In article om,
says...

I cut off a 10" piece and trued it up and the hogged out the middle to
form the collars. I had about 8" hanging out of the collet. I sharpened
the cutter again and honed it with a small radius and took a cut across
the collars at 1000rpm and .00085 feed. The bar chattered terribly on
the end but cleaned up beautifully at the headstock end.

You could go up to a larger diameter piece of steel stock,
do NOT use a radius on the end of the tool. Keep the feed rate
and spindle speed down and you will probably get out of the
chatter zone. 1K rpm is probably too high.

The radius on the tool is probably the issue, how are the
spindle bearings on this machine?

You can also reduce the overhang to six inches and try again.


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