Brass bearing fitting to old rtr and kits

[Richard_A]

Apologies if this is covered many times before, 

I have being building some airfix/Dapol presflo kits and I've drilled the axle holes to accept pin point bearings. When I have then fitted the axles the chassis splayes out and I can see the bearings don't go in deep enough due to the flange around it. 

 

I have ordered some flange less bearings which I hope will solve the problem. 

 

Has anyone got any tips on which bearings are the most suitable for older kits and rtr such as the Hornby tta wagon, I have bought a reaming tool from a guy on here who makes them. 

[34theletterbetweenB&D]

The flanges usually just pull off, if you are in 'want to get on with the job' mode.

 

For the splayed axle boxes problem, what I do on both plastic chassis RTR and assembled plastic kits bought s/h is to insert the bearings, insert a wheel-less pinpoint axle and heat cautiously with a  soldering iron until correcting the splay by pressure over the outside is possible. And immediately plunge into cold water.

 

CAVEAT. Not suitable for Dapol ex-Airfix kits, the plastic uncontrollably transitions to melted butter consistency.

 

 

[Richard_A]

Thank you, I'll trying pulling of the flange (the schoolboy in me keeps chuckling) and give it a try. 

[BR60103]

I don't find the flange comes off that easily. Fortunately, I have a lot of the other type. I bought a set of metric drills (hard to find here) and used the 2.0mm or 1.9mm drill. I do have a few dimples on the cover of the axle box now. 

I had the same problem with some Slater's kits where the top hat wouldn't go far enough into the hole.

 

[DCB]

Filing the point off the pin point bearing helps as does drilling the hole with an ordinary drill bit and finishing with a broken off drill ground flat across the end to give a parallel hole with no taper.

The underframe may need some additional stiffening to stop it splaying.  At least the couplings are on the same piece of plastic on Dapol kits as some other kits pull in half if you don't put a metal strip between the coupling fastenings.  Actually RCH required the same on non metal frame wagons back in the Edwardian era.

[Enterprisingwestern]

 

Easily solved, although difficult to arrive at.

If you use a Bill Bedford solebar spacer jig, that gives the correct dimension for the flush fitting of bearings, dont assume the kit has the solebars set at the correct distance. Drill out the back of the axle box and countersink it to allow the bearing to sit flush.

The problem comes when you try to find consistently made pinpoint bearings, as discussed elsewhere, experiment with various manufacturers,  (I use the H&A models variety), and then standardise on it.

I can provide photos if required?

 

Mike.

 

[Re6/6]

3 minutes ago, Enterprisingwestern said:

I can provide photos if required

 

Yes please Mike.

[Enterprisingwestern]

Apologies for the ropey phone pics.

 

 

 

Firstly, remove the moulding marks on the top of the solebar and brakegear and ensure they sit upright and square. I do this by rubbing on a sheet of wet and dry cloth.

 

 

Secondly, file the tops of the bearings flat to get rid of the tit, a 2mm hole in a coffee stirrer will suffice as a jig.

 

 

Drill the hole with a 2mm bit to ensure concentricity and then countersink the hole so that the top of the countersink is the same width as the flange on the bearing.

 

 

Here you can see the countersink hole and a flush bearing.

 

 

All four bearings in place.

 

 

Solebars glued in position. On this kit, miraculously, the spacers on the floor moulding are the correct distance apart, but have still been checked by using the BB jig. The white bits are 040" square plastic, they help align the outer end of the solebars to keep them straight, and in my case, this being an EM model, act as spacers for the brakes.

 

 

Voila, straight sides solebars.

[Il Grifone]

ForAirfix kits I always file the boss around the hole flat, drill it 2mm. diameter and then enlarge the top of the bore with a 1/8" drill to take the top hat. The use of a pin vice is advisable. With care it can even be done on a pre assembled kit, though these can usually be disassembled with care. Run the 2mm drill across the top of the opposite axleguard. It would not drill quite square, though the axleguard will usually bend sufficiently to allow this. I find setting the inside edge of the top hat flush with the axleguard is about right for 26mm. axles, but it's easy to tweak/bodge. To hide the thickness of the plastic, I then chamfer the edges of the axleguard.

Fretting out the brake level ratchets is a great improvement, but very fiddly. The mineral wagon brake gear needs sorting as well. As is, the lever takes the brakes off! It should be a Morton brake on the 1/108 version. ( Other varieties are available!)

I can't post a picture at present, but will try to remember when I get back to the UK.

Edited July 27, 2020 by Il Grifone

[5050]

I've recently had a similar problem with an etched chassis of which I built 3. One had the axleguards really splayed when I looked at it again (using Colin Waite etched units) and it appeared that the hole inside the bearings was very shallow compared to the ones on the other 2 chassis. I removed the bearings, held them in a pinchuck and drilled into them with a 0.7mm drill (or thereabouts, not critical) in another pinchuck for 1mm or so and refitted them.  The axles then fitted perfectly with no splaying.  I've got bags of assorted pin point bearings from all sorts of sources and its a process of trial and error with these and the wheels I intend using to get a perfect fit.

[Chrisr40]

I was given a tip on this which involved putting a drop of the plastic weld solvent in the hole once drilled and then pushing the bearing in to that as it will soften the plastic sufficiently to allow you to seat it up to the collar.

[Il Grifone]

There is an EMGS spec. for these bearings. unfortunately not all those available meet this. Markits have a slightly different one for example. I try to make them for the 26mm standard, but as long as they fit the wheelsets  I have to hand.

 

I should have made a record of the non-standard ones, but the only one I remember is a Hornby Dublo WELTROL MV which required either a non-standard axle length or new bogies. No-one seems to do the BR plate frame type (less holes), so non-standard axles it is. I have a second one minus bogies. In my (even more) ignorant past, I fitted it with Ratio's effort, but this is probably because it came to me without bogies). It seems a shame to waste it....

Edited March 1, 2022 by Il Grifone
Failure to make sense!

[Richard_A]

Thanks for the replies chaps, I've tried the flangless bearings and all appears to be well. I think I'll standardise on these then. 

[Fat Controller]

2 hours ago, Il Grifone said:

There is an EMGS spec. for these bearings. unfortunately not all those available meet this. Markits have a slightly different one for example. I try to make them for the 26mm standard, but as long as they fit the wheelsets  I have to hand.

 

I should have made a record of the non-standard ones, but the only one I remember is a Hornby Dublo WELTROL MV which required either a non-standard axle length or new bogies. No-one seems to do the BR plate frame type (less holes), so non-standard axles it is. I have a second one minus bogies (in my (less) ignorant past, I fitted it with Ratio's effort, but this is probably because it came to me without bogies). It seems a shame to waste it....

I had a look at the Cambrian site. They offer BR plate-frame bogies (without holes and with oil axleboxes)) https://www.cambrianmodelrail.co.uk/store/C68-BR-Plate-Bogies-oil-pair-p95280163

[Il Grifone]

16 hours ago, Fat Controller said:

I had a look at the Cambrian site. They offer BR plate-frame bogies (without holes and with oil axleboxes)) https://www.cambrianmodelrail.co.uk/store/C68-BR-Plate-Bogies-oil-pair-p95280163

 

That looks ideal!

 

IIRC the drawing of a WELTROL MV shows 2' 9" diameter wheels (just to be awkward / clear the frames), but that (apart from finding 11mm diameter three hole wheels - 10.5mmm disc are common enough and would do at a push) is not a great problem

[Mainlinefreighter58]

Has anyone tried this on Hornby RTR stuff and if yes what was the success rate like?

[Il Grifone]

I.ve never had a failure with brass or the Peco Hardlon bearings, even with axles I've pin-pointed myself. It's just a question of getting the bearing square and the play correct.

 

I've just found that Peter's Spares (usual disclaimer) not does brass bearings. There is no specification for the depth of the cone, but they are stated as suitable for 26mm axles. (I assume this is with the standard spacing of 24mm between the W-irons.) They do both plain and top hat varieties.