MTH Realtrax layout on the patio

I think there likely will be issues with both moisture and temperature changes over time, but good luck.  A tarp can prevent water damage but won't affect humidity or temperature, unfortunately. I don't know that there are O gauge tracks designed for outdoor use, as there are in large scale.  Would be interested in hearing ideas about this.

I have a portable layout stored in similar conditions with Stainless Gargaves and one small loop of Realtrax (mix of solid and hollow rail).  Both have held up well but there are a few things to point out.  While the gargraves I used were stainless track, the pins were not. I ended up replacing those a few years in with a stainless alternative from a hardware store.  Realtrax & Gargraves plastic is not UV resistant, if you plan to have any of this exposed to sunlight, you can get UV-resistant spray that you'd need to clean off the top of the rails after you apply. I'd suggest applying some die-electric grease to the copper connections under the RealTrax where corrosion is most likely to occur, I haven't experienced this but if I ever pull up that track I'd do it just to be sure. I also soldered the small jumper wire between the two outside rails (of both systems) occasionally to ensure both outside rails have a solid connection and are not dependent on train wheels.

Thanks for the replies. I will update everyone in the spring after it goes through the first winter.

Bob