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This is why i need to learn to use turcite and hand scrape

marka12161

Stainless
Joined
Dec 23, 2016
Location
Oswego, NY USA
Monarch 16CY tailstock. The flat bearing surface is badly scratched. The wear on one end is .022 greater than on the other.

I will be hosting one of Richard King's scraping classes in my shop in Oswego NY in May 2020. Hopefully i will learn how to correct this condition during the class.
 

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The consensus on Turcite and tailstocks is, don't do it. The Turcite is too slippery and the tailstock will slip. Instead, you need to scrape the base to the ways and then shim between the base and body. I'd be tempted to fit the base to the ways, set up some jack setscrews between the base and body, tweak into alignment, and then fill the gap with Moglice. This assumes the tenon that takes the thrust between the base and body is intact.
 
How do the matching flat- and V-ways look? You can get a crude idea of the condition by mounting a dial test indicator on the carriage then running it back and forth with the probe on the tailstock ways.
 
The consensus on Turcite and tailstocks is, don't do it. The Turcite is too slippery and the tailstock will slip. Instead, you need to scrape the base to the ways and then shim between the base and body. I'd be tempted to fit the base to the ways, set up some jack setscrews between the base and body, tweak into alignment, and then fill the gap with Moglice. This assumes the tenon that takes the thrust between the base and body is intact.

I believe that Moglive would present the same friction problems of Turcite and other materials designed to reduce friction.

Paolo
 
I believe that Moglive would present the same friction problems of Turcite and other materials designed to reduce friction.

Paolo

I think he's just suggesting filling the gap between base and body so there shouldn't be a (lack of) friction problem. Just a shortcut to getting the shims right. It assumes that parallelism is maintained, otherwise the tailstock could point towards the front or back and the only way to compensate for that is to scrape clearance into the key aligning top and bottom and getting Moglice in there as well. It just keeps getting uglier.

The more elegant solution would be to fit the base to the ways, scrape the top of the base parallel to the bottom, then use a uniform shim to bring the tailstock quill back up to center vertically.
 
I think he's just suggesting filling the gap between base and body so there shouldn't be a (lack of) friction problem. Just a shortcut to getting the shims right. It assumes that parallelism is maintained, otherwise the tailstock could point towards the front or back and the only way to compensate for that is to scrape clearance into the key aligning top and bottom and getting Moglice in there as well. It just keeps getting uglier.

The more elegant solution would be to fit the base to the ways, scrape the top of the base parallel to the bottom, then use a uniform shim to bring the tailstock quill back up to center vertically.

I agree with your last sentence but I'd machine the base down and fit a 1/4" thick plate rather than a thin shim. Fasten it down with countersunk screws.

Regards Tyrone.
 
Chances are, the tail stock quill/spindle is a very sloppy loose fit in the TS housing by now in life. With what everyone else has said, this may be a time to re-line bore the housing after the base/housing has been re-worked and shimmed. Once re-bored, honed out to a smooth finish with a cylinder hone (glaze breaker hone). Then send out the tail stock spindle to be chromed and ground to fit the new re-bored housing. Yeah, a lot of work, part of getting it right! Don't do just a half a$$ job. It probably needs it. Ken
 
One other thing you will likely hear is that you need to start by getting the bed inspected/scraped first as it will be your standard for the rest of the machine.

I'm going into my Hendey backwards (and will likely give myself trouble for it) by starting with the cross-slide. The bed is in bad shape, but I don't have the space and time presently to pull it over to swatkins plainer down the road from me, and my cross slide was barely functional (took all of 1/8" of Turkite to fix the gaulding and wear) so I started there. My only hope is to leave the overall alignment of my lathe out of the equation and just focus on the cross-slide's local alignment. I'm using some factory surfaces on the saddle for reference points that I can also use when I do get the bed fixed and the bottom of the saddle matching it. The cross slide likely won't be true to the spindle or bed right now and once the bed/saddle are fixed, I might even have to go back and touch up the cross-slide.

You might be better off leaving the bottom of the tail stock alone and shimming it up to height right now. If you fix the base, it will likely help things, but you'll need to leave room in your measurements for bed issues and don't over correct things with your tail-stock repairs.
 
You might be better off leaving the bottom of the tail stock alone and shimming it up to height right now. If you fix the base, it will likely help things, but you'll need to leave room in your measurements for bed issues and don't over correct things with your tail-stock repairs.
That's similar to what I did. I took a measurement of much would need removed to get every thing square, then rounded up to the next size shim stock. I think I needed to remove .022" but ended up taking off .025". I stated with the vee, because it's the hardest to get correct, and then went to the flat way.

Upon reassembly I trimmed out some brass shim stock, stuck her all back together and 7 years later I don't regret a thing.
 
My approach would be to scrape the tail stock to fit the ways as it. Then set it up and mill or blanchard grind the top. Then cut out a shim and grind it to thickness. If you have a squareness issue in the horizontal plane, cut for a wider key.
 
Thanks for all the input. When i separated the top and bottom castings there was some kind of paper shim in there so clearly someone tried to correct for some amount of wear. The comments on not using turcite and instead correcting with some kind of shim strategy makes all the sense in the world. My plan for the machine is to first assess the whole thing before i do anything that can't be easily reversed. I still have to remove the apron and carriage and assess those where i suspect i'll find similar wear. My goal is to use some of the scraping class time to learn how to assess the condition of the bed and other major components and come up with a plan to correct as much as i can without breaking the bank. This is a very complete machine, the headstock gears all look great and i didn't pay an outrageous price for it so i'm not opposed to devoting some time and maybe a bit of money to setting it as right as makes sense for my purposes. I am but a mere hobbyist but at some point, i wouldn't be opposed to taking on the occasional side job to fund the habit. Until the class starts up in May, i'm going to focus on getting everything clean and getting the lubrication system working properly and then take some test cuts to see how good or bad it is.
Mark
 
I would just shim it and use it. Just throw some oil on it now and then and it probably won't get any worse.

You can still turn a dead straight shaft between centers even if the tailstock is completely screwed.

You're talking about a pretty massive undertaking- a lot of time to make a worn out old machine like new and in reality it won't make a bit of difference in how it performs for you.
 
I would just shim it and use it. Just throw some oil on it now and then and it probably won't get any worse.

You can still turn a dead straight shaft between centers even if the tailstock is completely screwed.

You're talking about a pretty massive undertaking- a lot of time to make a worn out old machine like new and in reality it won't make a bit of difference in how it performs for you.


^^^ THIS ^^^

And you can buy metal, tooling, even another machine off the money NOT spent on courses, travel, and lodging.

All to rebuild what? Three machines in your lifetime that made more sense than just buying a less wore-out machine for about the same cost to begin with?
 
I don't see this as a massive project at all. I've learned that all of these old machines have issues and you don't know what you have until you take them apart and look. The fun is in figuring out what you have and determining the sweet spot for setting things as right as you can and then doing it. It won't be in like new condition but it'll be much better than it is today.
 
I don't see this as a massive project at all. I've learned that all of these old machines have issues and you don't know what you have until you take them apart and look. The fun is in figuring out what you have and determining the sweet spot for setting things as right as you can and then doing it. It won't be in like new condition but it'll be much better than it is today.

Yah well.. perhaps most of us over age 50 worked in an era when the machine-tool under our hands belonged to "the company".

Worse- during periods of history when FAR too many of those companies were living-off surplus left over from the huge build up for wars. War ONE as well as War Two, for some among us who are another quarter-century older, yet.

Worse-worse,? Most of those companies could not - or WOULD NOT - even permit us to improve our machines, even when we knew how and they didn't need much for at least modest improvement.

Now - I'm not saying "so YOU should SUFFER, too!"

Not at all. Bear with me..

Time having moved-on, Old Iron is now key to the very survival of small shops where hands now one and two generations younger have no other affordable option.

How did we manage to get on-spec parts out the door on schedule and on budget?

We, then - and I don't mean just grizzled old veterans - AND y'all younger lot NOW ...learnt to "compensate" for the shortcomings of any machine we touched.

"WE" being relative "newbies".

Walk in the door, age 18, already knowing how to get good work off bad machines. Not just "superstars". Every man jack who was punching the clock HAD to be able to deliver that, or was out the door, first 30 days, probation.

End of the day, being able to get a job done with what you HAVE, not what you WISH you had is far the more useful skill than being able to make the machine less imperfect.

Because it is not limited to machining.

It is every bit as valuable every step of the way, Machinist, USWA on hourly wage to head of a corporation.

Learn rebuilding skills? Do so if you can. Those can make you proud.

But along the way?

Learn to "run what you got and whine ye not".

That can make you safer in parlous times, if not also happier, wealthier, and wiser, all the time.

In all things. Blanket-sharing included.

Bedrooms are the LAST place scraping anything flat and flaking it for oil-retention is wanted, whether blued, screwed, or simply tattoo'ed!

:D
 
My approach would be to scrape the tail stock to fit the ways as it. Then set it up and mill or blanchard grind the top. Then cut out a shim and grind it to thickness. If you have a squareness issue in the horizontal plane, cut for a wider key.

Do you mean to achieve alignment via working over the top of the TS base?
 
That's a great demonstration project for the class! I think Turcite might not be the best choice since it's slightly compressible, which will make getting the tailstock back to center height more of a iteration than a measurement. I would scrape the worn surface flat again and parallel to the top surface that the rest of the tailstock bolts to. Then I would measure how low you are from the headstock centerline and make some shims to go between the two parts.
You can use the same measuring set up you have now for the inverted V by dropping a gauge pin in there. Broken carbide endmill shanks work well if you don't have a big enough pin handy.
Richard will have a bunch of advise and will probably also offer to take you camping!
Hahn Rossman
 
Do you mean to achieve alignment via working over the top of the TS base?

The tailstock has to be inline with the spindle centerline in two planes. You are worrying about the vertical plane, the front of the tailstock being low. But, remember that the tailstock also has to be in line left to right. That's controlled by the ways and a key between the top and bottom half.

I ran into an issue on a CNC lathe once that would not repeat on tailstock jobs because that key had been machined out of square. So, if the tailstock was sticking out further or less than where it was when it was centered to the spindle, the parts would be big or small at the tailstock end.
 
I don't see this as a massive project at all. I've learned that all of these old machines have issues and you don't know what you have until you take them apart and look. The fun is in figuring out what you have and determining the sweet spot for setting things as right as you can and then doing it. It won't be in like new condition but it'll be much better than it is today.

I see it differently. I see it as any lathe that has that much worn off the bottom of the tailstock is not worth one iota of anyones time to try making it nice. The rest of the machine is probably worse. So with that in mind and the reality that you probably aren't going to grind or plane the ways anyway why would you bother with the tailstock?

I have gone down this road and I have learned you are just infinitely better off to buy a machine in good shape if that's what you need. And again, 99.99% of the work you could do on that lathe will not care how knackered the tailstock is. The tailstock is adjustable and shimmable and you can even twist the bed around if you need to.

Going into the tailstock deal you will have to establish some kind of reference and make everything good off of that. I bet you nothing is good enough to be a reference and anything you do will be a compromise.

If you level up the bed sorta well and shim up the tailstock to get the height close and line up the tailstock side-side you should be able to make pretty much anything on that machine without any problems and do it by noon tomorrow.

If you tear it apart it will be a mess for how long? A few weeks? 6 months? 5 years?
 
The great thing about this board is the diversity of viewpoints. All points of view are valid and, as they say, where you sit is where you stand. As i mentioned above, I'm a hobbyist and I have the luxury of time. I'm also more than a little bit of a nerd and i really enjoy the challenge of working through problems like this. I agree i could probably go out and find something in better condition and just use it right away but where's the fun in that? I suspect that at the end of the day, i'll end up living with the bed ways as they are and scraping in the carriage & cross slide and scraping and shimming the tailstock.
 








 
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