Welding in patch panels

I'm about to pick up a welder and learn how to cut and weld in patch panels as i go, the experience gained here on a bud's YJ will help me with gaining exp to do some patches on my XJ's floor.

Looking to buy a welder, i'v read about a 110v Lincoln that will handle this job. Anyone have a recommendation on which model i should look at? It will also later be used for welding thin tube to add a floor in my rack,new swingaway eventually and other home fab jobs.

Were going to replace the fender and patch the tub with a clean patch taken from the fender. Do i cut the patch first then transfer the dimensions to the tub, cut it then work to fit in flush?

IIRC i'll want to work around the patch skipping around to prevent heat warpage by just using tack welds? Then grind somewhat smooth correct? Most of this patch will be behind the YJ step, so were not worried about making a professional finish. Just solid.

Here's a few pics of what i'm starting with. Appreciate any guidance.

When looking for a mig welder, compare amp ratings and duty cycle (very important). Duty cycle is what percentage of power the welder will put out after 1 minute of solid welding. My 110 welder (Snap-On FM-140A) has 100% duty cycle, when compared to the other 110 welder in the shop (Matco 140 amp/20% duty cycle) the difference is very apparent. For spotting sheet metal, either will work fine because you are not continuosly welding. But if you are planning to use for fabricating bumpers/barwork, make sure you get the most powerful one you can afford. Stay away from flux core wire and get a setup that uses argon/c02 (much better welds). Also keep in mind 110v welders are limited in the thickness of material that they can weld. 1/8 - 3/16 shouldn't be a problem, but if your going thicker than that, a 220v would probably be a better choice. hope this helps

That was alot of help...much appreciated. I wont be making bumpers or anything where i'd need 1/4" so the 110v should work fine for me.

Mind elaborating on the Fluxcore vs Argon/c02 issue? Or linking me to a "Welding for Dummie's" site or a good instructional video?

When i get a little more time i plan to search here and Pirate for welding tips threads and the like. I havent welded really since HS.

The argon is much more efficient at cleaning contaminates from your welds. I have a small flux core machine, but pretty much just use that for repairs in the field. Though I'm not the worlds best welder,but it seems to be alot harder to get good welds with proper penetration without the argon. A friend of mine bought a set of books from Jesse James (Monster Garage), and I was very suprised with the one on welding. I thought it would be aimed at beginners, but had some really good advice and equipment comparisions. I think the set was called ("how to customize anything"), or something like that. Might be worth checking out...

mig and flux core are technically different processes, but flux core, when properly set, does provide a better quality weld. you can also use flux core wire with the argon/c02 mix for an even better weld.