January 3, 2022 9:54:10 AM CET John Dammeyer <jo...@autoartisans.com> wrote: For fun I created Todd's version with 0.5module gears. The OD of the assembly is now 60mm compared to 150mm. It would now be possible to choose a far east harmonic drive tapered roller assembly to hold the driven gear in place. Although they are expensive.
Not sure what type of bearings, if any would be used for the planetary gear clusters. I suppose one could press in bronze sleeves. I guess it all depends on the duty cycle and target application. If it's a 6 axis robot arm used for tool changing and placement/removal of milled parts then it's not running continuously. Might well for the home or small shop be more than adequate. This example still has 67.3333333:1 reduction but if the fit is well set then the backlash is essentially zero which is different from normal planetary reduction drives. Not sure how important that is for a 6 axis robot arm. In either case, using a 4th axis to create all three spur gears at the same time (one set of 40T and one set of 41 T) and then some sort of broaching/indexing to create the two ring gears the real issue is the outer bearing of the 101T output ring gear. But overall not that difficult to create once you have the 0.5 module shaper style cutter. John Where can I find more info about Todd's planetary drive. It looks very familiar. _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users