Microstepping increases resolution but not accuracy, you can easily lose torque in intermediate positions, any stiffness in the rotary will just add error. Perhaps the worst thing I have seen though is rotary error itself, the lower the reduction ratio usually means a greater error from the worm/wheel in the rotary. Here you see tooth width error at worm wheel tooth rate.
I was working at a clockmakers and I had some high count wheels rejected. This made me measure all the rotaries we had plus a gear set I had ready for the George Thomas design and a rotary we borrowed, only one a 1940's Boley was within any kind of spec. On this we made new dividing disks and cured our quality problem. As it happens my xmas project is to start to document the errors in this typical setup as used by many. http://www.archivist.info/cnc/wormtest/ The page is not yet finished I need to finish the tooth error average for the 48 tooth gear and the high resolution microstepping error, which currently shows as regular noise on the upper graphs. Dave Caroline ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
