Problems with Peco curved turnouts?

[RobertInOntario]

You mentioned that the tender drive loco only derails when passing in one direction. Which direction is that? Is it derailing when approaching from the frog end or through the points? I'm going to guess it is picking the points. It may be either a small gauge problem with the loco, or a problem with the point on the tighter of the 2 radii. If you can run it through really slow and see what is happening, you might fix it with just a bit of work on the point or a bit of a shim on the guard rail.

Thanks, Russ. I might try correcting this then by adding a shim of 8 thousandths of an inch to the guard rail. Rob