Body help/advice needed

Ive tacked it about every 2 inches then I was trying to run beads between the tacks. I tried to just tack in progression from one to another but even then it will burn thru. I will let the tack cool some before tacking on the next one but I have to be very careful and slow. My concern is that just tacking will it penetrate good enough.
Rod

yes, I f heat, wire speed, correct distance from the metal and tip, and your technique. on that sheetmetal . 023 gas wire, if the old metal is eally thin, not cleaned correctly, you can have problems. practice and e xpeience will get you there.