Thought I’d share my progress with cutting steel bar. I’ll update this thread with progress as I keep tweaking things.
I got so far as to cut 3/16" steel bar in a single pass using trochoidal milling. I’m also blasting the part with quite a bit of air though the nozzle that’s built into my lower mount ~50psi for both chip removal and cooling. All of the cuts here are made with a single flute 1/8" cutter. It’s slow going so I wouldn’t expect to cut anything large and I don’t think I’ll get much more aggressive than the settings below without cooking cutters.
5mm DOC (material is 4.8mm, however)
1.25% trochoidal step
50% trochoidal width
I haven’t played around with plunge speeds yet. That’s next.