Starting 2nd Level, Thoughts on Materials Needed

I have done a second level before and you may want to go higher than 10 inches or have access openings below to get at your lower level if something derails.

I had just four 2 by 4's supporting a 6 by 4 ft. second level, one at each corner. The 5/8ths plywood should be good enuff to support most locomotives, unless you have a very large steam engine like a 4-8-4.

Lee F.

I agree with Lee that the 2nd level should be higher especially if you want to add structures. MY Korber Grain Silos barely fit. The osb board should support the weight no problem. I have used it for a second level in many areas including a tinplate section with many heavy accessories.

Bob

I have always used different levels. I use 2x4s as a frame under the 1/2" top and then most of the time I use 2x4 x 1' legs depending on the situation whether this platform is setting on another platform or not. By using 1' legs gives me about a 8" clearance below this platform. And at times I may use up to 16" legs on the very top section of rather smaller platform. One of the advantages of using the 1' legs allows me to have more of a area to work under the platform.

Paul

The flakeboard should do you fine. Our museum just added a second level to one of our exhibits and the experts used 3/4" flakeboard. It's plenty solid, and I see no reason that the odd eighth should compromise strength for a home layout. I was a bit skeptical, being a plywood partisan, but guys a lot bigger than I am were stomping around up there during construction so I'm now a believer. 2x4's every foot is overkill. Our second level uses stringers set two feet or more apart and it's as strong as you could want. 

Thanks for the responses everyone.

Wow, 2'? That would make life easier.

I'll post photos when it's done.