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Jul 17, 2023

Thrust bearing help please

Does anyone out there know of a source of proper (not too expensive) F8-16M (8 –

Does anyone out there know of a source of proper (not too expensive) F8-16M (8 – 16 x 5mm) ball thrust bearings?

Does anyone out there know of a source of proper (not too expensive) F8-16M (8 – 16 x 5mm) ball thrust bearings?

By ‘proper’, I mean that both end ‘washers’ have ball grooves in, and the washers are not identical:

This kind of 8mm hole, 16mm diameter, 5mm thick bearing (see photo) can be found cheaply from many sources and the one I have bought are made remarkably well – they can carry large axial load smoothly – but every one I have has a pair of identical washers (with 16.0mm outer diameters and ~8.3mm holes) that both want to grip the bore and both slop-around on the shaft – and therefor confer no radial location.

Oddly, when I buy F8-19M ((8 – 19 x 7mm) or F8-22M thrust bearings, made to a similar price and arriving with similar quality, I get proper different washers which go on to locate the shaft radially as well as resisting thrust – so far, at least.

BTW, some similar-sized thrust bearings have flat washers – with no grooves – and therefor have no radial location capability either, and roller-type thrust bearings at this price also have flat washers and no radial location.

The F8-22M has the same 8 – 19 x 7mm dimensions as the classic ‘608’ radial skate bearing, so beloved of home constructors. The ones I bought had the same sized ball ring as the F8-19M types, just with wider washers, making me wonder if F8-22M is a made-up thrust bearing to match the 608.

Having radial and thrust bearings in the same size allows a fully-located bearing for not-too-critical applications to be made from three cheap bearings rather than a pair of expensive angular-contact bearings or a pair of expensive taper roller bearings.