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Jim2
01-12-2010, 09:01 PM
I've got an old Leblond lathe. It's a 1924, 15" Heavy Duty. The tailstock is pretty worn. The internal taper surface is grooved, but it still holds. It doesn't line up perfect when I'm drilling holes, but I can still get it to drill pretty well using the right technique.

The big problem that I have is that the bore seems to be worn oversize. I have a very difficult time tightening the ram enough to hold when I'm using a center. I actually switched the short lever that was originally used to lock the ram with one of the large nuts that was used to lock the body of the tailstock to the ways. Now I can use the large wrench to tighten the ram in the tailstock, but it is still very difficult to get it to lock.

I took some measurements, and the ram seems to be around 1.997"-1.999" all the way along it's length. The bore seems to be around 2.005" to 2.007" at the mouth. I didn't try to take measurements further inside the bore. All measurements were taken with telescoping gauge measured w/ my HF digital calipers, if that matters.

I'm wondering if anyone else has reworked their tailstock? Would you just make an oversize ram and hope for the best? Is it possible (easy) to re-bore the tailstock?

If i was to make another ram i would make it a little longer so that I could easily attach a Chicom scale to measure holes while drilling. . . .

Here's a shot of the tailstock
http://img.photobucket.com/albums/v280/jasch/Leblond/Tailstock/02-Tailstock.jpg

more pics at http://smg.photobucket.com/albums/v280/jasch/Leblond/Tailstock/

Jim

Tinkerer
01-13-2010, 12:26 AM
Jim I would start by taking the ram out and looking at the cotter... I'll bet it's in need of replacing if you can't get a good lock down on the ram. Then I would clean the split on the back side of the tailstock remove the years of gunk it's most likely accumulated... then adjust it with the ram placed back. After that get a morse reamer and clean up the socket. And see what type of difference that makes before moving to boring it for a new end piece.

rklopp
01-13-2010, 12:28 AM
On my Monarch 10EE, I had the tailstock bore honed to round and straight, and then turned up a new ram using the 10EE (and my other lathe when I needed center support or drilling capability). I lapped the ram to a very close fit with the honed bore. I had to re-machine and lightly scraped the tailstock base and shim the body to restore the center height. It came out great. If you go this route, clamp a shim in the split so the bore stays round during honing or machining. My tailstock has a split cotter instead of a split in the casting.

Jim2
01-13-2010, 09:50 AM
Jim I would start by taking the ram out and looking at the cotter... I'll bet it's in need of replacing if you can't get a good lock down on the ram. Then I would clean the split on the back side of the tailstock remove the years of gunk it's most likely accumulated... then adjust it with the ram placed back. After that get a morse reamer and clean up the socket. And see what type of difference that makes before moving to boring it for a new end piece.

I don't think there's a split cotter in there. I think the ram locks by clamping the split in the tailstock casting. I guess I should look at it a little closer to be sure, though.




On my Monarch 10EE, I had the tailstock bore honed to round and straight, and then turned up a new ram using the 10EE (and my other lathe when I needed center support or drilling capability). I lapped the ram to a very close fit with the honed bore. I had to re-machine and lightly scraped the tailstock base and shim the body to restore the center height. It came out great. If you go this route, clamp a shim in the split so the bore stays round during honing or machining. My tailstock has a split cotter instead of a split in the casting.


Why did you have to re-machine the tailstock base? Was that to get enough clearance for a shim or maybe because it was worn more on one end or something?

At this point, I should probably 'fess up and say I'm a little out of my depth here. I don't have this lathe leveled out the "right" way, or at all for that matter. I would think that it would be a good idea to have the ways sitting straight and true before setting up to re-bore the tailstock, right? I don't have a precision level. I'm really not sure the floor in my shop is very solid either. Whoever did the concrete here definitely tried to get by on the cheap. I think the slab is quite thin and it feels like it moves (or vibrates) when my air compressor comes on. So, all kinds of excuses there, I know!

Anyway. . . . There's a class starting at the tech college here. I've been thinking about taking it. It's kind of a drive for me, and gettting there on time will be a hassle. I'd have to leave work early, and miss dinner (I don't like missing meals!). Maybe that would help me meet some local folks that might be able to share some expertise?

Really, I can get along with the way it is, but if there was some minimal improvement that could be made w/o wrecking anything--that would be good! Adding a digital scale for monitoring the depth I'm drilling would be really nice, too.

Jim

Fasttrack
01-13-2010, 11:03 AM
Hey Jim, where are you located? There may be more people "local" then you think!

I've seen several threads here regarding refurbishing tailstocks. One even involved nitriding the ram, IIRC. You might see what a search turns up.

Jim2
01-13-2010, 06:30 PM
You're right, Fasttrack. Searching on tailstock turns up lots of stuff. I had been doing a simple search, but that gave to much stuff to wade through. When I did an advanced search with "tailstock" in the title only, I got some good info.

I updated my profile to give my location. I'm in Wisconsin.

Jim

Fasttrack
01-13-2010, 08:51 PM
Well, I'm not promising anything, but I might be headed up to WI at some point later in the spring to pick up a clapper box. If I do, I'll let you know and I will bring along a master precision level (I'm a proud new owner of a used no. 199 ;) ). You'd be welcome to borrow it.

Mcgyver
01-14-2010, 01:51 PM
On my Monarch 10EE, I had the tailstock bore honed to round and straight, and then turned up a new ram using the 10EE (and my other lathe when I needed center support or drilling capability). I lapped the ram to a very close fit with the honed bore. I had to re-machine and lightly scraped the tailstock base and shim the body to restore the center height. It came out great. If you go this route, clamp a shim in the split so the bore stays round during honing or machining. My tailstock has a split cotter instead of a split in the casting.

Russ, I think read your account of this; sending the tailstock out for honing and them holding the casting by hand while using a sunnen honing machine etc ---was that yours?

I'm looking at a similar repair and wonder if line boring and then honing the tailstock all done on the lathe would work and if that occurred to you. I'm thinking pressing a bearing on a bar and holding it in the steady rest. I know its a lot overhang on the line boring bar, but the affect of that is tied to depth of cut, with enough patience the bore should come out perfectly (if set up properly) parallel the tailstocks V way and the lathe's axis....that's why just honing the bore concerns me - what keeps in aligned?

.RC.
01-14-2010, 04:05 PM
http://www.practicalmachinist.com/vb/showthread.php/fit-t-s-ram-158423.html

Jim2
01-14-2010, 10:44 PM
Thanks for the link to that thread on PM. Very interesting. That is kind of what i was thinking of doing. . . well the boring part anyway. The honing is beyond me. Towards the end of the thread there were some posts that suggested that accuracy could be relaxed a bit for a lathe that is somewhat worn. I think my Leblond matches that description pretty well. I'd be more likely to try what you've got in mind there, Mcgyver.

Fasttrack, thanks for the offer of the precision level. I need to study up on that a bit before I'd be able to try that. There are more or less 6 feet on this lathe as the headstock end is supported in 4 spots. I've always figured that would make leveling it out a little more complicated.

I don't know as this lathe really requires the nth degree of accuracy or precision anyway. I enjoy making swarf as much as the next guy, but I don't even own anything that measures to tenths. My HF digital caliper gets me as close as I need to be on everything I've done so far. As I understand it, accuracy really doesn't exist without surface finish, and this old lathe only turns 350rpm at its highest speed. Unless I'm making something 4" or more in diameter, I probably don't have the surface speed to get the finish anyway, right? Besides that, the straight-cut gears on the headstock have a tendency to cause some interesting patterns in the work.

OTOH, there was a comment on that link about having drills w/ broken lips if you don't get the ram (er, quill!), tight in its bore. I've actually thought of starting a thread to ask why so many of my drills have a broken lip. . . . So, I guess I got my answer.

Lots of stuff to think about. . . . Now back to the search to find some help on leveling out the ol' girl.

Jim

Mcgyver
01-14-2010, 11:03 PM
don't be too quick to discount the honing, or to be more descriptive of what i was thinking, lapping. I've not lapped a tailstock barrel, but have done lots of engine cylinders and its not too difficult. I'm guessing the greatest challenge is make sure the outboard support (likely a steady) is absolutely spot in centred to the spindle axis. Here's some pics of some simple home made laps, I was thinking something like these adjustable laps following boring and then grinding or lapping a new barrel as Russ suggests. mines a 10ee as well so if i ever get to it want to make the big effort get it near perfect.....hey if we always try to get it perfect then quite often it'll be good enough, right? Was in Madison last fall, nice town.


http://i20.photobucket.com/albums/b201/michael0100/lapping/collectionoflaps-1.jpg

http://i20.photobucket.com/albums/b201/michael0100/lapping/afteruse.jpg


they're brazed on one side so that can expand:

http://i20.photobucket.com/albums/b201/michael0100/lapping/lapcloseup.jpg

oldtiffie
01-14-2010, 11:40 PM
I've got an old Leblond lathe. It's a 1924, 15" Heavy Duty. The tailstock is pretty worn. The internal taper surface is grooved, but it still holds. It doesn't line up perfect when I'm drilling holes, but I can still get it to drill pretty well using the right technique.

The big problem that I have is that the bore seems to be worn oversize. I have a very difficult time tightening the ram enough to hold when I'm using a center. I actually switched the short lever that was originally used to lock the ram with one of the large nuts that was used to lock the body of the tailstock to the ways. Now I can use the large wrench to tighten the ram in the tailstock, but it is still very difficult to get it to lock.

I took some measurements, and the ram seems to be around 1.997"-1.999" all the way along it's length. The bore seems to be around 2.005" to 2.007" at the mouth. I didn't try to take measurements further inside the bore. All measurements were taken with telescoping gauge measured w/ my HF digital calipers, if that matters.

I'm wondering if anyone else has reworked their tailstock? Would you just make an oversize ram and hope for the best? Is it possible (easy) to re-bore the tailstock?

If i was to make another ram i would make it a little longer so that I could easily attach a Chicom scale to measure holes while drilling. . . .

Here's a shot of the tailstock
http://img.photobucket.com/albums/v280/jasch/Leblond/Tailstock/02-Tailstock.jpg

more pics at http://smg.photobucket.com/albums/v280/jasch/Leblond/Tailstock/

Jim

Jim,

as I read it, you have 0.006">0.010" clearance between your tail-stock and the quill and just want to do the minimum necessary to reduce the gap and increase the clamping efficiency so that you can back to "as was" and machining with least time, effort, disruption and cost.

Why not just fit a 0.003">0.005" strip of brass shim as a lose-fitting "sleeve" that wraps around between the tail-stock and the quill. Fit two "tabs" or "ears" on it an drill them to suit the quill clamping bold (the tabs/ears fit in the slot that the quill clamp squeezes closed to clamp the quill.

Sometimes some of these "shade-tree", "hill-billy" or "red-neck" methods have their uses. I did stop short of fencing wire and the "Big F*ckin* Hammer" though - even if only just!!

Some jobs are unnecessarily "over-thunk" and "over-wurried" about.

Jim2
01-15-2010, 09:15 AM
Jim,

as I read it, you have 0.006">0.010" clearance between your tail-stock and the quill and just want to do the minimum necessary to reduce the gap and increase the clamping efficiency so that you can back to "as was" and machining with least time, effort, disruption and cost.


Yes, that is exactly what I'm looking for.




Why not just fit a 0.003">0.005" strip of brass shim as a lose-fitting "sleeve" that wraps around between the tail-stock and the quill. Fit two "tabs" or "ears" on it an drill them to suit the quill clamping bold (the tabs/ears fit in the slot that the quill clamp squeezes closed to clamp the quill.


I think that sounds like the best idea yet! I could always go to the next level when time, experience, conditions warrant. Nothing would be harmed. . . . I like it! Thanks, Tiff.

I'll have to look into some shim stock from McMaster-Carr.

Jim

Jim2
01-15-2010, 09:18 AM
Mcgyver, thanks for posting pics of those laps. I've not seen anything like it. Those look like they'd work great.

Jim

J Tiers
01-15-2010, 09:21 AM
The shim idea is OK if the wear is on the cast iron. You implied it was on the bore, but you don't seem totally certain. It may be on, or partly on, the quill (it is on mine), which measuring will show, in which case shimming isn't really an option, unless you use removable shims that you use as and when needed.

Like the legend of the guy who had a whole box of them to use in special cases on teh machine he ran, and his replacement couldn't get the machine to work accurately because "old Bob" hadn't showed him the secret of which to use where in what cases......

Jim2
01-15-2010, 10:38 AM
Well, I think there is so much wear that it probably is going to help no matter where it is!

I was pretty surprised that there was only a variation of .001" - .002" over the whole length of the quill. I didn't think that was very much--at least not I started reading that thread on the other site where everyone is chasing tenths, anyway. I'll take a few more measurements before I decide how thick the shims should be.

One concern that I have is that maybe the tailstock is a little low, gravity being what it is and all. The slop that is in the quill now allows the drill to find center if I let it. Once the quill is fixed in position with shims, I may be that the drill will need to flex? Probably a couple thousandths one way or the other will be no big deal. The shims are quickly reversible if it doesn't seem to work as I'd like.

Jim

Fasttrack
01-15-2010, 11:28 AM
Well, I think there is so much wear that it probably is going to help no matter where it is!

I was pretty surprised that there was only a variation of .001" - .002" over the whole length of the quill. I didn't think that was very much--at least not I started reading that thread on the other site where everyone is chasing tenths, anyway. I'll take a few more measurements before I decide how thick the shims should be.

One concern that I have is that maybe the tailstock is a little low, gravity being what it is and all. The slop that is in the quill now allows the drill to find center if I let it. Once the quill is fixed in position with shims, I may be that the drill will need to flex? Probably a couple thousandths one way or the other will be no big deal. The shims are quickly reversible if it doesn't seem to work as I'd like.

Jim


On old lathes, I've found that one of the areas of highest wear seems to be the tailstock ways about mid length of the lathe. They are as bad or worse than the carriage ways near the chuck. I suspect this is because the heavy tailstock is often pushed over dirty ways that have not been lubricated. They see a lot of wear and tear, if you think about it. No lubrication from under the tailstock (unless you've got a late-model Pacemaker, for instance) and no wipers on the tailstock means it is easy for grit/rust/CI dust/swarf to get trapped under the tailstock and act as a lapping compound.

The point is, that drop you mention could be from wear in the tailstock ways. One way to combat this is to put a shim between the base and the tailstock (there is the "base" which rides along the ways and then the rest of the tailstock - this allows the tailstock to be "set-over" when turning tapers). Unfortunately, this shim will only bring your tailstock to the correct height at one point along the ways. But you may be able to find a good "average" so that you are +/- 0.002 over the entire lenght instead of +/- 0.004 for instance.

Jim2
01-15-2010, 05:34 PM
On old lathes, I've found that one of the areas of highest wear seems to be the tailstock ways about mid length of the lathe. They are as bad or worse than the carriage ways near the chuck. I suspect this is because the heavy tailstock is often pushed over dirty ways that have not been lubricated. They see a lot of wear and tear, if you think about it. No lubrication from under the tailstock (unless you've got a late-model Pacemaker, for instance) and no wipers on the tailstock means it is easy for grit/rust/CI dust/swarf to get trapped under the tailstock and act as a lapping compound.

The point is, that drop you mention could be from wear in the tailstock ways. One way to combat this is to put a shim between the base and the tailstock (there is the "base" which rides along the ways and then the rest of the tailstock - this allows the tailstock to be "set-over" when turning tapers). Unfortunately, this shim will only bring your tailstock to the correct height at one point along the ways. But you may be able to find a good "average" so that you are +/- 0.002 over the entire lenght instead of +/- 0.004 for instance.

Well you know, I haven't tried to quantify the drop at all. Maybe a little extra shim stock would have its uses around here, though. No doubt about that!

I really don't have much experience to draw from. My dad has an ol' conehead Putnam lathe. I think it's about a 18" x 96" machine. That's been abused worse than this Leblond I would say. It is coated in an oily, gooey mess that probably is closer to lapping compound than lube. It doesn't get much use anyway. Dad takes real light cuts on it because if he takes a heavy cut it'll lift that big chuck he has on there and break bits or chatter or generally mess things up.

When I was in highschool we had some a 13" Southbend, and a couple of smaller Southbends--probably Heavy 10s I'd guess. I remember taking a cut and having a taper of .004" along the length of say 4"-5". I can't say if maybe the tailstock wasn't centered right or if maybe they were just that worn. . . . The instructor was a welder at heart, and really didn't have much love for the lathes.

Say there was a big ol' Hendey shaper up here in Whitewater for sale on Ebay a couple of weeks ago. That'd look nice next to those big lathes of yours. The guy couldn't get a bid at $200. It was such a big outfit and had a bunch of nasty looking flat-belts that looked like they'd tear your arms off. The motor was a 2hp, 3-phase, which would be another problem for me. Tempted though I was, I figure there must be a little more civilized machine out there somewhere for me.

Jim

Fasttrack
01-15-2010, 06:05 PM
Say there was a big ol' Hendey shaper up here in Whitewater for sale on Ebay a couple of weeks ago. That'd look nice next to those big lathes of yours. The guy couldn't get a bid at $200. It was such a big outfit and had a bunch of nasty looking flat-belts that looked like they'd tear your arms off. The motor was a 2hp, 3-phase, which would be another problem for me. Tempted though I was, I figure there must be a little more civilized machine out there somewhere for me.

Jim

Aww man ... now why'd you tell me that? I'm already thinking I could find a place for another monster shaper - especially for scrap price! :)

Good luck with the LeBlond. I don't what help I can be, but let me know if I can do anything. Like I said in another thread, my first "love" was a LeBlond lathe. I didn't even get to run it, but it left a lasting impression. It was the first real lathe I saw in person ;) :D

vpt
01-15-2010, 06:59 PM
I was watching that shaper as well! But damn that thing was huge and those belts looked like man killers!

oldtiffie
01-15-2010, 08:20 PM
I've got an old Leblond lathe. It's a 1924, 15" Heavy Duty. The tailstock is pretty worn. The internal taper surface is grooved, but it still holds. It doesn't line up perfect when I'm drilling holes, but I can still get it to drill pretty well using the right technique.
The big problem that I have is that the bore seems to be worn oversize. I have a very difficult time tightening the ram enough to hold when I'm using a center. I actually switched the short lever that was originally used to lock the ram with one of the large nuts that was used to lock the body of the tailstock to the ways. Now I can use the large wrench to tighten the ram in the tailstock, but it is still very difficult to get it to lock.

I took some measurements, and the ram seems to be around 1.997"-1.999" all the way along it's length. The bore seems to be around 2.005" to 2.007" at the mouth. I didn't try to take measurements further inside the bore. All measurements were taken with telescoping gauge measured w/ my HF digital calipers, if that matters.

I'm wondering if anyone else has reworked their tailstock? Would you just make an oversize ram and hope for the best? Is it possible (easy) to re-bore the tailstock?

If i was to make another ram i would make it a little longer so that I could easily attach a Chicom scale to measure holes while drilling. . . .

Here's a shot of the tailstock
http://img.photobucket.com/albums/v280/jasch/Leblond/Tailstock/02-Tailstock.jpg

more pics at http://smg.photobucket.com/albums/v280/jasch/Leblond/Tailstock/

Jim

Jim,
you've got the right attitude.

If it works well enough for you and you are satisfied - then despite the advice of any others - me included - you can do or not do just as you like when you like.

If a lathe tail-stock and quill really needed to be as good as some seem to believe it should for drilling, it would have a quill and spindle more like a good vertical mill than it would have been as the ones that are on lathes are more like a spindle and quill combination in a pedestal drill.

You have discovered one of the real truths about drilling in a lathe tail-stock. A drill going into a spinning work-piece will pretty well self-centre if left to its own devices - sometimes with a bit of encouragement - as you seem to do. Just "peck" with the centre drill - with the quill as far out as you can get it - and bingo - hole started. Support the drill chuck - in your hand - until the centre drill "pilot" is well in and the 60 degree taper cutters have started to "bite" and than you can almost go back to just winding the quill in and out of the tail-stock. If you start off with a drill just a bit bigger than the "core" of your larger drill/s the larger drills will pretty well centre themselves and need no more support once the outer diameter of the drill has centred the job.

I do pretty much what you are doing - always have. I extended the centre drill right out of the chuck and have the quill a long way out as well and just let them "float". They will self-centre most times on their own - sometimes with a bit of help.

If that lathe of yours were mine I'd leave it until it really needs doing as if you are satisfied now - why bother?

I see a lot here with "super dooper" tail-stocks and quills etc. and then they put a drill chuck - that can have a "new" run-out 0.003" tolerance (and probably more) from all the work (bashing??) its had with the quill not extended at all - and they wonder why centre-drills break and drills "play-up".

Just watch this video.

http://www.youtube.com/watch?v=bh4L65V1SqQ

and these with well-sharpened high-speed drills on "flat stuff"

http://www.youtube.com/watch?v=px9aFIabB6c

http://www.youtube.com/watch?v=3F0t2LjdyVU&feature=related

Some here won't believe it - but I've done it before. I can do it with a small drill that is hand-held using only a pin vice. It can be done with the work held in a common power drill held in a vice - no tail-stock and no lathe either.

Some here might get all excited if they had that pecker in their hands and gave it a good work-out - then they can get back to the lathe - perhaps.

The place where location and centre-height IS important is on the capstan on a capstan or turret lathe and a high-speed machining station - but "pecking" will work there too.

Some never "get it" as regards why a centre or any drill will self-centre in a lathe but will "wander" on a drill or mill when drilling into a flat surface.

That is why I like "marking out" and centre-punching followed by a "spotting" drill and then a "pilot" before I use the larger drills - both on a pedestal drill and a mill. Works pretty good most times.

I suggest that you open a beer or four, scoff 'em under that shade tree and use the can as shim in the lathe. Do the job - then back to relaxing under that big shady tree and let the others talk and worry themselves $hit-less.

Its your lathe and your call.

Have a few more cans for me too - I'd love to - but for a variety of (I think) "good reasons" I'm best staying off the "slops".

Best of luck.

Jim2
01-15-2010, 11:11 PM
Aww man ... now why'd you tell me that? I'm already thinking I could find a place for another monster shaper - especially for scrap price!

Good luck with the LeBlond. I don't what help I can be, but let me know if I can do anything. Like I said in another thread, my first "love" was a LeBlond lathe. I didn't even get to run it, but it left a lasting impression. It was the first real lathe I saw in person

You got it bad don't you? ;)

What sort of Leblond did you see? Newer than mine, no doubt?



You have discovered one of the real truths about drilling in a lathe tail-stock. A drill going into a spinning work-piece will pretty well self-centre if left to its own devices - sometimes with a bit of encouragement - as you seem to do. Just "peck" with the centre drill - with the quill as far out as you can get it - and bingo - hole started. Support the drill chuck - in your hand - until the centre drill "pilot" is well in and the 60 degree taper cutters have started to "bite" and than you can almost go back to just winding the quill in and out of the tail-stock. If you start off with a drill just a bit bigger than the "core" of your larger drill/s the larger drills will pretty well centre themselves and need no more support once the outer diameter of the drill has centred the job.

I do pretty much what you are doing - always have. I extended the centre drill right out of the chuck and have the quill a long way out as well and just let them "float". They will self-centre most times on their own - sometimes with a bit of help.

If that lathe of yours were mine I'd leave it until it really needs doing as if you are satisfied now - why bother?


Well, that's the thing. If the quill is held too rigidly, and it's too low--I'll be breaking drills. I'll be able to use the center without getting a cheater, but not be able to drill. Maybe I'll need those shims between the base and upper part of the tailstock like Fasttrack said, eh?

That video on peck drilling was a good one. This machine doesn't lend itself to working with the small diameter drills. I usually work with larger stuff, and haven't broken any drills, but I can see that good technique would let me drill smaller holes with good results. Taking a little weight off that oversize chuck would go a long way towards finding center and saving drills, too.

Well, plenty of ideas. i'll have to see what i can come up with.

Jim

Jim2
03-01-2010, 10:16 PM
Here's a follow-up to this thread.

I bought some shim stock from Enco on sale, and made a shim for under the quill. It is held in place by the key that prevents the quill from turning inside the tailstock. I'm using 0.003" thick piece, but I made up another one that is 0.002" if that one doesn't work out. Here's a pic

http://img.photobucket.com/albums/v280/jasch/Leblond/Tailstock/Quill-Shim.jpg

I wanted to add DRO capabilities from the start. Here's what I came up with:

http://img.photobucket.com/albums/v280/jasch/Leblond/Tailstock/Finished-01.jpg

More pictures at

http://smg.photobucket.com/albums/v280/jasch/Leblond/Tailstock/

Jim

oldtiffie
03-02-2010, 01:36 AM
Nice job Jim.

What ever works works.