Hi Mike,

This is the stuff used for sound deadening on car panels and the like. My friend has a garage and uses Dynamat. It is expensive.

I am looking at the weight aspects and also it is fairly easy to squirt this sort of stuff http://www.screwfix.com/p/no-nonsens...ld-750ml/45865 into a box section.

When I get to it, it wouldn't hurt to fill the gantry and frame, especially if you put in plastic tubes to run wiring. I am really looking to find out if anyone has already tried it.

Rob