Rereaming tailstock quill

F

f21sh

Guest
Hello All
I am a newbie home shop guy. My tail stock quill needed to be replaced the guy who owned the lathe before me spun something in it. The replacement quill is not the best either. When I tried aligning the tail stock it is .015" high. No torquing that amount out.Therefore I was hoping I could purchase a MT#3 reamer place it in the headstock spindle and re-ream the quill aligning the tail stock (quill bore) with the spindle bore?
I have leveled the lathe and checked the headstock alignment with the ways everything is good to go. When I using the old quill I was able to align the tail stock .0015" high, fore and aft dead on. The newer MT#3 quill bore is what is off. Any input appreciated.:D
 
I would double check everything on the new quill before doing anything else. You may have done this, but .015 is a bunch to be out if the quill is a good fit in the tailstock bore, and I find it hard to think that whoever made the quill is that far off aligning the internal taper to the outside diameter. If the quill is a good fit in the tailstock bore/body, and you have confirmed the runout, then the fix is to mount the quill in a 4 jaw, indicate it in, and properly bore/grind the necessary taper (or send it back to the manufacturer for a new one). I don't know how you would put a reamer in the headstock and cut properly into the tailstock (can't clamp the tailstock down properly, and the reamer will follow the original bore, as Butch says). Something is wrong here that you are not catching, but don't know what it is without looking...

Scott
 
Reaming not required.

Take a good hard look at that tailstock. Generally the tailstock body is two parts. The bottom part rides on the ways and is machined to accept the top part. The top part is machined to accept the bottom part. There are screws for adjusting the off-set of the tail stock. Between the top and bottom parts there is often a shim or shims. Tailstock height is adjusted by these shims. In the absence of shims then you must machine off the appropriate amount from the easier part to machine. This re-machining of the tail stock must be done correctly other wise as you advance the tail stock quill you will change the height of the tip or the amount of off-set or both depending which way or ways you botched the job. With this in mind it might be wise to machine the tail stock to receive shims if it does not use shims now.

Good luck,
Nic.
 
First thing recheck your machine level and twist. If the lathe has 6 or more jackpoints, releveling may fix the tailstock problem. If the lathe was disassembled for moving, recheck reassembly. Like the guys said above, 0.015" is a bunch.
 
He said 0.0015" not 0.015". 0.0015" is excellent. Tailstocks are manufactured a little high. Like the lock on a good double rifle. This makes it possible for it to wear toward, then past, "perfect" and maintain "good enough" longer. You want perfect all the time you have to tune it.
 
papapaul said:
He said 0.0015" not 0.015". 0.0015" is excellent. Tailstocks are manufactured a little high. Like the lock on a good double rifle. This makes it possible for it to wear toward, then past, "perfect" and maintain "good enough" longer. You want perfect all the time you have to tune it.
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Go back and reread it, he said 0.015" on the good tailstock. The old one which he said was out 0.0015" is supposedly wrecked??
 
P.S. Jerry, I had to look three times to make sure it was 0.0015, even after I posted that response. Lots of zeros and little dots for my old eyes. If I had a lathe that had a tailstock within 0.0015, if I mentioned it to anybody, it would be to brag about it. The old axiom:"Are you bragging or complaining?". comes to mind.
 
You are correct, I missed that first one. I often overcome the urge to comment, but not often enough. Thanks, Paul
 
papapaul said:
P.S. Jerry, I had to look three times to make sure it was 0.0015, even after I posted that response. Lots of zeros and little dots for my old eyes. If I had a lathe that had a tailstock within 0.0015, if I mentioned it to anybody, it would be to brag about it. The old axiom:"Are you bragging or complaining?". comes to mind.
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Paul, in any case in this country we all have more to brag about than complain about.

Happy New Year
 
tail stock

Restating
the new tail stock is only high by .007"-.008" ( half the swing of the needle from bottom of the dead center to the top, right). I'm using the method that Greg Tannel performs to align the tail stock. I'm trying to get it very close to dead nuts. I am in the process of getting a reamer to try and clean up the older quill. I have checked level and twist and alignment of ways and spindle everything great. Checking alignment using a 1.25" drill rod out to 14".
Thanks for the comments.:D
 
Toss the drill rod

and get Dave Kiff to grind you an alignment gauge bar, tell him that you want one like Speedy used, he'll know what you are talking about. What you will get is an alignment bar that is 1 1/2 “diameter and 16” long with centers in each end, that is ground from a heat treated and aged tool steel blank. Make a nice box to store it in, keep it oiled and take care of it. If taken care of, you will have an extremely accurate gauging tool that will remain consistent until your children’s children get tired of using it. Drill rod is close, but not close enough to being accurate for use when gauging lathe set up.

Nic.
 
f21sh said:
Restating
the new tail stock is only high by .007"-.008" ( half the swing of the needle from bottom of the dead center to the top, right). I'm using the method that Greg Tannel performs to align the tail stock. I'm trying to get it very close to dead nuts. I am in the process of getting a reamer to try and clean up the older quill. I have checked level and twist and alignment of ways and spindle everything great. Checking alignment using a 1.25" drill rod out to 14".
Thanks for the comments.:D
Click to expand...
If you want a small lathe to have perfect headstock to tailstock alignment, have at it. If you plan on keeping it that way, good luck.

The reality of machining as to barrel fitting, the 0.008" will not hurt the predrilling operation for the chamber. Using a floating pusher for the chamber reamer, that amount of misalignment will not cause problems either.

It's all according to whether you want to be a precision millwright or a precision gunsmith.
 
It's all according to whether you want to be a precision millwright or a precision gunsmith.[/QUOTE]

Jerry

Well said.

Dave
 
Wouldn't it be tough

JerrySharrett said:
If you want a small lathe to have perfect headstock to tailstock alignment, have at it. If you plan on keeping it that way, good luck.

The reality of machining as to barrel fitting, the 0.008" will not hurt the predrilling operation for the chamber. Using a floating pusher for the chamber reamer, that amount of misalignment will not cause problems either.

It's all according to whether you want to be a precision millwright or a precision gunsmith.
Click to expand...

to drill straight holes, say in things one wanted to thread or for some other purpose?
 
I don't think so Pete. The quill being off center by .008 will probably make the hole oversize by a might, but not .008 off center.
Butch
 
As I recall,

Butch Lambert said:
I don't think so Pete. The quill being off center by .008 will probably make the hole oversize by a might, but not .008 off center.
Butch
Click to expand...

My South Bend's tail stock quill is .0015 or so low, I was concerned about it. I think the front of the ways? on the bottom of the tail stock casting have worn in the front as it has been used. How can one measure to find it the tail stock quill is extending horizontally correctly as it is extended?
 
Some set up is required but...

Pete Wass said:
My South Bend's tail stock quill is .0015 or so low, I was concerned about it. I think the front of the ways? on the bottom of the tail stock casting have worn in the front as it has been used. How can one measure to find it the tail stock quill is extending horizontally correctly as it is extended?
Click to expand...

...It’s a fairly easy task to accomplish if you already KNOW that your headstock spindle is square and perpendicular to the bed and the bed is not twisted and that your chuck grips true to the headstock spindle. Take your gauge bar that you used to adjust your lathe and grip it in the chuck with slightly more sticking out than the travel of your tailstock quill. With the quill retracted into the tailstock mount a .0001 dial indicator on the tip of the tailstock quill so that the tip of the indicator will ride on your gauge bar as you advance the quill with the tailstock locked down. First check it with the dial indicator at 12 o’clock; this is the test for droop. Second check it with the dial indicator mounted at 9 o’clock this is the test for angularity.

Good Luck,
Nic.
 
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