Grooving and parting off require a rigid setup, which you may already know,
Tim.
Snug everything down except the cross feed, and even the cross feed if there
is much backlash in the feed threads.

Since you're grooving and not parting off, use the tailstock center to
support the workpiece unless it's impossible. Grooving and parting off test
the rigidity of the setup, so use of the tailstock center is an advantage.

A very sharp cutting tool with the proper relief angles and possibly a chip
breaker are mandatory. I find that a very slight front relief angle prevents
the tool from grabbing or self-feeding into the workpiece. When the front
relief is almost vertical, the tool tends to rub instead of self-feeding.

Make sure that the cutting tool is being fed as perfectly perpendicular to
the workpiece as you can get it.

A quality cutting lubricant applied right in the groove can make the
difference between success and, well, problems.

A slow spindle speed has worked best for me and depending upon the diameter,
it may need to be very slow.
Crawling slow is not fast enough for aluminum, but slow doesn't seem to be a
problem with mild steel.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Tim Wescott" wrote in message
...
RB wrote:
(a bunch of off-topic, probably skewed, political crap)

Thank you for your illuminating post.

Now, I'm trying to turn some fins into a replacement cylinder for a Cox
15. I basically made myself a narrow little cutoff tool, which started by
chattering a little bit, then rapidly evolved to chattering a lot, then
bound up, wrenching the cylinder blank out of the chuck and breaking the
tool.

Since this is a _metalworking_ group, do you have any suggestions about
how I may do thing _metalworking_ task?

Thanks.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html