Swerve drive questions

[asid61]

Originally Posted by nathannfm

I stand corrected, McMaster recommends not using bearings where the balls/rollers contact the surface of the ceramic coated shafts.

Any reason why? Point contact?

[nathannfm]

Originally Posted by asid61

Any reason why? Point contact?

I actually emailed them about it:

Originally Posted by NathanNFM

I was looking at your ceramic coated aluminum shafts (1031k71) and saw the Note: "Note: Ceramic-coated aluminum shafts are not intended for use with linear ball bearings" and was wondering if you could tell me why this is the case? I am looking to use them with a needle bearing (5905k132) at no more than 6000 rpm, would this note apply in that case as well?

Originally Posted by McMaster

The manufacturer of this shaft does not recommend it for use with needle or ball bearings, as they can damage the ceramic coating on the shaft.

[Gdeaver]

If you go to the Igus web site they have info on using AL anodized shafts for use with their sleeve bearings. Igus supports First and we have used their bearing and anodized shafts many times. Make sure you find read and understand their comments on sticktion with plastic bearings. Chrome coatings tend to delamenate- flake off with point contact loads. Hard anodizing works.
You don't have to use the ball thrust bearing on the transfer shaft but if you want a low friction durable solution use them. Let the thrust bearing handle the axial loads and the ball bearing handle the radial loads. We have looked at that vertical many times and keep going back to steel and needle bearings.