Why not use cartridge bearings in pivots?

[Chiro75]

Coming from a bicycle mechanic's point of view, why is it that no knife manufacturers use sealed cartride bearings in pivots? I would think it is due to the bearings' limitation of width, but I would imagine there are smaller bearings out there than what we use in the shop. Or is this the only reason, that a suitable size doen't exist?

 

[Tom Militano]

I saw some really small bearings at one of the knifemaking supply outfits yesterday at the Blade Show. They were selling them for use in folders. I think it was either Sheffields or K&G that had them
Tom