Another post on these!!! I built the TP blaster from plywood that they have plans for. I used angle iron for legs, now they show more wood in pix for that. I used their components, they have a kit for it. I Did later make the window come open on hinges to put the plastics on and sometimes to put a part in, but use side door mostly. I also used expanded metal for the floor and sheet metal on the back and left side to keep wear down. It IS wearing into wood, but has lasted years so far. I have 6 hp 80 gal presser and it runs constant when blasting, I have to let it rest some times on bigger parts. I made mine the full 48" width of the plywood, tho plans show smaller. Didn't need anymore wood to do that. Oh, yeah, also cut the window 1 x 3 witch is bigger then also. Two spots, one each way for a light, flourescents don't light enough. Things wear out, tips, gun parts, plastic over glass inside, even the hoses and pick-up tube have all been replaced at one time or more. I use their Carbide tip kit, about $50 when on sale, lasts real long time, compared to reg steel or ceramic ones. I put mine on wheels to move outside on some "cleaning days" for it and can blow it all out then in driveway. You DO have to do that sometimes.
I also just bought a HB one from a show just for heck of it. Gun hoses not as long or nice, the light is useless, rest seems good. It Does leak at every joint and should be caulked before use or seal between the joints as built. I didn't, the instructions said nothing about it, but is needed. It's window is real small, hard to reach in side door to put on plastic. Window is bolted in with nuts, so not easy to remove to put it on. I'm going to change that and make it a quick remove item and bolt from outside only this summer. Might even make that one swivel up to change plastic easy.
One final thing.....they always plug or have trouble and can really P*** you off at times! Have fun!