Doing sheet metal work are we? I'm a beginner, right in the middle of the same deal. Here is some information that may help.
I'm using the cheap Harbor Freight flux core welder, with a 600w dimmer switch wired into a 100' Extension cord. I have to cool the tack welds right after with air for about 10 seconds. I weld from the outside in, and skip weld around the panel like lug tightening on a wheel. After you get dialed in, it works like a charm. You can either use a air compressor, or a shop vac with a dimmer switch like I am to cool your welds. ;)
As a side note, I don't know which panel your fixing/replacing, or if you've sourced your sheet metal yet. My dart sheet metal is 20 ga all around (that I know of). It was put to me that 22 is usually too thin, 20 is good for bending, 18 is fine, less prone to blow through, 16 is structural. Matching the ga will usually make it easier to weld.
If you haven't sourced your material yet, take a mic, or a set of feeler gauges with you to verify thickness when you do.
Here are the numbers for the various thicknesses, ripped off from the moparts board:
Cold Rolled Steel thicknesses:
- 16ga = .0598"
- 18ga = .0478"
- 20ga = .0359"
- 22ga = .0299"
- 24ga = .0239"
Satin coat or galv. sheet
- 16ga = .0635"
- 18ga = .0516"
- 20ga = .0396"
- 22ga = .0336"
- 24ga = .0276"
Happy trails on the many, many hours of work ahead of you.
