Flangeless centre drivers in short w/b 0-6-0T - any issues?

[chris_mccarthy]

I have just realised that the prototype for a short wheelbase industrial 0-6-0T on my "to do" list has flangeless centre drivers. Any advice on this for P4, please?

I'm inclined towards CSBs for this chassis but am not wedded to that solution if they cause problems with this configuration.

I'm guessing the dynamics of a centre flangeless short wheelbase 0-6-0T may need some thought and care if the centre wheels are going to stay on the rail - or have I assessed that incorrectly? Do I just build it like a normal 0-6-0T or, say, have the centre wheels rigidly fixed (or with slight upward movement travel only) so that they can't slip off the railhead, thus the adhesion really depending on the two outboard pairs of wheels?

Or am I just taking tosh?

I wonder if anyone has built a short flangless chassis in P4 and can offer advice? I rather doubt much can be learned from the very different BR 9F 2-10-0 chassis, which has been covered in several articles etc., but I may be wrong.

Any advice appeciated. Thanks.

Chris McCarthy

[Paul Willis]

I have just realised that the prototype for a short wheelbase industrial 0-6-0T on my "to do" list has flangeless centre drivers. Any advice on this for P4, please?

Nothing to do with locomotives, but I've just lifted something out of one of my stock boxes and found this. Flange-less wheels on wagons

Misc 019 (Large).jpg

So that will be more fettling to do in the future. I'm slightly bemused as to what (apart from the obvious lack of a machined groove to hold the wheel on) has caused this.

Temperature change over recent winters? Vibration from being carted around? This was how I found the wagon, in a sealed box, so should I blame 24mm tall C&W men halfway through a job, or the mischievous activities of the OO Pixies?

Or am I just taking tosh?

Something that I am quite fond of myself!

Seriously, coming back to your locomotive, what radius of minimum curve are you expecting to send it around?

Unless the wheel is likely to drop off the edge of a rail, then I wouldn't see this as a functional problem at all. The two outer axles would provide the "steering" of the locomotive. The flange of the wheel shouldn't really be providing any "grip" to assist traction so if the centre axle is in contact with the rail then I don't see why you should lose adhesion.

Using CSBs would probably be my preferred choice as a method of suspension, for a number of reasons, but keeping the flangeless axle at the right height would definitely be one of them.

Cheers
Flymo

[chris_mccarthy]

Minimum target track radius for this loco is about 2ft 9ins.

The loco's prototype wheelbase is 10ft 3ins overall, with equally spaced axles.

Chris

[Tim V]

Paul - well known phenomenon!

The tread provides the traction and in electrically driven locos the pick up, so a flangeless driver should be regarded in the same way as the rest. In other words, it has to do some work! Your challenge will be how to remove the flange, and then you may need to look at the shape of the wheel, was it still coned, or was it flat?