Running a CNC Router with a rotary axis.
Running a vcarve toolpath (lots of short movements and moves up to safe z for rapids) that carves on a cylinder.
Using CV I get a clunk from the motor on the z-axis (probably losing steps) on a lot of the G00 moves to up safe z which preceedes a G00 move to a new A. Sample code that clunks:
N680 G1 X0.0965 A-19.6482 Z0.1927
N690 G00 X0.0965 A-19.6482 Z0.4050
N700 G00 X0.0965 A-30.9263 Z0.4050
I get the clunk from the z motor on line 690.
If I switch from CV to Exact Stop, I don't get any clunking. This toolpath runs very smooth with exact stop set. Changing motor tuning (velocity / acceleration) makes no difference with CV, unless I drop to super low levels that would be crazy to use. Tried different values for CV distance tolerance and angle, but it didn't help CV run this toolpath smoothly.
If I take the exact same toolpath and run it on a flat surface (using y instead of the rotary A), I can run with CV and it is completely smooth. No clunking on the G00s.
I don't have any long arcs (with multiple segments) in this particular toolpath so I can run it with exact stop. But that may not always be the case.
Is there some setting somewhere when using A as a rotary axis that will allow CV to work like it does in the flat world?
It's almost like Mach3 is picking up the acceleration from the A axis (which is really high) and using it for the z axis when it is doing the G00 move to safe z with CV on.
My A Axis (rotary) is velocity 18810 and acceleration 3151.
My Z Axis is velocity 200 (inch per min) and 50 acceleration.
I could see where slamming the z motor with an acceleration of 3151 might result in a clunk or two.
I'm new to Mach and still learning the ropes, so I apologize if I didn't explain things clearly. I tried searching the forums but didn't find anything that helped me.
Any and all help welcome.
Thanks,
Ed