I am doing some raster 3D carving, and noting that the speed seems limited in ways that can't be explained by the actual machine.
I have a 6"x6" relief with a 1/16" ballnose doing 20% stepover. So 2880 linear inches. Feedrate 400ipm. By itself, 2880/400= 7.2 min. Which, I understand, decelerating to a stop to lift up over a feature with an abrupt change in Z-height takes extra time. And I watched it, on flat areas it rips right across but really slows to a crawl across detail with Z-movement.
The machine's XY axes were set at 600 ipm 40 in/sec/sec accel, z set at 200/50. This got 37:30 runtime. So I play with possible more aggressive numbers for acceleration and get only modest gains.
For information purposes I went in and entered the max acceleration Mach3 allowed, which was 187. Well it lowered the runtime some, to 22:44. Tried kicking Z up to 400 ipm and still no improvement. Kicked XY down to 400 ipm max, which opened up acceleration to be set to 281 in/sec/sec. Still no significant change in runtime.
Well if acceleration was the limiting factor, those crazy high acceleration numbers should have brought it close to 7.2 min. But no dice.
Had a theory "maybe the Ethernet Smoothstepper has a processing limit" so I changed to a profile with Parallel Port. No difference.
Loaded Mach3 on a different PC just in case somehow it was looking at processor speed and slowing down the run if the PC couldn't calculate that fast. No difference.
Changed Kernel Speed and restarted. No difference.
Doubled the ipm in the file, no effect.
So it seems like motor performance is not the reason time cannot be brought below 22:44. Mach3 is introducing some sort of speed limit across detail that has nothing to do with acceleration- what is it??