Welding 101

general_lee_jr · Post by **general_lee_jr** » Wed May 05, 2004 11:21 am

Is their anywhere you can go to read up on welding sheet metal. I just bought a 110v welder but am afraid I will ruin everything I touch. Any advice would be great. Thanks in advance

JC-ATL · Post by **JC-ATL** » Wed May 05, 2004 11:40 am

I'm sure there is, but the best way to learn is to take a class. North Metro Tech in Acworth offers a basic welding class for cheap. The rest is practice.

Terry in TN · Post by **Terry in TN** » Wed May 05, 2004 12:01 pm

If its a 110 MIG welder that plugs into a wall outlet of a house its duty cycle will be something like 10%. That means you'll be able to weld a bead about a foot long and then wait till the welder cools down to weld some more. You'll know when its hot because it will not want to start to weld. It will just want to strike sparks and stick to your work. MIG welding is easy. If your using wire without flux then you'll use CO2 gas or combo of an inert gas to shield the hot weld from atmospheric oxygen. You should have a dial for how fast it feeds the wire and one for how hot or powerful you want the it to penetrate. Keep the area your welding together clean of rust and paint which makes it hard to get it to arc and the fumes from paint and especially galvanized metal will make you want to vomit. On welding itself run the tip over the object like your trying to strike a match and try to end up a few millimeters off of the object. This is when your trying to establish an arc. Then just keep moving the tip a little at a time to avoid punching a hole or building up too much material. If is sticking to your work and the tip gets stuck a lot turn up the wire feeder dial or turn down the power dial until you can sustain an arc well. Stitch welding works best with these welders. Work on a half to one inch length of weld at a time at different places. For example your welding a 12inch section of panel you want to make a stitch at the center or at one end and then go to the opposite end and stitch. What happens if you just work from one end to the other is that the metal shrinks and pulls the opposite end together and messes the alignment of the two pieces. Stitching helps keep the welder cooler too. If your doing anything but just a short bit of welding cover any exposed body parts from the ultraviolet light coming from the weld. You will regret it if you don't. I hope I've helped. Its a pretty short learning curve for the basics once you get to working with it.

general_lee_jr · Post by **general_lee_jr** » Wed May 05, 2004 2:47 pm

I think this weekend I am going to buy a sheet of 18G and cut it all up and build a bunch of little boxes to practice with.

Searoy · Post by **Searoy** » Wed May 05, 2004 3:05 pm

Are you using gas or flux core? When welding sheet metal of any thickness I always use the small .024 wire with Argon, or at least mix. Straight CO2 welds too hot for me, and flux core welds MUCH too hot. I prefer to turn my current up as it is to get flat welds, but with CO2 I can't slow it down enough, and flux core, well, I don't use flux core on anything less than 1/8" plate.

As for welding on a short duty cycle welder, I rarely have a problem. I still weld sheet the way I was taught, a spot at a time, slowly and spread out. The idea is to hit it hard and fast with a hot spotweld for a flat and deep weld, but short enough that you don't have a large heat mark. Keep the wire speed up quite a bit as well. Then move several inches down the seam and put another. Continue stitching wide gaps like that all along the seam. Then when you are done, if you can touch the first spot with a bare pinky finger and hold it there comfortably, you can weld another spot in that area, between your first 2 spots, etc. and so forth until you have stitched the whole seam together and your thousands of spotwelds overlap sightly. By welding this slowly you not only reduce metal warping, but you don't put your welder against it's duty cycle limit.

Build a miniature set of stairs, like mouse size. That will show you how you warp the metal as you weld. Cut all your steps the same size and begin welding at the bottom step. If you can't line up the top step well when you get there, you have put too much heat into the metal and warped it. That would represent body panels you then must straighten out before oyu are done.

general_lee_jr · Post by **general_lee_jr** » Wed May 05, 2004 4:06 pm

Thats cool. I will give it a try. All I have is the flux core. I look forward to learning. I went to the looking on the internet today and found a whole bunch of stuff I need to read.

Max Welton · Post by **Max Welton** » Wed May 05, 2004 5:01 pm

If you have a auto dismantler nearby, they may give you a mangled fender for cheap. Take it home to practice on.

general_lee_jr · Post by **general_lee_jr** » Wed May 05, 2004 5:28 pm

I wont have to go very far for that. I am sure I can find something in my garage that should be in the junk yard!LOL

Hank Winning · Post by **Hank Winning** » Thu May 06, 2004 7:24 pm

I've been real happy using our Lincoln 200amp MIG with shielding gas and .023 for the body work and .035 0r .045 for the rest.
Those MIGs are great I should have bought one 20 years ago

I've Never tried flux core wire.

Try Using the 1/8" drill putting holes every inch and using sheet metal screws every other hole to pull it all together.
fill up the holes-
Remove the screws and fill up those holes backing up the holes with a flattened copper pipe

We have a air tool adapter that hammers a step in the sheet metal to hake a flush yet overlaping joint . real strong

Then Start saving your pennies for a Plasma cutter

have fun
hank

general_lee_jr · Post by **general_lee_jr** » Fri May 07, 2004 10:25 am

I am going to weld something this weekend. I just dont know what yet. I am going to the library today and check out some books to read and study.

Kafer_Mike · Post by **Kafer_Mike** » Fri May 07, 2004 10:45 am

If you haven't already, read John Kelly's article on welding...

http://www.type2.com/library/body/wlsh.htm

JC-ATL · Post by **JC-ATL** » Fri May 07, 2004 10:51 am

Hank Winning wrote:We have a air tool adapter that hammers a step in the sheet metal to hake a flush yet overlaping joint

Hey Hank, what's that thing called, and where did you get it?

Kafer_Mike · Post by **Kafer_Mike** » Fri May 07, 2004 2:45 pm

It's a panel flanger attachement for an air chisel. Try one of the online tool houses like Harbor Freight...

Searoy · Post by **Searoy** » Fri May 07, 2004 5:08 pm

The bad thing about that kind of overlapping welded connection is, if oyu warp the metal, good luck getting it back into shape.

Butt welds all the way.

Honda's Killer · Post by **Honda's Killer** » Fri May 07, 2004 5:37 pm

LOL he said "butt"
I know the flanger you talking bout. On the other side it has a "hole" maker. There nice. $40 harbor freight. I use it ALL the time.
Im a crappy welder, so im a fan of the flange