Model Railway Forum

Hello all,

I recently bought a s/h ready built DJH kit of a BR Standard 4MT tank. As can be seen, it's been built/weathered to a good standard and I'm really impressed. There's a problem though which I hadn't thought through before buying it - there is an area of uneven track on my layout that coincides with a curve of 3rd radius that I cannot make flatter (difficult to explain). The engine has zero float in its axles/bearings and so derails every time. I can't see a way to give the drivers any float.

Is this something others have encountered and have you found a solution?

Thanks for any input.

Presumably the loco runs perfectly elsewhere on the layout? If so, the derailing is a symptom of an underlying fault related to that specific part of the track.
It may be more challenging but it's always best to treat the cause rather than the symptom.
Maybe post some pictures of the 'tricky track' - someone on here may have a solution.

Steve M wrote: ↑Tue Aug 06, 2024 12:10 pm Presumably the loco runs perfectly elsewhere on the layout? If so, the derailing is a symptom of an underlying fault related to that specific part of the track.
It may be more challenging but it's always best to treat the cause rather than the symptom.
Maybe post some pictures of the 'tricky track' - someone on here may have a solution.

Thanks Steve, I think I may have found the problem. I hadn't noticed before, but there's a slight shallow on the outside rail and I think this is allowing the leading driver to derail as the chassis has zero flex. I'm going to let a new bit of track in there and see if it helps. TBF, it doesn't like the 3rd radius much either. I can see me selling it on perhaps or use it just as the station pilot which has no tight curves.