Changes in v2:
- Plate width changed to .19 (from 1/8")
- Top plate thinned to 1/16"
- Bearing added in 84t gear to keep vertical shaft concentric with module
- VP pinion gear changed to 14t 3/8" hex from 20t 1/2" hex
- Drive encoder changed to E5T to fit right over the 8mm CIM shaft
- Small pocket added on module side plate
New weight is 7.06lbs per module. CAD updated on GrabCAD
here.
In making changes I realized why I needed rivets and the top bearing. The top bearing is necessary because otherwise the shaft is only constrained by one bearing in the big plate and one in the 84t gear, which can move radially and mis-align the bevel gears. By adding the top bearing, the vertical shaft is now constrained by two bearings relative to the frame and the bearing in the 84t gear will keep the module concentric with the vertical shaft. The rivets are necessary instead of gears because there is not enough room for two screw heads (and certainly not two nuts) to pass be each other between the plates of the lazy susan. The rivet heads, which are shorter, have enough clearance.