Hey all,
Thanks to your help, I was able to successfully cut my parts... but I have questions.
The G61 (exact-stop mode) command did solve the problem, but at excessive cost in my opinion.
I could see the excessive accel/decel motion at every segment (just as cautioned in the G-code reference manual).
I could also solve it by slowing the motion down, but I had to slow down much more than I wanted to. 50 IPM got it close enough (though there was still _some_ corner cutting evident).
The job was initially set at 297 IPM, which, it turns out, is faster than our machine can go. We have max speed at 190 IPM, max acceleration at 6 IPS^2. This, because have a rather heavy X-carriage with two spindles. We're going to be reconfiguring soon to single spindle & will probably change acceleration at that time.
Still, this behavior seems strange to me given the use case. Note that my tool path has a 'cusp' at the corners of interest. It's supposed to be a dog-bone, which is a fairly common technique.
I would think this angle too sharp for the constant-velocity logic to kick in. I expect this kind of cornering logic to take effect only at corners with shallow angles, ...as produced by simple CAM packages that render short line segments to simulate an arc instead of rendering a G2 or G3 command, for instance.
Is there a way to program the 'turn-angle' at which the constant-velocity logic takes effect?