49shep, Too bad you're on the West coast. If you were in Maryland, Robert (MPandC) could fix you right up. My mom lives up the coast just a bit from you, and I get by there every year or so, and could help out. But you probably don't want to wait that long.
You said you were using many bottles of gas. Are you using Oxy-Acetylene or MIG for your welding?
O/A takes a lot more skill (at least in my experience) to get a good weld.
Each weld spot shrinks a bit as it cools, and pulls the panels together. Robert has demonstrated how to get the right amount of planishing by welding a sample with two dots, and observing how much the gap shrinks, then planishing till it's back to the original gap. He may have a link to that in the thread I linked. It's well worth reading every word of it and looking at all the links he posts.
