Sterling Dump

[Heavy Metal]

Originally Posted by tc1cat

10,500 rpm should be fine if your feed rate is OK for the .015" end mill. 6500 rpm for the .250" is a little high but again OK if you are using any type of cooling. I noticed that you either have air or coolant lines for the tooling. If you use either, you should be fine.
That is one of my problems. No cooling of any type for my mills. Need to get an air compressor and start running air lines!!

Thanks Lynn. VERY helpfull. I do need to figure out what feed rate an .015" and .025" end mill can handle as well as safe max depth. Any experience there? Can I do .02 in one pass?? These are stub end so mill ends only .063" long w/ .125" shafts. I'll be doing some reading but always nice to find someone that already knows the answer!

Yes, I run an air coolant setup. Actually came with the mill - I bought it second hand from a custom cycle shop that had upgraded to a Tormach (drool). Little gizmo makes some pretty cold air! Coolant mist systems look pretty nice and seem affordable. Messy I suppose and would require air compressor anyway.

I know you are right about 6500 RPM being too fast (at least for the .25"). Maybe I left it there because I'm was always working in the 0.125" range. I better do a little homework so I don't dull my end mills running 'em too fast!

Originally Posted by Espeefan

Joe, I'm not a pro either, but what you do sounds about what I do. I usually just go by feel (manual milling, no CNC for me) and how the cutter sounds...

...I almost always spray some light oil onto the material I am working with, by hand using a spray bottle, and the end mill.

Nate - Glad I'm not the only one! It's amazing how much manual milling helped me understand what works and not. Can't "feel" anything w/ CNC and the math is only good so far anyway. I jumped straight in to CNC having never milled anything manually or otherwise. After a week or two messing around I sat in the garage one night running the Taig by hand (no graduated hand crank but does have big beefy knobs on it) and that did me more good than a weeks worth of reading books and web sites. Any specifics on the oil you are using in the spray bottle? Sounds like a good idea.

Joe