Angular Contact Bearings for Belt Driven Screws

I am looking at belt driving my ballscrews in order to contain the steppers within the footprint of the machine and to have the option of gearing down the drive on the X and Y axes. Using this arrangement there is obviously some lateral force on the pulley and therefore on the bearings too; is it necessary (or just preferable) to use angular contact bearings or will the standard BK/FK bearings be sufficient?

I've really searched but I can't seem to find a definitive answer - I'm guessing I can't be the first to ask this though.

The advice I recieved on this forum on the topic was along the lines of 'buy the best you can' which was the AC version.

BK bearings do have angular contact bearings in them, or the should have anyway. If not then throw them away.!

As a novice, what am I looking for to confirm the presence (or not) of AC bearings in my BKs?

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Originally Posted by CaptainBarnacles

As a novice, what am I looking for to confirm the presence (or not) of AC bearings in my BKs?

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Suggest you do a search for AC bearings and look at how they visually differ from standard Deep grove bearing. The visual clues when in your hand are the inner and outer races will have a thin edge and a thick edge. The inner race thin side will always face the Outer races thick edge. They will also come apart if you push on them.

Also, do a search on the forum because there's been many people show the BK bearings stripped down and will explain how they need to be assembled correctly.

Edit: Obviously if there is a number on the bearing this will ID the bearing type but often you'll not see this without stripping the BK block down.

Quote:

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Originally Posted by JAZZCNC

Suggest you do a search for AC bearings and look at how they visually differ from standard Deep grove bearing. The visual clues when in your hand are the inner and outer races will have a thin edge and a thick edge. The inner race thin side will always face the Outer races thick edge. They will also come apart if you push on them.

Also, do a search on the forum because there's been many people show the BK bearings stripped down and will explain how they need to be assembled correctly.

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Cool, Many thanks. I'll take a look.

Just pulled the face plate off my BK blocks to reveal 6002z bearings. Presumably it's possible to replace the races with quality AC ones by pressing them out? I didn't pay much for them so I wasn't expecting much but it would have been a pleasant surprise to find something better.