Flangeless Wheels for a 12 Wheel Coach

[Atlantic 3279]

Good morning all from sunny Surrey

I deal with fixed chassis 6 wheel wagons etc., by puling the wheels off Gibson carriage axles.
Then substituting a length of tubing (2mm) for the Gibson axle using superglue.
I then cut a length of rod which will fit inside the 2mm tubing, file the ends of the rod into points.
When fitted together I have a sliding axle with approx 1.5mm side play.
This works well for 6 wheel wagons etc.
BTW; this is not original thought, but picked up from this forum some years ago.

Earlswood nob (a signalbox south of Earlswood station before the line was extended to 4 track (c1900)

That should also work well. I was inclined to suggest that approach, but then I wondered how much of a skills / materials requirement might be "too much" for Jim. If that method is used, then selecting a rod that is a very loose fit inside the 2mm tube does of course also give the middle wheelset a bit of vertical freedom too.

[Jim de Griz]

A bit of an update: I've managed to improved the coach's running, but there is still work to do.

I checked the back-backs and they were a touch tight but only a little. I did a bit of adjustment and then retested.

Running solo, the most common failure mode was the front axle lifting just enough to clear the check rails as the front bogie passed through 3 way point, the immediately result being a derailment. Interestingly enough I couldn't actually 'see' that the wheels on the front axle had left the track, but it was obviously enough to cause the wheel to either miss or run up the check rail rather than follow it.

I deduce from the above that the point is not lying perfectly flat on the baseboard and that is causing either the front or rear wheels to float ever so slightly off the track with the middle wheels acting as a pivot. That would explain why removing the middle wheel greatly reduced the number of derailments, it removes the pivot so the remaining wheels remain on the track....

I tried fitting the plastic wheels I had, but amusingly they are 1mm too wide with axles 1mm too long....even cut down they just made things worse. Its a viable cause of action, but I'd need to do a better job of cutting the axles to size.

For amusement value I put in some older Hornby wheels with large metal flanges, those actually improved the running through the 3 way point immensely, but at the cost of making her very hard to drag round the 2nd radius curves....

It was doing this however that I noticed the Hornby wheels were ever so slightly smaller than the Romfords. On a hunch, I refitted the Romfords as the front and rear wheels on each bogies and for the middle wheels I used a set of old plastic Hornby wheel with smaller flanges that I had lying about. (Not sure where they came from originally, the wheels look the same as on the old Hornby Gresley Coaches, but they have a metal axle that has gone rusty and came under a Triang Thompson I brought 2nd hand)

Now the 12 Wheeler runs smoothly through the pointwork and 'mostly' smoothly round the 2nd radius, with only a little bit of stickiness through the 3 way. More testing is required, but I think she is running smoother than with the middle axles empty. That said, there is still some stickiness as the bogies go through the check rails so this might only be a temporary solution while I try others.


Anyway, I was fairly happy at this point with a working temporary solution....then I tried testing the coach in a rake.......

So, new lesson learned, its not enough for a coach to be reliable, it has to be reliable in company and other coaches follies can derail otherwise innocent coaches.

The rake is a true mixed bag, a old Hornby Composite Brake, two ex Triang Thompsons, the Isinglass 12 Wheeler, another Hornby Composite and finally an Isinglass Sheffield Stock Brake Third.

They have a mixture of wheels of varying ages (and thus different flange sizes) and different tension lock couplings. One of the Thompsons in particular has large flanges and tended to hesitate over some of my points (not the 3 way oddly enough), this would send a shockwave down the rack that tended to derail the poor 12 wheeler. I swapped the Thompsons round (until I could acquire new wheels) and now found the Thompson was being lifted up by the 12 wheeler when they were being propelled as their tension locks were at slightly different heights.....

Anyway, to cut a long story short, I've been swapping out wheels so the whole rack has small flanged wheels of one type or another. I'm also trying to adjusting the tension hooks to match, but that is proving harder. I've just broken one of the mounts on the 12 wheeler, so experimenting is paused until I get that fixed.

I'm aware that there is no sympathy to be deserved I made up that mixed rack of so many generations of my own free choice, so I'll have to soldier on and make it work! Still, it is interesting just how many little things can cause a coach to derail.

Jim de Griz

[Jim de Griz]

Good morning all from sunny Surrey

I deal with fixed chassis 6 wheel wagons etc., by puling the wheels off Gibson carriage axles.
Then substituting a length of tubing (2mm) for the Gibson axle using superglue.
I then cut a length of rod which will fit inside the 2mm tubing, file the ends of the rod into points.
When fitted together I have a sliding axle with approx 1.5mm side play.
This works well for 6 wheel wagons etc.
BTW; this is not original thought, but picked up from this forum some years ago.

Earlswood nob (a signalbox south of Earlswood station before the line was extended to 4 track (c1900)

That should also work well. I was inclined to suggest that approach, but then I wondered how much of a skills / materials requirement might be "too much" for Jim. If that method is used, then selecting a rod that is a very loose fit inside the 2mm tube does of course also give the middle wheelset a bit of vertical freedom too.

I would be very interested to give this a go, but I suspect I do not have the tools to hand to do it.

I'm assuming with the 2mm tube, I need to make a perfectly 90degree cut or the wheels won't be parallel to each other. I only have hand tools and a Dremel, is it possible to do this job with those tools, or is this a power tool and proper work bench job?

Similarly with putting the point on the rod, is that something I can do with the Dremel and a file, or do I need a proper lathe?

I'm guessing this should be brass tubing and brass axle, or would steel be better?

I don't suppose I could use the pinpoint axle off a romford wheel set (or similar set with removable wheels) and find a tube that would fit round it?

Jim de Griz

[earlswood nob]

Good morning from a soggy Surrey

I only have basic tools, and lack any engineering skill.

I use brass for most of my engineering as it's easy to file/saw/solder/etc.

I cut the tubing slightly over size and file it square. I find it difficult/impossible to saw in a straight line.

I use a Dremel and needle file to produce pointed ends to axles.

Good luck if you attempt this method.

Malcolm (Earlswood Nob)

PS Thanks Graeme, for the tip about loose axles. I've always used slugly fitting pairs

[billbedford]

Have you checked the 'top' of the point with a straight edge?

[Atlantic 3279]

That's an important point. I've noticed with Peco Code 75 Electrofrog / Unifrog points that the presence of the wire connections to the crossing can push the crossing area upwards when the point is fixed down on a hard base, if the wires are not carefully arranged.

[john coffin]

you can use both the Dremel as a kind of lathe, with some cheap needle files or a grinding wheel to obtain the pin point.

as for cutting the axles square, a mitre block, which X acto probably still be available, that would give you the
basic straight end. However, it is worth getting someone you know to provide a 2 x 2 block of hard wood, and
then get an axle hole drilled in it to the depth that you want to the overall length to be, and then you can
have a reference flat surface to file to.

Paul

[Jim de Griz]

Have you checked the 'top' of the point with a straight edge?

It is quite difficult to get a straight edge in there and lay it flat (what with all the point rodding etc surrounding the point), but I think the exit of the point is a fraction of a millimetre lower than the entrance.

I suspect that is the root of the problem....

Thank you for the suggestion, I'll add that to the list of things to check whenever I lay pointwork in the future.

you can use both the Dremel as a kind of lathe, with some cheap needle files or a grinding wheel to obtain the pin point.

as for cutting the axles square, a mitre block, which X acto probably still be available, that would give you the
basic straight end. However, it is worth getting someone you know to provide a 2 x 2 block of hard wood, and
then get an axle hole drilled in it to the depth that you want to the overall length to be, and then you can
have a reference flat surface to file to.

Paul

Would not have through of that, thanks Paul.

Jim de Griz

[john coffin]

two important points, you then have a flat reference surface,
but also try to use as big a file as possible, it is then easier to ensure that it stays flat and horizontal
to the wood.

Paul

[john coffin]

A useful trick, is to use a 12 in metal ruler, or something that wide, and hold the ruler vertically across the rails
then as long as the electricity is off(!) run it to and fro across the point.
It is worth getting a small engineers square they could be only 2 inches across, and give you a reference surface.

HTH

Paul

[Coboman]

Not sure if this is any help to you or not....my only experience with a 12 wheeled coach is an ex Dapol LMS 68' dining car by Hornby. It came with nasty plastic wheels and rode too high. After adjusting the height I fitted Dapol metal wheels and it derailed everywhere despite no other coach doing so. After much head scratching I changed the wheels for Hornby metal ones as the flanges on the Dapol ones are very shallow. Peco points do have a tendency for the curved rails to take on a slight vertical bow which seemed to be enough to allow the Dapol wheels to derail, but the Hornby ones with deeper flanges stay where they should. The coach runs perfectly now. I suspect Bachmann wheels would be just as good as the flanges look about the same.

[Atlantic 3279]

That's an interesting observation. If the Dapol metal wheels you initially tried had the same sort of flat treads (no coning) and ghastly "outward leaning" flange shapes that I encountered on a couple of Dapol wagons circa 2009 it would be a wonder if the coach could even stay on plain straight track when encountering a rail joint.

[Jim de Griz]

Interestingly enough, fitting older wheels with larger flanges solved the derailment problem over the 3 way point, but caused problems on other parts of the layout.

Jim de Griz