new ball bearings, should i regrease them

just about to use some small ball bearings in a clock and small milling spindle. 22mm o/d 12 mm bore. I have been looking at some articals which say wash out the new grease/oil from the bearing and re grease with new, and some say dont bother, some clock guys run them dry. So whats the best option. the clock bearings will do around 1 rev per hour and the milling spindle 3000 revs per min. thanks for the help. David

If the ball bearings are new with factory grease I would not change anything, you could ask the the factory who made them. The milling spindle I have is stickered "greased for live" , sadly it does not say how long that live is. Niko.

Edited By speelwerk on 30/01/2014 14:56:04

Depends how long ago the grease was put in ! Assuming the bearings are not sealed I would washout and regrease, just to be on the safe side. Never built a clock, but i would wash out and put a drop of light oil in, unless they are stainless?

Hi David,

Open cage bearings received in our stock are considered to be packed with a preservative grease, and marked with a preservative shelf life.

Prior to installation they are washed out in a hot oil bath, then a white spirit rinse to be followed by immersion in the medium to be used when installed.

The bearing is then placed in a heat sealed bag until required for use.

It would be normal to accept that all bearings cannot be lubricated with the correct medium for its particular application by the manufacturer and should therefore be 'primed' as above.

Obviously, this doesn't apply to sealed bearings.

David,

The bearing size that you mention is large compared with what most clockmakers are using, so this may not be directly relevant ... but it's good reading anyway.

MichaelG.

I would say that for the clock bearings, a similar circumstance occurs there as with Hot Air/ Stirling Engines, if the bearings are sealed or shielded, remove the seal or shield, and remove the grease (I tend not to do this on my motors). On the other ones, if sealed or shielded, leave them, if not, grease them. Ian S C