Bottom wood sections are cut and installed. The extreme bottom piece (We'll call it the "floor") is simple sanded 1/2" plywood. In order to fit it, I ripped it down the center, braced it underneath with a 2x3 and secured it well by drilling the steel tubing and screwing the whole mess down! It supports my weight, standing directly in the center of it. It is only going to be used for storage, etc...so we're "good-to-go"!
The next 2 sections up are simple wooden flooring underlament, about 1/4" stock. They will only be used to glue background material onto and no structural strength is really needed. You could use utility board (black or white) from Stales, etc. "BUT" (Had to get one in there) this stuff is $12.00 a 4" x 8" sheet. I get 3 sections out of it and the utility fiber boards run $5.00 each!
The next 2 sections are more 1/2" plywood as they will, not only hold background material but also Randall knives or whatever else I am photographing. I just feel more secure with a little more substance to these. Other background boards or material, layed on these loosely, will equally share this support.
....more to come, Capt. Chris