Bearning pinch? An engineering question

Warming a housing can aid fitting but if the bearing has low internal clearance and the outer ring has too much interference, it will tighten up as it cools anyway. As Comnoz says, you need a C3 bearing (or UK equivalent). There's presumably a DIN standard for European bearings.

I think that you need to go back to the bearing supplier, explain the application (that it will be interference fitted on the outer ring but not the inner) and ask them to supply the correct bearing.

If you bore the housing until there is no more interference then you'll end up with it spinning. It has to be a tight fit even when cold.

splatt said:

I'm going to ask, how much interference?, how round is the hole?

Click to expand...

You know...I'm starting wonder if the hole is round? :shock: :?

I've just emailed Schaeffler to find out whether that FAG bearing 4203BB.TVH has the C3 designation.

When I hear, I'll let you know.

The DIN and ISO std are the same so C3 means the same thing both sides of the Atlantic.

If the bearing bore in the hub is really 38.97 mm that's way too small for a 40 mm bearing. I expect something like .01-.02 mm smaller than the bearing would be right.

It's unfortunate that something is wrong with your new hub (not the first time a new part has been 'off' but at least they're being manufactured). I installed the Slovakian bearing in my original hub and the Freeze/Heat trick worked a treat. I was shocked at how easily the bearing dropped in.

Hi Guys,

Just a quick note for anyone who's interested, that is the 4203BB.TVH bearing does have a c3 version. Tho none are in stock...and none planned for production. I got that from the Schaeffler engineer.

Thanks for putting up with my griping.

Steve

A friend of mine who works for a SKF branch told me that SKF use C3 as their standard clearance