CAD Update - REV2 (last update11/17, fixed duct thread issue)
I made an update to the CAD and added a bearing again. Here is the complete REV2 assembly. The only changed part is the SealMount. I’ll also post links in first post above.
Reason for this update is that I am trying to minimize vibration to keep the two shaft seals alive. This time I am adding a ceramic bearing on the wet side so it is even closer to the prop for max shaft stability.
Here some history on this setup:
Frist Parker 7:1 gearbox based design. You see I had a bearing on the inside (should have kept it):
This is the second Neugart 5:1 gearbox desing (current version posted above). I removed the bearing, added a thrust bearing close to gearbox. I wanted to minimize length and was hoping the shaft is short enough to be stable:
Now this below is Rev2, haven’t printed and tried yet. You see a bearing at the very outside close to prop. I just ordered this ceramic bearing. Hope that stabilizes everything. If I would have a lathe here I would make a custom shaft with that 10mm pressfit bore for the gearbox output. These hobby shaft adapters are not the best solution but they work.

