[HO455]

Picking back up where I left off in post 678. I want my rebuilt seat to have a taller back so I am cutting 2 backs to make one. First step was mocking up where I wanted to be. Which was 3.5 inches higher than factory.
It was important to make the cuts low enough on the bar to avoid the deformed areas below the 90 degree bends. It is important to be able insert a piece of tube inside to strengthen the weld joint. I also thought it better to have the joint as high as possible since there would be less leverage on it than there would be at the bottom.
After deciding where I wanted the joints to be I added an extra inch in each direction just in case. I took my 9" grinder with a cutoff wheel and had things apart in no time.
My caution in the layout paid off immediately when I looked at the cuts. For some reason there are tubes installed inside the tube frames. (Photo #2) They seemed to be in the bends and at the bottom where the flattened bends are. (I have to admit I didn't spend a lot of time examining them.) I was lucky in that I only had to adjust the location of the joints by 1/2 inch to be clear of the inter tube.
Once I had ground the ends square, I cleaned up inside the tubes with a file to allow my stiffeners to fit. The ID of the tubing is just over 7/8" which isn't a real common OD for tubing available on a Sunday afternoon. Fortunately I managed to scrounge up two 1 1/2" long spacers, which I feel will work fine but I really would have liked some longer ones.
I drilled some holes to allow me to plug weld the spacer to the tubing as well as the weld at the joint. I'm shooting for a 1/16" gap between the upper and lower tubes that will allow the weld to penetrate all three pieces.
My spacers may look a bit rough but that came from grinding the galvanizing off so I don't poison myself welding it up.
The rest of the afternoon was spent removing paint and rust from all of the wires on the back that will have to be welded.
Oh and I ground down the ends of all the wires where they are welded to the frame. Every one of them had poked through the upholstery. (The last photo.) I want to avoid that in the future.