My Bachmann 4-6-0 steam locomotive keeps derailing on 4' diameter brass track curves. Is there a minimum diameter curve I need to run this locomotive?
The 4 foot diameter isn't the cause - that's same radius as what comes in Bachmann's Large Scale train sets.
(a number of other Large Scale locos will not take that radius: 4-6-0 in both train set and anniversary Edition will do so just fine)
From this point
1.) examination of loco wheels and running gear is in order.
2.) examination of rail joints and rail gauge is in order.
Is it all coming off or just the pony truck?
If it is the pony truck, that is a known problem. 1st Check that the little wires aren't binding and that it slides in the slot smoothly. 2nd Adding a bit of weight on the truck frame right above the wheelsets can help as well.
If it is the whole thing, check your track joints, as mentioned. Also check your cross level and for high spots or dips.
If you're using the Aristo short radius turnouts, all bets are off...... I've never owned any Bachmann engine that liked them.
Dear Steve,
This topic has come up frequently in the past. Many fixes have been posted here.
Too, George Schreyer's tech tips reiterate what has been said here, including BBT's classic fix for the front truck.
http://www.girr.org/girr/
Best Wishes,
Jacl