Chipboard comes in many thicknesses , from posterboard thin to .120” , and it’s not that heavy for it’s strength and good qualities ... We used the thin stuff on our inner walls between the ribs .. and the heavy stuff for the finish panels on the front round base wall of the trailer ... screwed on with finish washers ... ( primed and painted first , of course) ... Almost 3 years now , no change ...
Here’s where I got mine ...
http://www.utrechtart.com/Search/Defaul ... d&Search=+ It’s pretty much made of the same stuff as wood is ....
cellulose ... likely From wood anyway ... easier to waterproof ... bends nice ... Likely no heavier than an equvalent canvas... and Stiffer ... whereas canvas is the tight “sock" , comparatively chipboard is the "hard skin” You might want to try a small cabinet built like that ... and the idea of feeding the machine hard skinned blanks makes it lke cutting sips, and Much easier than gluing and trimming chipboard skins after the parts are cut ... CNC should have no trouble cleanly cutting chipboard over foam eh ? ...

In the past we saw chipboard in 4’X8’ sheets ...and although we keep searching , we've yet to find a source these day... But we’ve seen some come on rolls ... although we’d need a fork lift to move it ...