Well... I've more or less got my CNC hotwire set up now - I think
It all runs nice and smooth during axis test runs, and I downloaded a neat set of 'Foam Cutter' screens for Mach3. Just have to make the mental adjustment of thinking/talking X/Y and A/B axes instead of X/Y Z/A, but that's ok. In fact, I can better visualize XY & AB anyways
When I do a test cut, the cutter makes a hell of a noise. There's an enormous amount of harmonics and resonance going on
I've set my Mach3 up to run "mm" as the native units instead of inches. The cutter runs 3/8-12 ACME threads, so my 'steps per unit' are 94.49 instead of 2400, with a velocity of 600 (i.e. 600mm/min = 10mm/sec). As I said above, that all runs really sweetly when I jog the motors around the axes at 600mm/min, but when the Feed Rate is set to 200 in the G-Code, the cutter makes horrible noises when moving the axes.
Is this normal?
Do I perhaps need to change the steps per unit, or the axis acceleration?
The NEMA24's on the cutter are rated at 200 steps/revolution - and I'm pretty sure that that's full steps (no half-step, micro-step etc. options).