I own a pair of Lipinski L-707 and the Lipinski Monoblock amps. Initially I also wanted to get a pair of their stands, which integrate the amps nicely into the stand. However, soon I noticed that their amps only ship in heights that I think will not work very well for me. I would prefer a height of about 82cm, but they only sell 90cm and 75cm. I've been writing to Lipinski what they would recommend in a situation like that, however never received any response. So, in the end I figured out that it would probably be possible to build a similar stand with commonly available components. Here are the sketches and details I have been thinking about. I would greatly appreciate any comments about my design. Probably there even are still some flaws I haven't thought about.

The design consists mainly of aluminium tubes with a diameter of 48mm and thickness of 3mm.

The bottom plate will be of 4mm thick stainless steel with dimension 300mm x 390mm. Onto this plate 5 cylinders of aluminum will be screwed (probably glued as well) on each side. The cylinder have a diameter of 40mm and a height of 100mm. On each cylinder there is a o-ring with a thickness of 1mm. It's main purpose is to prevent sand from floating out of the tubes. Comparing the diameter of the cylinders and the inner diameter of the tubes, shows that there is a difference of 2mm in total. This is mainly due to the fact, that I could not find any cylinders which would perfectly fit into the tubes. However, the sand should float around the cylinders and fill any gaps. So I don't think this will be a problem. On to the top side of the cylinder a total of 3 threaded rods per side with a diameter of 10mm will be screwed, which will connect the top and the bottom plate.

The top plate will be a stainless steel plate of 200mm x 290mm with a thickness of 3mm. The little cylinders that are attached to the plate are mainly to ensure the correct position of the tubes and will be of PVC or a similar material (haven't found the right ones with the right sizes yet). I will use a long nut to connect the threaded rod and the screws that go through the top plate. This will also allow to preload the aluminium tubes and hopefully create a sturdy stand.
Here is another pic with the tubes removed on one side. There will be a 2mm gap between the aluminium tubes to prevent any rattling that might occur.
Let me know what you think...