RedEDGE2k1,
Stronger: The mechanical properties of standard sheathing grade plywood and douglas fir are approximately the same at ~4000 PSI tensile and compressive strength. That being the case, a .75" thick piece of plywood 3.5" wide has the same characteristics as half of one "2X4" of the same length. SO, your contention that the stand would be stronger only fits as long as there are no holes cut into the panels. Now, I don't know about you but I need access to my sump. Therefore people will need to be careful about the size of the openings in the stand to ensure they are strong enough. In fact, while a 2X4 top span can easily support a 75g tank, you would need the plywood under the top to be at least 4.5" wide to have the same strength. So therefore the perception that plywood is stronger then the solid wood stand is conditional.
Faster: That depends on what tools and help one has available to them. For one, how do you hold the side panels upright so you can pre-drill the holes? My original design allows for clamping pieces together or to a carpenters square for easy pre-drilling and tight assembly. Also, how do you cut out the holes in your panels? A drill for a pilot hole and jig saw with guide is one way. A router and guide is another. For mine, a pilot hole and then a counter top edging bit in the router uses the frame as a guide and gives you openings as big as the legs. I would say they are even in time of build.
Easier: In terms of figuring out sizing to get strength I would say the solid wood is easier to size as its in known steps. Overall, I would like to hear why you think your plan is easier? Fewer pieces surely but the panels seem harder to assemble to me.
Lighter: Absolutely. I won't argue there.
Cheaper: That depends on the quality of materials. Thinner plywood is less expensive and 2X material is easy to come by where as quality A face plywood can run a pretty penny. If you screw up the plywood you may have to buy a whole new piece where as mine can be faced in strips as several folks on RC have shown. It all depends on the final look.
schristi69, the whole panel transfers the load only when it is left intact. If the sump is located under the tank, an opening of some kind is need and this will degrade the strength of the stand.
To all those who wish to pursue the panel stand concept, please go for it and keep us posted. It is my opinion that all ideas are worth a good look.
