Jim,
I will get some photos of the trucks so you can see them in action.
The pipe scaffolding has those pins you slide-in to hold the frames to the base legs that are bolted to the 2x12" planks.
Picture a "U" shaped piece of 2" steel pipe that connects to the top of the rear set of pipe racks by sliding on the 8" high piece of pipe on each side, and the rounded part of the "U" follows the front end shape of the truck. Then the welder installed two pipes down in the front of the truck right on top of the bumper frame bolts that hold the bumper on. He used a piece of 4" x 4" right angle iron that catch's the front/top bolt on each of the two pieces. And he welded two solid steel pins about 6" long on the angle iron with two holes drilled to bolt the racks on when you slide the entire front syatem on the truck. He also welded two extra pieces of steel 1/2" x 1 1/2" from the outside corner area to the sides of the front two uprights for extra support. When we first did it we could not open the hood for service with the front racks on, then we moved them so the hood will open while the racks were on.
The racks were the best design I ever came up with.
it was so cool to see 3 8-GPM rigs cleaning on a 20' long working area moving truck, instead of a scissor lift (8' feet wide).
I made the mistake and set up a new truck with the racks and it got trashed really quick. So now we get used trucks to set up this way. We also sprayed paint with the trucks and the plastic drop's did not protect everything. So used trucks are the way to go.
The next one I build will have welded pipe scaffolding base plates into the rack system, instead of bolting the base plates to the 2x12 spruce planks.
We never did any hot cleaning, only cold water on buildings. I have no truck cleaning experience.
These pipe scaffolding trucks would be killer for gents who clean trucks/big rigs. You could drive right along side the box truck on a 2 high section (Each section is 6' feet). We drove around in traffic with 2 full sections installed on the trucks, front to back, not 2 high. So it was one high and the height of the truck, say 6' feet. So from the ground to the top of the platform is about 12'. Standing on the top of the racks level, is basically right over the top of the cabin roof + 6". The entire front to back had the 2x12" planks on them permanently. So it was like 6' wide by 19' feet long from the back to the front.
I will get some pics tomorrow, I have some from a huge natural wood cleaning job and it had 3 sections high I think.
It would be hard to mass produce this type of rack system because the back section has to fit inside the pockets perfectly, to be able to get them in/out. We had to put the square pocket steel pieces in first, then place the four 2" pipe section on the top to weld it in place. Then once it was welded, we simply pulled it out. I made the inside 1 1/4" x 2" x 8" deep (Or whatever it is) steel go at least 6" inside the holes. Some people said I could just bolt a piece of steel to the top of the inside bed.
Photos are 10,000 words, soon to come. I'm so buzz'in right now, we partied all night.