Broke the first cup. It's possible that a few times I didn't insert it right because the holes didn't line up well so I might well have begun the crack which then escalated. If it's inserted off axis it's hard to get it into position and if it even turns is very rough. Get it right and it's quite smooth.
There are several issues. First of all a tiny vertical piece of the root of the tooth broke off. I think that happened first. Then the pressure of the bearings sheared the cup along one of the print layers. So first weak spot of course the print layers and the plastic probably never really bonding past a thin line. I used 0.2mm printing. My smaller 16mm bearing is also a much higher load point than the larger ones used in the belt versions. Even if I'd made the full disk with 10 bearings I don't expect it would have made much of a difference because they just can't get as close together as a real harmonic drive with ball bearings which are also distributing the load over the entire outer race. If anything a larger group of small bearings as close as possible to each other would more accurately duplicate this. www.autoartisans.com/harmonicdrive/HarmonicDrive-11.jpg This type of flex cup if not made of metal would be better with a cross hatch carbon fibre in flexible epoxy. John _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
