The Chevy replacements for the front doors were still down to bare metal after sandblasting 2 winters ago. Surprisingly there's no surface rust starting yet. I've stored them with the other sandblasted parts in a spare bedroom with low humidity. :-)
I've painted the outside with self etching primer. I will finish scraping off the old undercoating inside the doors later.
While I was at it I coated the inside of the fin off the rear passenger side door with POR-15 and used self etching primer on the outside. The clip on holders and nuts were soaked in Eastwood's "Fast Etch" which removes the rust and leaves a nice protective zinc coating behind.
Now back to that rear door skin. This one's going to be a bit of a challenge. Due to Father Time, rust, and who knows what else, the thickness of the metal on the door skin is less than 18 gauge and more than 20 gauge. I'm using 18 gauge sheet metal for replacements which means I have to blend the seams of the replacement pieces into the rest of the door.
The bottom of the door skin has tons of pin holes and it's straight across. Hey, I can do this! :-)
First to cut off the bottom and test fit the replacement panel.
Ok, now how do I weld all the way across this and not warp it? Start off by staggering a lot of spot welds across the seam pausing in between each one to let the heat dissipate. And of course it helps if you have a nice heat sink to help dissipate the heat. The copper plate dissipates the heat from the spot weld very fast and the angle iron behind it acts as the heat sink for the copper plate.
My girlfriend told me yesterday that I was neglecting her. I jokingly pointed at the car and said "How can that be when I've been here with her all day?" Needless to say she wasn't laughing!
I'm off to the florist this morning...