This is from the OP. I bought some fluid film, both a spray container and a small container with a brush for application. I have tried it on several applications and it seems to work very well. Today I built three dollies that I will use for attachments that will stay under roof but not in an entirely closed shed. I put fluid film on each of the 12 casters on the three dollies, both in the bearing races and on the axles of the caster wheels (which are in bushings, no bearings). The spray applicator isn't precise, and I couldn't get the FF directly in the bearing race or directly on the axle (didn't remove the axles), so I used a small flat-blade screwdriver to push the FF where I wanted it to go. (In the future, I'm going to have a supply of Q-tips in the shed so I can put the FF on the Q-tip and use the Q-tip to push the FF into the crevice I want it in.) Just turning the casters on their mounts and spinning the wheels spread the FF all along the bearing races (I could see the FF all around the races) and I think all along the axles. Although I don't know how the casters would have rolled without the FF, they certainly roll well with the FF. And I have noticed that FF seems to spread easily over any surface you apply it to--regardless of whether or not you actually want it to spread. I really like the product and appreciate the recommendations from you posters.