Hi everyone,
I would like to ask if anyone could please offer some advice on the following...
I have a cantilever mounted round steel housing about 1.5" long that I want to oscillate on a 3/8" OD hardened steel dowel pin. I plan on just pressing a bushing material into the full length of the housing, and then drill & ream the bushing ID to fit over the dowel pin. I need the clearance between the ID of the bushing and the OD of the dowel pin to be as small as possible. I can only lube the bushing once at assembly and then never again.
I would prefer that the maximum clearance between the dowel pin OD and the bushing ID is not over .001" but I may be able to get away with .
002". I would like to use a high pressure grease to lube the bushing and shaft, but how small can my clearance be before it won't allow the grease to go and/or stay between the shaft OD and the bushing ID, or before the low clearance defeats the lube somehow ?
The housing is just oscillated by hand intermittently. Any recommendations for a bushing material, bushing ID surface finish, and lube, would be appreciated.
Presently, I have no choice but to press some bushing material into an existing housing, but in the future, would I be better off making the housing itself out of some pre-hardened 4140 and then using the housing itself as the bushing material ? Would this wear much better than a bronze bushing ? Would non-hardened 4140 or non-hardened tool steel wear better than bronze ?
I would like this thing to last as long as possible before the clearance opens up too far. I also think I need to stay with a bushing and not a rolling element bearing.
Any advice or personal experience with bushing materials, loads, and estimated wear rates would be appreciated.
Thanks John