I bought a mig welder to weld on my subframe connectors and fix my exhaust. I just wondered if any body could give me some pointers on welding on connectors. Are the welding beads suppose to look like fish scales( back and forth motion) or a straight line with no movement exept forward? Also, are you suppose to drag the handle or do you or push it away? I've read a lot on the internet but everybody has there own way of doing it, I just want some simple answers that are the right way to do it. thanks

 

I "drag" the tip away from the weld as I go. Make sure both pieces are clean. You should practice with some scrap pieces of angle iron or something first to get the hang of it. Once you get the heat and feed settings where you need them, just take it slow and steady.

Like I said, practice first if you havent done it before.

Good Luck

 

That's a good start. Practice first and definitly use a dragging technique/motion.

The best advice I can give you is to make sure that everything is as clean as you can get it with a wire wheel, grinder, sandpaper, sandblast, etc. Use whatever you have, just make sure that the surfaces are as clean as possible.

 

Definitely practice a lot before you are welding on your car. When you do get to your car, you will want to use something to strip any paint and rust from the area you will be welding at. You need to have bare, shiny metal showing, and it would be a good idea to wipe the area with acetone as well. If you don't have any acetone, dont' sweat it (and don't substitute), but if you are going to be welding a lot in the future, it would be a good idea to pick some up. Also, make sure you get your ground as close as possible to the area you are welding in, and don't weld the same spot for to long. You could burn a hole in your subframes or even set your carpet on fire Welding subframes is probably not a good starter project. I would stay away from welding on your car until you are extremely comfortable with it. It would be a good idea to get a friend to do it for you and you watch him do it (through a mask of course ). Also, its a good idea to unplug your battery when welding on your car.

 

well, mig is actually as easy as pie, just point and shoot. That being said, I'd highly recommend that you take a class, or at least get a book. There is a lot that goes into good welds. You need experience so that you know how to adjust varialbes like wire feed speed and amperage (heat) so that you are getting proper penetration and a solid weld. And, clean clean clean. Even a tiny contaminant causes porosity and greatly reduces the weld strength.

I actually learned how to stick weld first and would highly recommend that to anyone else who is interested in learning to welding. It's by no means a requirement though. It's much harder to learn and takes a lot of practice, but what you learn will benefit you in the long run. To me its also important since there isn't always a mig available. Sometimes only some car batteries, jumpercables, and welding rod on the jeep trail, but for others that might not matter.

 

If you can, try to practice some welds in the same "position" that your subframes are in. Practicing on a work bench will be easy, but welding overhead might be challenging.

 

to add to what other people are saying, welding under a car can sometimes be more difficult for someone that isnt experienced. If you're not setup right gravity can hurt you Also, welding exhaust can sometimes be tricky, be careful to have the welding volts turned to an appropriate setting for the metal thickness of the pipe (typically a lower setting). And I agree that welding subframes may not be a good starter project for you.

 

I took welding in school, and we started out using stick welders. Then we went to the wire feed. Very easy just take sometime to get the hang of things. Your bead should be like a bunch of c's overlapping eachother, The most strength is gained by this method. To achieve welds like that, use a slow and steady back and forth motion while dragging the tip. Practice some on some scraps of steel, and once you feel comfortable have at her Not to hard at all!

 

Yes, try practicing circular motions. I've used a mig welder but I'm more of an arc welding type guy. Speed is not the key - consistency is.

 

"If theres slag you drag", which means if you are running flux core wire which creates slag just like welding with a stick you want to drag the gun, if you are running solid core wire which does not produce slag, you will push the gun from the side you are handed, if right handed put the gun to the right and point it towards you and push in. but it all depends on what kind of wire you are running, hopefully you got a good welder and not just a $200 piece of crap. You will find by using a cheaper welder and one of Lincolns higher end machines that most of the ease of welding is in the welder not the user.

If you are running solid core .035 copper wire and it is a true MIG welder and not a wire welder. Meaning you use a shielding gas (inert gas) and welding with solid core wire on steel will use either 100% CO2 or a trimix formula.

Another thing, if youve never welded before dont try to do your subframes, overhead is the hardest position to weld with any process. There is a lot of technique in making the weld work, sure anybody can make a MIG bead LOOK good, **** my dog could, but you have to think that these things are going to be under a ton of stress, better not have any coldlap or porosity in those beads, and if you dont know what those terms are just take your car to a shop and return the welder until you take a welding class.

Any other questions let me know.

Oh and arc welding applies to any kind of welding. That is a common term misusage, MIG, TIG, and stick are all ARC welding.

 

You're funny.

 

Sorry I got a little excited there was a post I know quite a bit about now.

 

Hmm.

Just make sure the piece is clean. No need to be sparkling especially for MIG welding steel. Aluminum? sure. not steel. Clean is important, not as important as some of you are making it (acetone? lol)

Ground as close to the work as possible and you shouldn't have problems with unhooking the battery and worrying about your pcm. I've never unhooked my battery when I weld on the car. Shortest path with the least resistance is the path the electricity is going to take.

How in the hell do you burn through your carpet welding up subframes? You have some major problems if you are starting the carpet on fire. The subframe connectors (at least mine, BMRs) are fully on the rails of the frame, maybe yours are different and attach to the floorpan somehow, but I doubt it. And blowing through 1/4" plate? Learn to weld hehe

As someone said, you want overlapping Cs, to get this make circles with the gun or just make Cs, either way works.

If theres slag you drag? nah. Not true, you can go either way, push or pull, either works well. Fusing using a TIG has no slag and you can drag it.

Just practice around on some different thicknesses of steel, until you get fairly decent at it. A class at a community college could help too. Its all practice though. Don't be worried about the idiots setting their cars on fire or blowing holes through their SFCs, unless you are a complete moron, that won't happen. I'd say after a some good practice in various positions you would be set to weld your SFCs on.

Good luck!

 

Thats just a technique i was tought that works in most cases of MIG welding.

You will want your wire feed speed around 150 or a little more and set the volts to about 19, but adjust the volts accordingly while welding until it runs smooth

 

Mig welding is very simple very little technique involved for most stuff. I would say the MOST important thing on a MIG is getting the temp and speed right. If you have to much or to little wire speed it will look like crap. If you get the welder set right just about anyone can mig weld.