Once again we started out by looking at stills and downloading the blueprints we needed from [ GBFans.com]GBFans.com. But the site was also great to find out how most people went about constructing their own packs. We found that most people seemed to cut their parts out of wood and/or vacuum form them. We on the other hand didn't want an all wood pack because of the weight, and vacuum forming was just going to be too complicated and expensive.
So we cut our parts out of insolation foam. This stuff is very dense and very pink. And perfect in terms of weight and ease of use. Jess and I had both used this stuff while at art school (SCAD) and with a little work you can get some great results.
But we also went one step further to really get things smooth and the corners sharp by coating each piece with spackle and then sanding it down. This really is the key to getting a foam pack look like machined parts. It even leaves a very nice and subtle texture that really feels like steel machined parts.
Then by adding a couple pieces of PVC you start to really get down the shapes needed for an authentic Proton Pack.
Again Home Depot was the store of choice.
(These are obviously just a couple of the parts we made, and don't include the battery pack etc.)