Bruce:
>>The setup of acceleration in M3 is done starting at rest. The user tunes the acceleration based on how the machine performs in this test - with no control of jerk (pretty high at end points) as I understand the test. As it says in the docs - the limit is set mostly done by sound and pushing to failure and them backing off. I believe that if the setup were done with a jerk limit, the peak acceleration that the user would end up with would be higher than the acceleration you end up with in the standard test. This is because higher peak accelerations would be possible since they would occur (in the test) when the machine was already moving. This of course implies a different acceleration setup for Tempest M3 than stock M3. Is that clear?
If I understant you , thats only true in non-linear acceleration. In Mach3 ( linear accel), setting it to a jerk limit woudl reduce the end accel and speed as its that that causes the jerk in the first place, in Tempest ( sinusoidal accel), its very true that the accel shoudl be set with a jerk limit. It uses MAch3's simply because tempest is mach3 with sin accel, so I didnt rewrite the motor tuning. In fact in Tempest one shoudl set the accel normally, then increase it by about 30% as tempests use of sinusoidal accels will allow the motors typically to do about 30% better accel.
However, since sine based accel uses about 30% more time than linear ( on average ), the end speed is then simplyequalized, not increased ( on average) by havingthe accel set higher.
The problem in tempest is that while Gcode motions use sine accel, jog doesnt, so you have to be carefullnot to make jog too jerky when tuning. If Jog was sinusoidal as well, then simple
motor tuning by sound woudl be fine.
I advise simply tuningmotors in jog as high as you can without losing steps.. Tempest can usually handle that high an accel..
Art