Jim Reed wrote:

This is my first lathe and I am having trouble with using a cut-off tool. I
usually am cutting of mild steel, although I've tried stainless, brass, and
some junkyard shafts. The diameter ranges from 6" to 1". On almost every
cut I have the cut-off tool popping at times and chattering at other times.
All of my cuts look as though I used a machete and chopping motions while
the lathe rotated.
I have made sure the tool is 90 degrees to the work, that the tool meets the
work at or just below even with the center, and that everything is tight. I
have broken a few cutoff tools, and once hit the wall over 20 feet away with
the broken piece. (Yes, I wear safety glasses). I am using a tool by
Wholesale Tool (wttool.com), page 156 of their latest catalogue. It is a
"P-Shaped M-2 cut off blade". Specifically, the P4 - 5/32X11/16X5. I flood
the cutting area with oil. I have tried almost every speed on the lathe -
roughly 150 to 450 RPM. My lathe is a Reed-Prentice 16X54, and the
toolholder is an oriental Alorix knock-off. I've used a new 15" four jaw
and a 8" three jaw chuck.
What do I check/change?




Your best bet is a carbide insert. Costs a bit more but the results will
be sure to satisfy. The tool holder has a blade with a notch on the end
the insert presses into and can be replaced by popping out with a tool
included.
These inserts have a geometry with folds the chips, making them smaller
than the groove being cut. It makes for a free cutting action and
prevents chips from building up in the cut.

Fred