I was wondering what the best way to weld sheet metal on my truck is. I don't have a gas welder, just a cheapo wire feed flux core welder. I want to make shur my welds last, and I dont want to warp the metal or burn holes. Any tips? do I just have a low heat setting and spot weld?

 

I am using the same type welder on my truck now.I am finding a lap weld much easier to work with than a butt weld . I had too much burn through,granted I am no pro welder.I bought a flange tool so i could recess the panel to make it easier to finish.Do a search for welding. There are alot of experienced people who have their opinions and ideas here so that will be a big help.Also,practice practice practice.

 

You'll have much better sucess with you mig welder if it can be converted to gas. I tried the core wire and gave up, switched to gas a while later and have never changed back. Also use the smallest gauge wire your unit can handle, less heat buildup and less burn through.

 

The problem with the flux core wire is that the heat is so inconsistant. If you can get your hands on a gas welder you'll be a lot better off if not..... The suggestion about a flange tool is a great one, you can get one cheap at Harbor Freight. It'll not only make the job easier, it makes it look better as well.

If you have to use the flux welder, here's a tip, use a few small tack welds to hold it in place,, then after you have it shored up, go back and make short stitches, maybe 1/2 " long while going back and forth from one side to the other to help reduce warping. You won't need a bunch of welds to keep the piece in place so don't go crazy thinking you have to weld in every single inch of the patch panel.

 

Flange tools are great! I wouldnt even go as far as to make stiches. (Take no offense Indy Gearhead71, just my opinion) I have luck with just making small tacks about three or four inches apart. Be sure to switch from one side of the plate to the other to let the peice cool down. Good Luck!

 

Take a look at this thread. Try the "copper trick".
https://www.ford-trucks.com/forums/6...-wirefeed.html

 

I weld sheet metal at my job all day from 24 ga upto 1" plate. We make HVAC ductwork and other associated pieces.
Buy the Flange tool and convert your Flux fed welder to MIG (Metal Inert Gas). The conversion kit for a Lincoln Weldpack is only about 50 bucks. Use .023 wire and pic up a 40 or 80 foot regular mig bottle at the local welding supply.
If you are a novice you should also pic up a insta-flash shield Harbor Freight sells some. They have a Flaming Skull Helmet for $59.99 Item number 94566 3UMH.
The newer ones are solar powered with rechargable bateries but Ive used the same Jackson helmet with regular AAA batteries since 96. If you weld with an old style smoked glass shield once you try the insta shield you'll never go back.
Flange your patch piece not the body. Next take a Sharpy and frome the corner mark dots about 1 inch apart. Use s couple of strong magnets to hold the piec in place where clamps wont work. Making your tac welds on no bigger than a 1/4 inch long start tacking at the corners and work clockwise. After every 4 welds take a water soaked rag and quelch the welds. An oil drip pan is best for catching the drips. This will keep the panel cool and allow you to work fairly quickly. You can continue till there is no open seam but once you have put a tac every inch it is plenty strong. You could just level the welds and skim with bondo now.
John