Atlas Master Engines derailing in curves

[Anonymous]

Hello all. I have been model railroading for 10 years (and real railroading for 12) and I am stumped with a problem. All of my master series engines (2 gp40's 1 gp38 and 1 b40-8) are derailing in curves. I have several P2k and Kato engines and have no problems with them. The derailments (always the lead axle) happen in relatively gently curves and always when under load. When running the engines lite they don't derail. As I said, I'm stumped. Any help will be greatly appreciated.

Thanks in Advance,
Jim

[cmrproducts]

Do all the usual things like checking wheel gauge and side to side movement of the wheel sets in the truck assy. and the movement of the truck (they sometimes are a little stiff)

Then check the track gauge (again)

Place the engine on a flat surface and see if all the wheels on the truck assy in question are touching. It could be that truck assy is twisted a small amount and this will make the one wheel want to climb the rails.

BOB H Clarion, PA

[Anonymous]

Thanks for the reply. I'll try and see what happens

[selector]

I think that bob's advice is excellent. You might also consider that, under load, the rear (attached) ends of the loco(s) are essentially pulled on an axis back along the track axis behind them (i.e.-the rolling stock acts as a directional drag). This has the effect of keeping the front end less able to guide itself around the curve if there is a restriction to the range over which the front truck can pivot. I had to modify some Harriman pax cars for steam because they did not like to negotiate 22" radius curves when everything else on my layout was content with that curvature. The cure was to cut away (gasp) some restrictive under-steps plastic to give the truck another 3-6 deg of freedom. It seems to have done the trick.

[nslakediv]

go to atlas website and check out the section on FAQ, they had a recall on some of the trucks on the GP's. Dash 8???? maybe track is slightly depressed.