How tight should a bearing race be?
Bearing races are designed to have a friction fit inside a housing. The tolerance between their sides and the opening in the housings should be so tight that races are held firmly in place while the bearing turns freely inside them. Firm strikes on the back side of the race will pop it out.
When do you need to replace a bearing race?
But there are times when a replacement bearing race — even when it’s exactly the right replacement — just doesn’t fit snuggly enough in the housing.
Why do bearing races need to be tight?
Bearing races are designed to have a friction fit inside a housing. The tolerance between their sides and the opening in the housings should be so tight that races are held firmly in place while the bearing turns freely inside them. All wear then occurs between the race and the bearing, protecting the larger housing.
What happens when you punch in a bearing race?
As the point of the centre punch is pounded into the housing, it displaces some of the metal and pushes it up above the existing surface, creating bumps. What that does is effectively reduce the diameter of the opening in the housing, restoring a friction fit.
What to do with a loose bearing race?
All wear then occurs between the race and the bearing, protecting the larger housing. Getting an old bearing race out of a housing is a simple process. Usually, a hammer and punch is all that is required. Firm strikes on the back side of the race will pop it out.
What happens if a bearing race is too loose?
If a race is too loose and there isn’t enough friction to hold it tight, it could turn in place with the bearing and eventually damage the housing, which means a really expensive repair bill some time down the road.
Why are needle bearings pressed into aluminum hubs?
Because those needle bearings are prone to disintegrating, allowing the axle to saw itself apart against the hub, whoever made these hubs engineered in proper roller bearings in their place. The races for those bearings were pressed into the aluminum hub, and I would have been happy to leave them there, except that they were too pitted to reuse.
As the point of the centre punch is pounded into the housing, it displaces some of the metal and pushes it up above the existing surface, creating bumps. What that does is effectively reduce the diameter of the opening in the housing, restoring a friction fit.
What should be the tolerance between the race and the bearing?
The tolerance between their sides and the opening in the housings should be so tight that races are held firmly in place while the bearing turns freely inside them. All wear then occurs between the race and the bearing, protecting the larger housing.