Request for help reducing friction and noise of a cam follower roller
I would like to ask if anyone could please help me with the following problem.
I have a small conjugate dual-roller rib or blade cam that has an inner and outer cam-follower roller working on a corresponding inner and outer cam curve. The cam curve is basically a curved "rib" with a roller on each side of the rib. The rollers oscillate about a swing arm in response to cam oscillation.
The force of the small 3/16" OD rollers is pinching the cam rib and causing drag on the manually oscillated cam. The system also has roller noise that must be reduced as much as possible. The system is very sensitive to any friction between the cam & roller, or any drag or noise in the system.
I've tried to polish the cam, and add lube, but there is still too much friction. I could also try to polish the rollers.
Is there any type of hard coating I can apply to the cam and/or rollers that will help significantly ? Any type of special lube I could use ?
The maximum Hertz contact stress is probably around 180,000 PSI. Right now, the cam is made from hardened 4140 and the roller is hardened A2 Tool Steel.
Is there any type of non-metallic roller that I could use ?
I would appreciate any suggestions for alternate materials, coatings, lubes, or anything else I might try.
Thanks for your help.