Quote:
Originally Posted by nathannfm
For the shafts you might try ceramic coated aluminium shafts from McMaster they have a surface hardness much higher than the steel ones you are currently using and being aluminium are lighter and even easier to machine.
As for the thrust bearings since the inner race of the ball bearing, the miter gear and the shaft should all be spinning at the same speed I don't see where friction comes into play. I was wondering if anyone knows a way to calculate the force along the axle that would be applied to the inner race of the ball bearing by the back of the miter gear if the thrust bearing were not there, and if this would be enough to damage the ball bearing. I understand that with the thrust bearings being as inexpensive as they are it can't hurt to have it, but I was curious if calculations could be done to prove its worth. |
My team used a modified 1640 design this year.
They use a pair of needle bearings when the bottom needle bearing sits in the co-axle. The thrust bearing is there to stop the top of the miter gears from contacting bottom of the co-axil during operation and to insure that the miter has a clean contact with the outer miter gear. -top miter
The bottom miter gear and its thrust bearing is there to deal with the axial loads that are produced by the miter gears. Thus increasing mechanical efficacy and allowing the module to run for long periods of time with out damage. (long ie a season)
The idea of the ceramic shafts do not sounds like the best idea hey seem like they might shatter under heavy impact. my two cents.