Next question - ABS Caravan contruction, why not?
 

With 3D printers being all the rage, and with ABS plastic being very recycleable, why aren't vans built this way?

Forget the silly wooden batons and aluminium stucco - print the entire caravan from ABS plastic! It could be any colour you like, any shape you wanted, and 100% waterproof. No seams, no sealant, just a rigid structure fabricated from one piece of ABS.

Good idea, no?

Most new caravans are wood free and have been for a number of years so no problems with rot due to water Ingres.

As regards the printers does anyone make on big enough?