Ok im trying to figure out what to do here, heres my problem I have some patch panels to weld, I used to borrow my dads miller mig when i did this but since he moved to the other side of the country thats not an option any more. I have a little 110v century mig welder i picked up but the wire is constantly live, not sure if it is made to be this way or if the contactor is bad? i have not pulled it apart. I have oxy/act. bottles that i could go fill and gas weld with, but i havent done this on sheetmetal in a long time. or should i spring for a tig machine ( the wife might kill me ) What should i do im kinda going crazy trying to decide
A properly working 110v mig is a good machine of patching/sheet metal. Less distortion than bigger set-ups. TIG nice but not necessary.
Buy your own Miller MIG, I have a 115 volt Miller 140, with .023 wire and C25 gas you will be able to weld body metal and all your ch***is - frame brackets too. I'm amazed at the machines capabilities for a relatively small affordable machine.
There's nothing wrong with your machine, the cheaper ones have live torches, my old Sears unit which I had for 15 years was like that. I actually preferred it, but now I'm used to the dead torch on my Lincoln.
I had an old Century "live wire" as my first home unit. Worked great and i pounded the **** out of it doing all kinds of repairs for people on the side, plus my own work. The live wire can give you a good eye flash and you will spark it off at times, so I'd suggest you get a self-darkening helmet and flip the lid before you actually start to get into the weld. You can see pretty good when they're not activated. Even a cheap one can save your eyes from the pain of a welders flash.
use the M.I.G. I learned to gas weld in 1973,, did it alot when I first started doing muffler work in the 70's bought a MIG and haven't gas welded since.
I need to make a video. there is not a whole lot of info out there on hammer welding. once you get it you'll hate picking up a mig welder to do sheet metal.
not meaning to go off topic but... I saw on TV years ago as the prototype Cadillac Alante was being handbuilt in so. cal. The shop hired a father and 2 sons from Europe for sheetmetal work on this car. They were making that big flat hood from two halves..the father ran the torch and rod, one son on top with hammer, the other son under the hood with the dolly....ON a BIG FLAT hood!! ..right down the middle. Wow
i think im going to try and find some ez grind wire and get the gas hooked up to my little century welder, it is set up for it but has flux wire in it right now which i hate. I should be fine just had some trouble yesterday trying to welding in a small patch panel on a hood and it pissed me off
I have an old Century" live wire" I find that when I stop welding that if I touch the torch to a pcs. of metal it sparks and then it dead till you pull the triger again. Try that and see if it work that way for you.
Hey, At one time, this was the only way larger body panels were built. The average english wheel was only 3' deep, so to build a roof panel ment several pieces would need to be shaped, then welded together. The limited production Ferrari up into the 50s was built from many panels, all gas welded together, then metalfinished. Few coachbuilt vehicles had pressed formed panels up into the 60s! On the welding question: I'd fill up your bottles, buy new hoses, and cut some coupons from sheet, and weld, first fusion, then lap (both with/out filler rod) next work several p***es with just filler rod. Next try a few "T" welds, and all of the above welds in as many positions as you can think of. Gas welding is not hard to learn/relearn, it just takes pratice. A squirtgun (mig) welder isn't all that usefull for real/serious sheetmetal work, and usually the only welding a ''puttyflinger" can master! When you factor all the grinding, fiddel ****in around with the cheaper machines to keep them in the fight, they just don't pencil out. Hammerwelding is easy to master once you get gas welding under your belt. You do have to plan your seams where you join a panel so you can get behind them with a dolly/s****, but filler free welds and panels are possible once you figger it all out. " A little putty and paint makes a metalman what he ain't "
If you hammer weld with a mig and EZ Grind wire you'll be fine. Are you in the biz? A job you may not do again for another 5-10yrs? Mig it but don't use flux core. Might as well use bondo. To hammer weld with a mig you need a helper ready to peen the weld for you when you let go of the trigger. You weld and inch or less at a time and move around to keep heat in check. Once welded if you use the EZ you can grind and finnish with a 50 grit 1st then go to an 80. Overlap your welds right and get a rythm with a helper and you can take the Pepsi Challenge with a tig or gas weld. I prefer the tig but there's times and places where it's not practical. Using regular er70s6 it's better to get some weld on both sides, both hammered so when you grind and finish the face you don't want cracks. Go for perfect fits and **** welds, no overlaps and the gap should be close to the wire size. Use round corners so the mig won't burn the sharp edges, and actually this helps big with tig and gas too. Practice makes perfect so set up on some s**** and figure out your hammer work. That rounded mig weld needs to hit while it's cooling from red and few seconds after. Hammer it hard enough to gently flatten the surface of the weld and not much more. Ok enuff for now.
That's the way it's wired to operate. When starting a weld, don't touch the wire to the work, just hold it close to the work and pull the trigger. That will advance the wire onto the work. You are on your way....................
The prolem im having is no access to the back side, ez mig wire is going to be my option for now. i love gas welding but like i said i havent done it in a long time and im on a schedule to get these panels in and get this car painted in a couple weeks.
I gas weld ALL my patch panels! just practice on some s**** you will thank yourself when you get it right
I read and read about this but I was wondering something...Can you a rag dipped in cold water behind what your welding to keep the warpage down..?
Thats just going to kill penetration and probably warp it more. The faster it cools the more the weld shrinks. The more shrinkage at the weld the more warp in the panel. The hip bone's connected to the leg bone.
I prefer gas welding, but it sounds like you already have a functional little mig. They work fine, no sence in reinventing the wheel for a patch pannel.
Its going to shrink, thats what happens when you apply heat to metal. The trick is how to stretch it back to shape. One of the first things you should do before cutting anything is to look for a place where you can have access to the back side then try and cut there. Even if it means making your patches bigger. Sometimes your just screwed and have to deal with it. Mig is fine for sheetmetal, you want to use enough heat to get good penetration on the first hit, tack here, then there, then over there. A copper backer on the inside is a big help too, and can save some grinding on the inside. If you have access to the backside, lay down a few tacks, grind them not quite flush, hammer/dolly each one and then repeat. I cut my patches with a slight gap, usually the thickness of the material your welding, try to keep it even. When you are welding the panel watch the gap, when it starts to close up thats a good indicator that its time to stop welding and start hammering. When the panel starts getting hot all over, stop let it cool and start again after its cooled. Not sure if this will help you but I figured I'd offer it anyway. Good luck!
My 120V MIG is a Craftsman, made by Century- it's live wire, also. I'd say you have a concensus that there's not a problem with yours. I wouldn't buy a TIG just for this job unless you're getting paid REALLY well. I'm not a big fan of 120V MIGs, but the one you have will do just fine for patch panels. I agree with your asessment to ditch the flux core wire. There are people who love the stuff, and they obviously have success with it to love it, but I hate it.
You really do need to access the back side of the weld. To restate what others have said, the metal shrinks when it cools - nothing you can do to change that, just the nature of the metal - so you'll need to hammer/dolly your weld. Can't get around it short of a m***ive amount of bondo. Since you love gas welding, thats probably what you should do because that is a known tecnique to you and you'll know when things are going sour. There is more to it than just throwing filler metal into a seam. The last thing you said is the scarry thing, something about being on a schedule and having to get done by such-n-such...throw that notion right out the window, this is your hot rod. There are no schedules to keep, the most important thing is to do the work proper. There is a very good possibility that you will screw it up and have to cut the whole mess out and do it over, we've all had to do it - its part of the enjoyment of working on a hot rod. Post some pics of your patch welding. Good luck, oj
Do you guys use compressed air to cool welds instead of water? Is air better that water? I figured it would cool the metal slower and more evenly than water. Any advice?
once the metal is cool enough that its not glowing you can cool it anyway you want and it won't harden, at least not enough to notice. It really only causes an issue when your quenching red hot metal. You should always wait until the metal stops glowing before you quench with air, oil, or water, other wise you'll harden the metal.