Originally posted by: pcy
We use composite aluminium sandwich in teh PaQ case the "filling" is plyethelene, with (on average) 13mm serious acousticc foam inside that.
Any laminate - two or more layers bonded togeterh wit a slightly elastic glue - works well. and MDF is actually good; so a DIY solution would involve sheets of MDF and lots of doublesided adhesive tape.
65mm (or 1/4") of end grain bolsa with hevlar cloth laminated to the inside and carbon fibre laminated to the outside would also work well. Not cheap, but it would incredibly strong, very light and look stunning.