I purchased a Grizzley 13 x 40 lathe at auction for cheap. The tailstock is about 0.005" higher than the headstock. I have a surface grinder and could grind the tailstock baseplate down by 0.005", but I am wondering if it would be simpler to shim the headstock. Any suggestions?
That makes your tailstock cuts a smidge under .0025 taper. Maybe.
Have you actually measured the actual cut?
Gunner
Political Correctness is a doctrine fostered by a delusional, illogical liberal minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.
Me think you measured wrong. I would double check. However, it is Chinese and it is possible to have this error, as their QC is non-existent. Yes, you can shim, but you must have a test bar and a precision level. See the previous threads on this subject. Steve
Is it a problem for the work you do? The tailstock will wear with use so eventually will be the same height as the headstock. So if it is a problem then shimming the head stock now, will let you remove the shims when the tailstock wears.
If the headstock spindle is really parallel to the ways, then shims would probably be a good idea. You can always remove them if need be, a whole lot easier than putting back the metal you ground off the tailstock. But again, I'd be real careful about checking the parallelism of the whole thing - not just the bed leveling and HS-TS alignment,
BTW - this thread is totally off topic, Despite the name, this group is only for discussion of extreme political views. Now, if you referred to the headstock as the "left end" end the tailstock as the "right end", we might have something to discuss :-)
Even then it would be off topic. .005 is almost in agreement. Now if the left side and the right side were mismatched by an inch or so, it would be on topic.
It is traditional for the factory to make a new tailstock a few thousandths higher than the headstock. This is not enough difference to make a problem with the size of workpieces between centers on a 13" lathe, and it means that for many years as the tailstock wears it will be getting closer to perfect before it starts getting worse.
Dont do head , unless it needs it , work on tailstock .
I use an old Printer Platten Bar about 5/8 " diam . I do vert first , i clock vert with DTI and zero the DTI , then move away from head about 4 inches , repeat DTI . If DTI reads same plus ,, as minus , Vertical is spot on . do horizontal same ... When ya scrape the under side of head , theres too much area , too little PSI . i scrape with abandon , maybe .003" except at corners . Then carefully scrape "straight down" using Hi-Spot blue , Prussian blue .
Tailstock is not critical , so learn on it . You can allways shim up a mistake . I saw V-ways on a a lathe ,
How about a quill in tail stock . ballbearings ( 6007-2RS) sliding in a large cylinder , like a quill . Cyl is adjustable for wear , hard OD of ballbearing slides in the cyclinder . Now i can spin drill bit one way , while head spins work opposite .
BTW Id appreciate the tapered roller part numbers . Id like to DIY some machinery . Does anyone have the part numbers / sizes .
Harbor Fright tried , but it was too messy , they cud not figure the part #'s .
I need these or the #'s from a 10Ton truck differencial , Carrier is smaller than pinion , so i prefer carrier . Thanks for the effort ...
I shall quote literature here and not my negligible experience:
Tubal Cain in his book on workholding in the lathe states that the vertical displacement of the headstock is much less important than horizontal displacement. Cain quotes a taper of 0.0004" per foot for a vertical error of 1/64".
There is another source stating the same and giving a mathematical proof but I cannot find it right now.
All's I know that for a *horizontal* displacement a 1/64" error would give a taper of 1/32" over whatever length the workpiece was.
The biggest problem of a tailstock being higher than the spindle is when applying small cutting tools. For example, if you use a #1 center drill, it's likely to snap off the tip instead of cut. That's due to the tip trying to act like a fly cutter.
You can get around this issue by holding the tool by only a short amount, so it is free to wander slightly in the chuck. It will then seek center, assuming you address the work slowly. Once it picks up, it works fine.
In a few years, especially if one is not good about wiping and oiling, the base of the tailstock will have worn enough to approach dead center. After that, the problem reverses. Leave the damned thing alone and learn to work with it. You'll be happy if you do, and sorry if you don't.
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