Re: Safari Rack Flooring
I like you idea of using E Track on the floor of the rack, maybe 3 or 4 running side to side and some 2" straps to hold things in place.
As far as the floor material goes:
1) Aluminum sheet will need quite a bit of support if you want to walk on it and could make quite a racket in cross winds. It will also react to mild steel and literally disappear over time and sometimes paint alone will not prevent this reaction. Stainless fasteners need to be used along with a good barrier between mild steel and the aluminum. It will also need support around the perimeter, if you want to minimize cross wind noise and maximize rigidity.
2) Expanded metal is not very ridged and when mounted horizontally, it will sag between supports. If you bolt it down, it will stretch and elongate the holes. It will also need support along the outside perimeter. The paint will wear over time leading to rust and rusty streaks running down the side of your van.
3) My preference would be 3/4 or 1" marine grade plywood. Easy to cut and shape, will not rot or rust, accepts paint very well, economical and low maintenance. Very rigid as well. When I get around to my roof rack, that is what will be used along with some Van Tech ladder racks.
"there is neither science nor fact prevailing here" - vlamgat