How to align head stock to ways on 10F?

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sandmanred

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Is there a method to align the head stock to the ways on a 10F? I don't see any obvious adjustment for it. I've check my way for straightness and wear and they look pretty good. The outside measure 5.748 from the head stock out most of the as close as I can measure with a caliper. I also ran the procedure where you trace a round bar mounted on centers twice, once at a 9 o'clock and a second time at 3 o'clock and run the math to sort out bar shape from tail stock off-set from way straightness. I'd estimate way straightness with 0.5 thou over the entire working length. However I get a taper of about 1 thou on the radius per inch of length when I turn a cylinder grabbed only by the chuck. A check with an indicator over a 10 inch long test bar shows about the same mis-alignment between the head stock and ways. Thoughts?
 
I don't know of any adjustments for that, it was set by the factory and can vary a bit. You could take off tiny amounts of metal on either the headstock or the bed and then fill the opposing corners with epoxy. Big job though, I would set aside a couple weekends at least, with cold beverages and snacks aplenty
-Mark
 
You have not yet confirmed that the problem is headstock alignment and not due to the chuck. Assuming that the 3MT female taper in the spindle is still OK, I would suggest finding a 3/4" or 5/8" dia. test bar and 3/4" or 5/8" 3MT collet and repeating the test with those before I even thought of loosening the clamp and locator bolts and twisting the head stock. Mount the collet and test bar and tighten the draw bar. Then indicate the runnout (TIR) right at the collet and at the tailstock end of the test bar. marking the high spot at each end. If the runout is greater at the tailstock end than at the spindle nose, rotate the spindle to put the high spot at the tailstock end of the bar pointed at 6:00 O'clock. Then re-mount the indicator to the tool post or however you do it and repeat your measurement run of the carriage over the length of the bar.

A 1" diameter test bar would be better but unfortunately 3MT collets only go up to 3/4".
 
pontiac428 said:
Sounds like you need Rollie's Dad's Method!

The procedure is here: http://manuals.chudov.com/Rollies-Dads-Method-of-Lathe-Alignment.pdf
Click to expand...

Rollie's Dad's Method is as basic as one can get, and probably the most accurate. That and a piece (roll) of aluminium foil and the rest of the day is all that is required for any sized machine. A straight bar is nice to have as a reference, but any old axle is straight enough. Paper shims will work, foil shims are better. The rest is time. . .

.
 
It seems to me that if he has leveled the bed ways to .0005" the problem is likely not a twisted bed, but an actual problem with headstock alignment; on a lathe with vee ways, it is an easy fix by shimming the vee under the headstock of equal size one at each end of the headstock on opposite sides of the vee way. I have done this on several lathes that I have owned to get them to cut straight, given the ways are level; with a flat way lathe this is more problematic, if the headstock fits tightly between the ways, some metal would need to be removed from the tongue under the headstock ans shims fitted tightly until correct alignment is achieved.
 
I loosened and re-tightened the head stock and with a little push as I tightened got 2/3 of the mis-alignment out. Then removed the head stock and filed a bit on the inside of the way on the very end re-installed got parallel between the head stock and ways within 0.001 over a 10 inch test bar. Thanks for your help!
 
Is there a good video of Rollies Dads Method out there?
I got to the point where the more I read it the worse my out come!
From my “test” I have a .012” taper over 8” ? Smaller Dia at the
I have a Smithy 1220
 
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