outside use

wooden tracks seem the way to go for external use.

How about blue tracks but cover them in aluminium foil? Glue it down and it would seal them and be corrosion free, I suppose the only issue may be if the wheels slip on it

[Super]

I suppose the only issue may be if the wheels slip on it

Would this also be a problem with the wooden rails? I would just go with the blue with no modifications. Try them for a few weeks and see what happens.

Yeah I'd just use the blue rails, my son has some 'brio' wooden track, the plarail dd51 would not run on it, the track gauge was correct but the rails were borderline be too deep, it kept getting hung up on its axle casing, it would have probable benefitted from a bit taking off the top, I also heard somewhere that brio is produce the best wooden track as it's made out of a better quality of wood than other brands,

Would this also be a problem with the wooden rails? I would just go with the blue with no modifications. Try them for a few weeks and see what happens.

trains will have a hard to go over switches and sharp curve.

Yeah I'd just use the blue rails, my son has some 'brio' wooden track, the plarail dd51 would not run on it, the track gauge was correct but the rails were borderline be too deep, it kept getting hung up on its axle casing, it would have probable benefitted from a bit taking off the top, I also heard somewhere that brio is produce the best wooden track as it's made out of a better quality of wood than other brands,

Best option I think, you probably got loads of spare track hanging around like most of us