# Completely dickered 12X36 spindle, options?



## Mwmx54 (Jul 30, 2017)

Hey guys!
I picked myself up a an old craftsman badged 12x36 (with the timken bearings) a few months back and have been having a great time learning to use it. I have so far made a little gear indexer and cut my own gears, with the milling attatchment that came with an old 9" atlas (metal craft badge I think) it was trashed but came with lots of tooling and other neat stuff, I like having parts machines for my parts machines so my latest project has been getting my lathe level and aligned and I have come across a problem, I noticed no matter what I did I couldn't get the spindle to run true, so I decided to try bluing my collet chuck and noticed hey, only about 1/2-3/4 of an inch is in contact, so I measured the through hole of the spindle, and guess what? Someone bored it out! So I decide I have a little room to try to enlarge the taper and still have a usable but slightly larger mt3, so I spent way too long setting up my compound to cut the taper, I took a few thou out of the taper and now get about 1-1/4"-1-1/2" of contact on my dead center, but my collet chuck is now too small to fit. So I looked through epay and there are quite a few used spindles, for 70$ plus! Or I can get a whole headstock for about double, and have some more spare parts. My other option is to make a new spindle, so I checked the online metal suppliers and I can get a 12" bar of DOM that is 2"OD and .75"ID is this a suitable material, I also have a few feet of 3" C.R. Bar, but that would take a lot of machining... but maybe it's a better material? Not sure what used originally? Plus I have it on hand. Sorry for all the words, think of this as my introduction and a question. Also, if anyone has a spindle laying around let me know. We could work a trade, I have all sorts of stuff for these lathes including a complete 9" with a few good parts still. Not the spindle though, it was trashed when the Babbitts that it ran on failed.
Thanks!
Here's some pics don't mind the messy garage
I added the 3/4" leadscrew and put a newer carriage with auto cross feed, as well as an AXA qctp


And here is a couple of my gears I made.


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## Groundhog (Jul 30, 2017)

Nice looking gears!


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## extropic (Jul 30, 2017)

Morse taper 3, taper is .050195" per inch (on the diameter). Therefore, if you increased the MT3 by .005" diameter, you sank the gage line (.93800" diameter) by .10".
Can you cut/grind a little off the back of the Collet Chuck head to let it seat in the taper you have?
Buy a 15/16 (.9375") bearing ball and measure how deep your gage line is from the front of the spindle.
That will tell you how far you'd have to "relieve" the collet chuck head.

If the MT runs true now and has an acceptable form, I'd avoid making a new SOFT spindle. YMMV but I would consider that a waste of time.
If you can't help yourself (have to make a new one) I suggest that it's not as simple as it may seem to make a quality spindle.
Don't forget that CRS is loaded with stresses that will want to relieve as you cut it and may distort over time. I don't have any experience with DOM tube in those dimensions. 
If you used a material that could be hardened, heat treated and finish ground, you certainly would have improved the lathe and exercised your skills and wallet.

If you must replace the spindle, IMO, buy a replacement part.

I don't know exactly how easy it is to bend a spindle in your lathe, but IME, lathe spindles are not easily bent.
Runout problems (not bearing related) are usually the result of dings and damage caused by mating dirty parts.
If the MT3 is a problem, I'd try a light "cleaning" by hand with an MT3 finish reamer long before deciding to recut it.


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## whitmore (Jul 30, 2017)

I've heard (but never seen it done) that if there's a few thousandths missing, you can get a  hard
chrome plate, and build it back up... but only a few thousandths.   Then, you'd need to get it
ground to accurate MT3.    Not sure, though, that the surface would engage like a good taper
should, 'cuz now it's the wrong material.    It might be worth asking about.
For a quick fix, a shimstock  MT3.03/MT3 adapter would be as easy as making
a funnel from sheetmetal.


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## Mwmx54 (Jul 30, 2017)

The main concern is that whenever they bored the ID of the spindle, that it warped, I considered removing some material off the back face of the collet chuck, but it seemed like it would need to be a lot. It's a pretty loose fit now, it feels like atleast 1/16-1/8" of an inch of wobble but the chuck always fit almost the way in. Ive taken the spindle out of this machine before when I first got it to clean everything, it was pretty bad, bearings were all good though. I'll keep looking for a replacement spindle, I imagine it would be one of the expensive parts to get straight from clausing right? They wanted over $700 for a leadscrew. But half nuts are pretty cheap.


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## Mwmx54 (Jul 30, 2017)

As far as reaming goes, that would have been ideal, I had no mt3 reamer though, and it was already screwed up, couldn't make it worse, my cut mt3 blues very nicely though. And my dead centers still stick out atleast 1.5" to the tip. Still pretty worthless not being able to use a collet chuck though. I should have known that such a light taper wouldn't take very much to move the whole thing as far as it did.


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## Mwmx54 (Jul 30, 2017)

What do you guys think about boring my spindle taper more, and taking an mt3-mt2 sleeve to where it fits all the way in touch wif th the tip of the spindle, then gluing and pounding it in permanently? And boring it back out to mt3. Or even taking an mt3-mt4 and turning it down a little, just so I can get full or atleast more than 1.5" contact along the taper.. and does anyone know exactly what material the spindles are made from?


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## extropic (Jul 30, 2017)

Mwmx54 said:


> What do you guys think about boring my spindle taper more, and taking an mt3-mt2 sleeve to where it fits all the way in touch wif th the tip of the spindle, then gluing and pounding it in permanently? And boring it back out to mt3. Or even taking an mt3-mt4 and turning it down a little, just so I can get full or atleast more than 1.5" contact along the taper.. and does anyone know exactly what material the spindles are made from?



Won't a MT2 sleeve reduce your "through the spindle" size substantially? And, wouldn't you have to buy an MT2 collet chuck (to achieve what you said you wanted)?
If your collet chuck's shank is replaceable, just make a longer MT3 to fit your spindle, as is.
I think it would be a bad idea to remove more metal from the ID of the spindle. I wrote earlier "lathe spindles are not easily bent". If you keep cutting, you may prove me wrong.

I have no idea of your financial circumstances, but a replacement spindle from eBay is looking more attractive all the time. Invest in a finish reamer for your taper(s) also.
In the future, take extreme care to verify that your tapers are clean and free of burrs before mating.


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## Mwmx54 (Jul 30, 2017)

You're right, but what I meant though was just removing a little more from the spindle taper, so that an mt3 to mt2 adapter fit all the way in flush with the tip of the spindle. Then boring the sleeve adapter back out to an mt3. Leaving probably too thin of a sleeve left though, I could also make a long mt3 taper as thick as I want, then boring as much as I felt necessary from the spindle to get the right thickness of what would be a sleeve(bushing) semi permanently glued or even tig welded in place, I would be no worse off than I am now, as I'm fairly certain my spindle has a bend from being bored out to about .880" if I recall correctly. I have a sleeve that when put into the taper, still extends past the the nose about .75". So couple more thou out of my spindle and it should fit all the way in. But you are right. $70 on a used hopefully true and not dickered spindle off eBay is the ideal route. Just can't ever be sure of what your getting from the bay.


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## extropic (Jul 30, 2017)

Mwmx54 said:


> You're right, but what I meant though was just removing a little more from the spindle taper, so that an mt3 to mt2 adapter fit all the way in flush with the tip of the spindle. Then boring the sleeve adapter back out to an mt3. Leaving probably too thin of a sleeve left though, I could also make a long mt3 taper as thick as I want, then boring as much as I felt necessary from the spindle to get the right thickness of what would be a sleeve(bushing) semi permanently glued or even tig welded in place, I would be no worse off than I am now, as I'm fairly certain my spindle has a bend from being bored out to about .880" if I recall correctly. I have a sleeve that when put into the taper, still extends past the the nose about .75". So couple more thou out of my spindle and it should fit all the way in. But you are right. $70 on a used hopefully true and not dickered spindle off eBay is the ideal route. Just can't ever be sure of what your getting from the bay.



The eBay definition of "USED" includes the requirement that the item be fully functional.
Read the sellers description, If description is lacking, communicate with the seller to ask questions and tell them what you want (A fully functional spindle w/ good bearing journals and MT3 taper?).
If item arrives "not as described" you get all your money back including return shipping.

Good luck. My work is done here.


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## brino (Jul 30, 2017)

Mwmx54 said:


> don't mind the messy garage



You'll fit right in!
Welcome to the group.
-brino


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## wa5cab (Jul 31, 2017)

MW,

I think that you have probably already spent more time fiddling with what was a ruined spindle when you started than was prudent.  I wouldn't waste any more time on it.  It shouldn't be hard to find a replacement.  Atlas made the same 10-31T 1-1/2"-8 thread spindle for Timken tapered roller bearings from about 1935 through March, 1981.  

As far as bending a spindle goes, the only valid bent-spindle reports that I have ever seen on any of these lists have been the little 0.550" diameter  with a 1/4" diameter through hole spindles used in the AA 6" lathes sold by Sears in the 1940's and 1950's.

We do not know what material Atlas used in the 10-31T.  As it is still available from Clausing, they won't give out the drawing.


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## Mwmx54 (Jul 31, 2017)

Okay, thanks for the help, you all have very valid points. I often trip over a dollar to pick up a penny, but this is my hobby, and I enjoy this kind of thing, as I'm sure, some here know what i mean, I could absolutely go out and buy a new spindle or even a perfectly functioning machine, but my mind just refuses to let me do those things, I get a sense of accomplishment when my cobbled together project or idea turns out well. Also, restoring something that you are using to learn is a great way to learn something. In my mind. Except when something like a tweaked spindle makes you chase your tail for days.
However I don't believe my spindle is "bent" in the general sense, but must be warped from boring due to possible internal stresses? all I know is that it was not right. Nothing added up correctly and learning that it had been bored made me think this. I'll grab one off eBay and see how it goes, maybe play around with the current spindle while it's on its way.
One more thing, are the 10 and 12" spindles the same part? And are they same for Babbitt and timken models? I'd assume this would not be ideal due to possible wear on the bearing journals


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## Tozguy (Jul 31, 2017)

If the spindle has enough meat to it, the MT4 to MT3 insert idea sounds like a fun fix to me. I would attempt it if only out of curiosity. 
Or would an MT3 to MT2 sleeve be thick enough once bored out?


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## Mwmx54 (Jul 31, 2017)

I may still try, just to see if I can! I also have a mt3 finish reamer on the way, we'll see how good the ol' ussr made them..


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## Mwmx54 (Aug 3, 2017)

One more question, I recall when I had the machine apart to clean, that the bearing nearest the chuck did not want to come off the spindle, I may need to get it off to reuse when my new spindle shows up, probably since the new spindle comes with just the bearing but not the outer race, not sure if I can swap one but not the other or if the bearing and races should be kept together.. or even if the bearing that comes on the new(used) spindle is any good.


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## wa5cab (Aug 3, 2017)

The large cone is a light press fit on the spindle.  Theoretically, cups and cones are interchangable.  But as you have no way of knowing what the cone on the replacement spindle has been subjected to, I would replace both.  

Remove the spindle with a piece of pipe or tubing bored to be a slip fit over the flange near the threads.  Length should be sufficient to press the old cone past the first diameter change in the spindle  You will need a smaller bore tube to install the new cone.  In both cases, use a press, not a hammer.


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## Mwmx54 (Aug 3, 2017)

Thanks wa5cab, and thanks for all you do on this forum, I have spent many hours over many days learning about these machines by reading the posts that you have written, as well as others, but when it comes to a specific question about these machines it would seem you really know your way around them.


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