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Harold and Susan Vordos
 
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"Greg Postma" wrote in message
...
A couple of weeks ago, I asked if any of you could reccommend a tube
bender for a project I have been working on. I think it was Paul that
suggested Wagner in Milwaukee. Well, I picked up the bent tube yesterday
and they did a nice job. My cost was about $400USD for 15 pcs (2 bends
each). Not to bad, and I will be able to polish,do my magic and ship on
Friday. Right on time!!!

Thanks to all who made suggestions

Next.

I posted a couple of months ago about my little Atlas/Craftsman lathe
that my FIL gave me. I've been playing with it and I discovered that I
have a runout of about .008-.009" with the chuck on. At the spindle I
have about .0005" (1/2 a thoushandth) at the spindle. It first, I
thought that I might have bad bearings on the spindle, but .0005" seems
pretty good, so most of the runout must be in the 3 jaw. Any suggestions
to get rid of the runout?

Greg


Grant's information is good, but before you jump through several hoops, you
might want to clarify what you said. I gather that you have only .0005"
near the spindle, but a distance from the chuck it's more----the .008"/.009"
you mentioned. If that be the case, you could have a sprung chuck, which
is very likely on such a small one. Often times a short piece is chucked
at the very ends of the jaws, then over tightened. The stress permanently
deforms the chuck slides, causing the jaws to grip only at the rear. It's a
major source of chatter and runout on long objects.

Check the jaws by inserting something hard and ground----an end mill shank,
for example, or a drill blanks if you have them. You want this item deep
in the chuck, so the jaws grip at the very back, or inside the chuck body.
Snug up the jaws (lightly, don't get down on the wrench), then see if you
can insert a feeler gauge between the jaws and the chucked item at the
outside end. If you can, the chuck is sprung. It can be salvaged by
grinding the jaws, which we can talk about if you find that's the problem.

Harold