Two 2 x 4 grid sections have been completed. The2 x 4 L-girders made earlier were joined by short L-girders into a grid. After finding that the first, which had yellow glue and wood screws at all joints, made distressing cracking noises when 'tested', I switched to Liquid Nails for the small-area joints, and started using drywall screws at all joints, having run out of wood screws. Both units seem extremely rigid against bending and racking stresses; twisting is decent but not perfect. There has to be a way to make a light model RR frame that won't twist! Maybe I could try some 1 x 2 cross-bridging...
Having put aside the question of legs, I am now pondering my options for topping these units. I want a flat top, lightweight yet rigid, cheap to build, with all fasteners from below, and of course /quiet/. What does everybody think about:
-1/4" plywood or masonite glue-laminated to 2" foam- the board holds the screws; the foam provides rigidity, and can be sculpted. Track would be laid on cork roadbed. Cost, probably .75 per square foot. I could also use just foam, at .50 per square foot, but would have to glue this, which I'm trying to avoid.
-3/8" or 1/2" plywood or waferboard with1/2" Homasote glue-laminated to it. Track would be directly laid on the Homasote. Not so easy to sculpt, perhaps, and a bit more expensive, at $1 per square foot, but perhaps quieter and stronger? Certainly it would hold nails better.
For this section of board, since it's going to be a flattish industrial area with a number of spurs, I'm not going to bother with open-grid work. If I use the Homasote-plywood method I may well space the board out 1" or so, though.
Has anybody some suggestions or favored methods I might try here?
Cordially yours: Gerard P. President, a box of track and some grids.