Wes wrote:

Jim Chandler wrote:


I have a Smithy 1220 lathe/mill and was turning a 3/16" threaded coupler
down yesterday and I noticed that there is apparently a taper in it.
The end away from the chuck is about .006 wider than the end near the
chuck.


What was the l/d (length to diameter) ratio of the part your were machining?
Can you rig a test indicator to your carrage and indicate the side of chuck?
Might give you an idea if your headstock is mis aligned with ways.

Worn jaws can do it also. Wooped ways also.



Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

The diameter of the part started at about 1/2" and the length is about
2". I an turning it with a 3/16 grade 5 bolt run all the way through it
and am chucked (three jaw) on the bolt. I suspect Karl was correct and
I'm getting deflection that I hadn't considered. The machine is just
over a year old so I don't think that there is excessive wear in any of
the parts, especially since I've only used it a few times (not as many
as I'd like). Thanks for the reply. Every bit of information helps.

Jim