I am moving indoors and plan to build a small On30 layout. What is the preferred support platform? Plywood only, hollow core door, or???
My layout is 3x5 3/8"plywood with 1 1/2" extruded foam glued to it. You can also use a door. I used folding legs from Home Depot. IMO they are a little to low. Too much bending for me. Make sure you make your layout a conformtable working height. Also caster on the legs is another nice option. These way it will be easy to move.
Measure and cut 2X4 blocks measuring 4X4 on each side. Screw two together and glue the resulting block near a corner of the door....not the side that will face upward for the trains! Repeat for the other three corners. Glue them thoroughly, not sloppily, and let the glue dry and cure for about two days in a place where the humidity is less than 55%. If it is nearer to 60%, add another full day. Then, inboard of those blocks, screw 1X2 lengths that will yield the surface height you desire. Measure carefully, screw the tops of those lengths directly to the side of the blocks. Some glue wouldn't hurt. You should add some diagonal bracing. A 1.4" gusset of plywood at the top 'shoulder would be great, but not sufficient. Really you want to protect the lower ends from extraordinary cantilevering and splitting when a foot accidentally kicks those lower ends (which you try to minimize by placing the legs inboard of the blocks). So, measure and cut suitable lengths of the same 1X2 and make diagonal braces that run from the center of the door down to about the 'knee' area of the legs, maybe a bit lower. You may have wondered why the legs need blocking and not the braces? Well, actually, they do, but not as large. A square of 1/2" plywood glued to the center of the door will act as a stop if you but the top ends of the braces against each side. Glue should suffice for this purpose, although a tiny pocket screw driven into the block from the brace wouldn't hurt. When you invert the whole you will find that it rocks. This is due to a slightly warped door perhaps, but most likely due to a leg length discrepancy. Determine which leg is high, and file and sand it to the correct length.
