Re: [CAD_CAM_EDM_DRO] Re: Helical Couplings

Doug,

Yes, helical will wind up. Torque them too hard and they will
permanently deform. I bought a batch on eBay when I first started
lurking there. Got one with two of the helical beams broken, and another
with all three beams deformed. (Still made out great on the remaining
good ones!)

Bellows type will not take great torque loads either. If I had to direct
couple a servo motor, I'd spend the bucks for dedicated servo couplers
which have two hubs and generally a floating middle hub, and use
specially shaped sheetmetal plates to connect everything together. They
are fairly tolerant of axial misalignment, but not very good for radial
misalignment. They also cost hefty bucks.
If I ever decide to try to servo my Millport, I'll just make some
brackets and go to belts. (gettin tired already of banging various parts
of my anatomy on the direct coupled stepper motors...)

Jon