I am working on a large piggy bank project 10” in diameter and 10” tall. My intention is to finish the O.D. using the rounding toolpath, which I’ve completed successfully. I’ve also included a cove top and bottom, as well as a pair of ½” spirals around the O.D. using the fluting toolpath. All of this seems to function as expected, however, there is such a disparity between the Y axis speed and the B axis speed, that I am ending up with a severe burn on the coves.
I am running the router as slow as I can (10,000 rpm). The rotary axis chuck is manufactured by Sherline ( and limited to something less than 3000rpm), with no visible means of adjusting its speed. I’ve no idea how fast it runs, but I’m guessing 3 rpm. (fast mode using the keyboard – machine control is much less ) My CNC is driven by Mach 3, and is a 3’ X 3’ machine manufactured by Velox CNC. I suspect that I’m well within the capability of the hardware, but cannot seem to overcome the slow speed difference between Y axis and rotary axis.
Can anyone suggest a fix for the speed difference???