Replacement wheels and axle bearings

The original Airfix used basically straight axles in a parallel sided plastic hole. The end points just keep the wheelset centered. The Gibson wheels are intended to run in an indentation so that the pointed end is where the load is taken. This gives very low friction for rolling while still giving enough strength. Various firms, including Gibson, make brass bearings which push into the axle bearing hole. I can't guarentee the Airfix hole will be precisely the right diameter. If not then you will need to drill out the hole to the right diameter. The best way to do that is to cut off a standard drill bit (tail end :-) so it will fit between the axle boxes and then twirl it between finger and thumb with a little pressure until the hole is the size you need it.

Regards, Greg.P.

Matt Ots wrote:

Looking at the Mainly Trains catalogue I'm a bit confused about what the difference is between the various bearings - the Gibson ones come in flanged, unflanged, waisted, 1/8th and 1/8th to 2mm reducing varieties. Then there's Romford's pinpoint flanged and pinpoint plain, Perseverance's 2mm top hat small and standard.......... all of which doesn't mean a lot to someone like me!

Can anynone shed some light on the differences here, and maybe which ones I might need to fit my Gibson wheels in the Airfix bearings?

Thanks.

Matt

"flanged" means the bearing has a larger diameter edge which stops the bearing disappearing into a too deep hole - a good thing at your stage of experience :-)

All the bearings vaguely resemble a (top) hat - the axle end runs inside the hat and the hat sits inside your (drilled out) axle hole.

Because the prototype wagon bearings are different sizes there's not always enough model material to allow a standard sized bearing to be drilled out - but you don't need to worry about that with Airfix/Dapol wagons. You just want the basic 'flanged bearing for 2mm pinpoint axles'. Swap the adjectives around or ignore them and each brand has one in it's range.

Standard OO/HO axle diameters are:

- 2mm for wagons, coaches and loco undriven wheels.

- 3mm for European loco driving axles.

- 1/8" for British loco driving axles The 2mm top hat p/p bearings generally fit into a 1/8" hole except for the exceptions.

Regards, Greg.P.

Thanks Greg. It's all a bit clearer to me now! Matt

A "top hat" bearing has a parallel sided hole and is unsuitable for pinpoint wagon wheelsets. It looks like a top hat.

Pinpoint bearings are definitely required for this application. I've never seen pin-point bearings referred to as "top hat", only flanged, unflanged or waisted. They look more like a witches pointy hat, rather than a top hat.

MBQ

wrote

Not all of them. We've got top hat bearings (which are described as such in the maker's catalogue) in stock which are clearly designed for pin-point bearings. The purpose of the flange is to limit the depth to which the bearing can be sunk into an axle box.

John.

They say you learn something new every day. That's done for today, I can go to bed now.

MBQ

wrote

Even at my advanced age I keep learning, just wish I'd time for a bit of the stuff that dreams are made of! ;-)

John.

The message from "John Turner" contains these words:

...just don't tell the wife!

"David Jackson" wrote

LOL - I think she's already gone into retirement! ;-)

John.

All the 'top-hat' bearings I have bought (from the UK) in the last 20 years have internal cones.

'Flanged' and 'top-hat' are the same thing as far as I know. 'Waisted' OTOH have the external body of the bearing in two different diameters, made particularly for wagon axle boxes that are smaller than the normal Airfix BR for example. The ones I have in my bits box have flanges and are intended for pin-point axles. The only (2mm) bearings I have that are not intended for pin-points are some old Peco pressed brass ones. (still in catalogue)

Regards, Greg.P.