October 1, 2022
  • October 1, 2022

Thrust bearing help please

By on September 16, 2022 0

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

By “correct” I mean that both end “washers” have ball grooves and the washers are not identical:

  • the center hole of a washer fits snugly against the shaft, while its outside diameter is loose in the bore, while
  • the other washer is loose around the shaft, while its outer diameter fits snugly in the bore

This kind of 8mm hole, 16mm diameter, 5mm thick bearing (see Photo) can be found inexpensively from many sources and the ones I have purchased are remarkably well made – they can handle heavy axial loading smoothly – but each one I have has an identical pair of washers (with outside diameters of 16.0 mm and holes of about 8.3 mm) which both want to grip the bore and bow on the shaft – and therefore confer no radial location.

Oddly enough, when I buy F8-19M thrust bearings ((8 – 19 x 7 mm) or F8-22M, which are made at a similar price and come in a similar quality, I get different suitable washers that help locate the shaft radially as well as resist thrust – so far, at least.

BTW some similar sized thrust bearings have flat washers – no grooves – and therefore also have no radial location capability, and roller 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 popular with home builders. The ones I bought had the same ball ring size as the F8-19M types, just with wider washers, which makes me wonder if the F8-22M is a compound thrust bearing to match the 608 .

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