"Karl Townsend" wrote in message
...
On Tue, 21 Jun 2011 06:38:52 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Karl Townsend fired this volley in
m:

Based on my experience with one lathe, I'm no longer a great fan of
leveling. I bought a very expensive level for our Mazak M4 lathe,
16,000 lb. 22" X 72", and leveled it perfectly.

Then chucked a 30" long 6" diameter rod. The idea here was the biggest
thing that could be run without a tailstock. A light cut showed a
taper. Started raising one of the legs on the tailstock end and got it
to cut true. Anyway, level shows twist, machine runs right.


I'll bet dollars to dougnuts that your headstock was/is out of alignment
with the bed. Unless there's a serious belly in the ways, and you're
cutting _exactly_ on the center of the work, a leveled and trued bed
cannot turn taper from the chuck unless the headstock is mis-aligned.

Rather than "not being a fan of leveling", I'd take it that your leveling
exercise disclosed a previously unknown problem. In fact, it did its job
perfectly, and I'm afraid you've perverted your setup to accommodate the
problem, rather than fixing it.

Headstocks _do_ get mis-aligned.


I'm sure you're technically correct. No doubt this lathe had a schmuck
in its past. But raising one leg and test cutting took maybe an hour
tops. Tearing the headstock off and re pinning or grinding etc.
*should* fix it at a cost of many hours. For most, my suggestion is
just make it cut the best you can without a rebuild.

Now if you're making parts for NASA or Medtronic, this advice would
not apply.


Leveling is especially important for shipboard use.

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