"Jim Wilkins" wrote in message
...
On Jan 15, 12:57 pm, "Bob La Londe" wrote:
"Jim Wilkins" wrote in message

...

On Jan 15, 1:24 am, Bob La Londe wrote:
...Then I
went to actually use it to setup a work piece and whizzzz.... the
neat little makes a dandy top on the mill table until it drops in a t-
slot. ...

How fast did you spin it?

Too fast I guess.

Mine works well at 600 RPM, just went down and checked it. I think I
had one spinning a little over 1000 on a Bridgeport once.

Sorry I can't help you on CNC feeds. I learned the limits on a manual
mill first, by burning and breaking tools, then by the audible
complaints an overloaded machine hopefully makes just before that. I
feed a CNC machine gently to avoid breaking a valuable prototype.

The very few times I've done a small production run I worked up slowly
to an efficient rate. When I damaged a part I kept it in the batch to
try out the next cut on.

Yeah, that's basically how I am learning. Gouging work pieces and breaking
tools. The thing is I am about ready to step up to some bigger (more
involved) projects, and I would sure like to push the envelope for speed.
At feed rates I have found to be safe my first one is about 35 hours run
time estimated. That's with coolant and I can't use a water based coolant.
I am concerned about flash, and I do not want to sit there for 35 hours
while the part runs. If I slowed down enough to cut it dry and not worry
about heat I would work harden the material. Even if I didn't it would
probably take several tool changes and re-zeroes to finish the job, and take
about 5 days. (That's for one half of the project. LOL. Its two pieces
equally complex.)