Just got my second engine of this type. First one ran flawlessly at all speeds right out of box. Second one derailed quite a bit. First fixed wire comeing out of tender that vwas slightly out of place, no change. Next bent drawbar up slightly to more match other, improved but still a problem. Next checked the track as now it only derailed one place, everything was in gauge, no solder melt there from feeders etc. Now it runs great though but wonder if it is because I broke the engine in as I did not really do anything to the track.
I find that my steam locos sometimes derail a few times after sitting on a shelf for a few weeks. They seem to need a bit of warm-up time. I suspect that the idle time affects the side-play of the drivers. A bit of oxydation on the wheels and picks-ups might also create a bit of jerkiness. Both problems seem to go away after a few minutes of running. Perhaps the gurus of the forum can confirm.
Simon
I do remember that on the other one I started the test at slow speed and started with the high speed on this one, guess I was trying to get the breakin done quickly. Now I have two other engines to try out, as time ran out yesterday, not the same type engine though.
If you got a wheel gauge try checking the wheels to see if they are in spec. Also if the front has a spring for the leading pilot wheels try a stronger spring to keep the wheel on the track.
Please describe the derailments. Which axles, locomotive or tender, both? And where on your track system?
Ended up only having derailments in middle of a turn. I copied everything on this enginne to match first engine and that got me to derailments only one place, on a curve and nothing going on, not even a feeder. Ran it a bunch more and then all of a sudden, no more derailments. Like I said it could have been a slight budge when checking gauge but the track is caulked down so that is unlikely. Like I said it runs fine now but you never know.