, the math is simple. Perhaps it is the goal that isn't. Torque is the power to twist. HP is how much work can be done in a time period. I tend to think in terms of torque when i'm visualizing gearing and powering a machine with the various options.

Agreed 100%. I think in terms of torque too not HP. My career was in the auto industry. The sales and marketing guys and the writers all wanted hp so we gave it to them. But in the lab we talked torque not hp.

When I got my vfd rated motor from emotors, the sales engineer told me that customers only ask about hp but the techs only cared about torque. Therefore I believe it was the same way in the electric motor industry.

HP sells.

As you say, the math is simple.

Bottom line - I LOVE my VFD and VFD rated motor. I don't worry about the HP loss as the speed goes down. The torque keeps right on cutting.

 

[YYCHM]

My Bobcat has a frozen battery.

Frozen battery? You're sitting at a balmy -12C. I don't plug in until it's -20C or colder.

 

[Susquatch]

So, i have a dead truck on one hoist, a dead BMW on the other with elecrical issues. My Bobcat has a frozen battery. The lathe is half under the BMW, on the trailer. The BMW weighs 3500, the lathe weighs 3000-3500, the hoist is rated for 10k. I think I can sling the lathe to the hoist arms using some spreaders to present a vertical only load to the hoist, instead of trying to pull the arms sideways, and balanced between the 4 arms. So hopefully the hoist can lift the lathe and the bmw at the same time so i can get the trailer out and the pallet jack under the lathe. Should be fun.

Now that's what I call a problem. Without being there to see it first hand, I'd be terrified of rendering an opinion. Sounds like a call to @Brent H might be in order. Last I heard he was in Lake Superior headed to TBay.

 

[Darren]

Lol it's been dying for a year or so. It's not an easy job to change it now that it's buried in snow and the battery is covered in frozen mud. Ill have to get at it though.

In the meantime. I need to get the lathe off the trailer, get the trailer out of the shop, so I can fix the BMW and get it out of my life.

 

[Darren]

Now that's what I call a problem. Without being there to see it first hand, I'd be terrified of rendering an opinion. Sounds like a call to @Brent H might be in order. Last I heard he was in Lake Superior headed to TBay.

it won't be a problem. I have a plan. I'll post some pics in the morning

Brent was in town yesterday. Met up with him on my way out to grab lunch.

 

[Susquatch]

it won't be a problem. I have a plan. I'll post some pics in the morning

Brent was in town yesterday. Met up with him on my way out to grab lunch.

Did Brent see the situation there?

Glad you have a plan. That's better than NO CLUE.

 

[YYCHM]

Did Brent see the situation there?

Glad you have a plan. That's better than NO CLUE.

I think @Brent H is on the move now? Next POC?

 

[Dusty]

So, i have a dead truck on one hoist, a dead BMW on the other with elecrical issues. My Bobcat has a frozen battery. The lathe is half under the BMW, on the trailer. The BMW weighs 3500, the lathe weighs 3000-3500, the hoist is rated for 10k. I think I can sling the lathe to the hoist arms using some spreaders to present a vertical only load to the hoist, instead of trying to pull the arms sideways, and balanced between the 4 arms. So hopefully the hoist can lift the lathe and the bmw at the same time so i can get the trailer out and the pallet jack under the lathe. Should be fun.

Play it extremely safe whatever you do because we need you.

 

[Dusty]

I think @Brent H is on the move now? Next POC.

Tried tracking the Samuel Risley using this, no luck can't find the vessel.

Marine Traffic | Marine Vessel Finder

Marine Traffic AIS Tracking World Map

www.marinevesseltraffic.com

 

[YYCHM]

Tried tracking the Samuel Risley using this, no luck can't find the vessel.

Marine Traffic | Marine Vessel Finder

Marine Traffic AIS Tracking World Map

www.marinevesseltraffic.com

Canadian Coast Guard are Ninga Steath guys LOL.... OR ......... move so slowly they can't be tracked....

 

[Susquatch]

Tried tracking the Samuel Risley using this, no luck can't find the vessel.

Marine Traffic | Marine Vessel Finder

Marine Traffic AIS Tracking World Map

www.marinevesseltraffic.com

Here it is.

Ship SAMUEL RISLEY (Buoy-Laying Vessel) Registered in Canada - Vessel details, Current position and Voyage information - IMO 8322442, MMSI 316001890, Call sign CG2960

Vessel SAMUEL RISLEY is a Buoy-Laying Vessel, Registered in Canada. Discover the vessel's particulars, including capacity, machinery, photos and ownership. Get the details of the current Voyage of SAMUEL RISLEY including Position, Port Calls, Destination, ETA and Distance travelled - IMO...

www.marinetraffic.com

 

[Susquatch]

Wow. I found him with a simple google search but a second try failed. I ended up creating an account on vessel finder, but it shows him still in TBay.

I think you guys are right. Stealth mode has been activated.....

 

[Mcgyver]

I confess I do not understand this conversation. You suggest I'm wrong (since all I'm proffering is the formula, ergo that the formula is wrong) then say you agree with the formula and that the math is simple, and then say loss in HP does little harm.

"The constant torque that a VFD provides as the speed goes down is very valuable. The corresponding loss in hp does little harm."

That is not true for machine tools. With a machine tool, you reduce speed because the diameter is larger. If the diameter is larger the torque must increase to do the same work (DOC and feed at the same SFM, i.e. removal rate).

Its nothing to do with a bigger machine being better, nor did I suggest that. Read through the two examples I gave. Speed goes down because the work piece is 6x the diameter. So you run it at 1/6 of the speed. If you want to take the same DOC and feed rate, so you end up with the same removal rate, in a work piece 6x the diameter, you need 6x the torque. This is why mechanical speed reduction or the 10ee MG drive will give better performance than will a VFD.

The only scenario where constant torque and falling horsepower would make no difference, would be if only speed were changed while the diameter, DOC and feed was not changed....but that criteria sidesteps the fundamental reason for a wide range of speeds on machine tools - working with different diameters.

I've been wrong many times before and will many times again, .....however this is basic physics formulas not an opinion or a debate. If you are not disputing the formula, where and how can what I posted be wrong?

 

[Brent H]

We are still here in T-Bay for the foreseeable future until H E - Double Hockey Sticks freezes over - so to speak. No ice to break (which is a good thing right now) and lets just say - I am the last man standing in the ER so I can't leave the ship or visit @ShawnR or @dfloen - which sucks. It will be a very subdued New Years and that's about all I can say about that.....

I wish you luck @dfloen and would be there in a heart beat to lift that f.....sucker with you if I had the choice!

Today is project day and I will try and get some posts out on some Miss Metric repairs and I am currently fabbing up a cam bearing extractor/insert tool for the car project

Stay healthy out there folks!!!

 

[Susquatch]

I confess I do not understand this conversation. You suggest I'm wrong (since all I'm proffering is the formula, ergo that the formula is wrong) then say you agree with the formula and that the math is simple, and then say loss is HP does little harm.



That is not true for machine tools. With a machine tool, you reduce speed because the diameter is larger. If the diameter is larger the torque must increase to do the same work (DOC and feed).

Its nothing to do with a bigger machine being better, nor did I suggest that. Read through the two examples I gave. Speed goes down because the work piece is 6x the diameter. So you run it at 1/6 of the speed. If you want to take the same DOC and feed rate, so you end up with the same removal rate, in a work piece 6x the diameter, you need 6x the torque. This is why mechanical speed reduction or the 10ee MG drive will give better performance than will a VFD.

The only scenario where constant torque and falling horsepower would make no difference, would be if only speed were changed while the diameter, DOC and feed was not changed....but that criteria sidesteps the fundamental reason for a wide range of speeds on machine tools - working with different diameters.

I've been wrong many times before and will many times again, .....however this is basic physics formulas not an opinion or a debate. If you are not disputing the formula, where and how can what I posted be wrong?

Since the OP welcomes the debate here, I'll engage.

My objection is simple. You are almost always correct in what you say. But you consistently say it in a way that insults the VFD and sings the praises of a bigger machine. And I consistently get my knickers into a knot over it! Hp alone is not the holy grail. Again, within limits there are other ways to skin the cat.

The VFD is not a fake improvement. Within limits, they do work. And they are a gift to those of us who can't have the bigger machine. See my response to Tom Kitta above. He did a great job of describing the difference but didn't knock the VFD in the process.

I'm guessing you are not doing this on purpose. I admire most of your responses elsewhere on the forum. Your knowledge and experience runs very deep. My guess is that this is a little like that time you told your buddies wife (let's call her HP) how beautiful she is (and she really is), but now your wife (let's call her Torque) who is beautiful in her own right, is pissed off at you. I doubt you do it on purpose, but I did take offense to it and felt obligated to take you to task over it.