You can weld aluminium with a mig but it's not the ideal way of doing it, i think the guys who weld up alloy bodies for trucks use tig sets to get a cleaner weld, for odd jobs you can make a standard mig do the job, the correct kit would be a special torch with the wire reel on the handle, to avoid problems with the soft wire kinking in the liner, but the suggestion to use a larger bore tip will work for odd jobs.
Quite a while ago now i used my mig to repair the rear wing on a 90 that had accident damage to about half way up the fuel filler. Rather than replace the whole wing i made uo a repair panel by cutting the bit i needed off a a scrap landrover, drilling out the spot welds and then made a stepped joint in the panel with a joddler tool.
I used a small disposable argon cylinder, and a tiny roll of aluminium wire, welded along the stepped joint and ground it back and skimmed it with filler, and plug welded the holes where the original spot welds were. As someone said earlier, it's more like brazing than welding, the melting point of aluminium is much lower than steel so you can soon blow a hole in it, you get a pool of molten metal which you have to try and control to fill the gap up and form the weld.
The OP would perhaps be better pop riveting some repair patches over holes in the body work if it's just a rough vehicle, or fitting new panels if they want a tidy repair, you'd be on a hiding to nothing trying to weld aluminium with a gasless mig, then again i'd say you were on a hiding to nothing trying to weld anything with a gasless mig though.
Quite a while ago now i used my mig to repair the rear wing on a 90 that had accident damage to about half way up the fuel filler. Rather than replace the whole wing i made uo a repair panel by cutting the bit i needed off a a scrap landrover, drilling out the spot welds and then made a stepped joint in the panel with a joddler tool.
I used a small disposable argon cylinder, and a tiny roll of aluminium wire, welded along the stepped joint and ground it back and skimmed it with filler, and plug welded the holes where the original spot welds were. As someone said earlier, it's more like brazing than welding, the melting point of aluminium is much lower than steel so you can soon blow a hole in it, you get a pool of molten metal which you have to try and control to fill the gap up and form the weld.
The OP would perhaps be better pop riveting some repair patches over holes in the body work if it's just a rough vehicle, or fitting new panels if they want a tidy repair, you'd be on a hiding to nothing trying to weld aluminium with a gasless mig, then again i'd say you were on a hiding to nothing trying to weld anything with a gasless mig though.
khaos
New Member
You've seen what happens to defender doors right? Apart from the fact it will be a miracle to even get a weld because for a start the ally will melt well before the steel amongst other reasons, it will react very quickly and become corroded.
Ryder
Having a senior moment
HI Khaos... yeah MHM mentioned that this was not practical but the question had to be asked!
Basilseal... to be honest the gasless mig has not been bad for welding steel. It has proved to be a simple device to operate and bearing in mind that it is owned and mostly operated by an 11 year old I think he is getting on quite well with it... improving all the time of course. Once he can get a decent result with this welder then spending a few hundred quid on a decent gas one with more bells and whistles should mean that he gets an even better result than he would have done otherwise...(if that makes sense).
Basilseal... to be honest the gasless mig has not been bad for welding steel. It has proved to be a simple device to operate and bearing in mind that it is owned and mostly operated by an 11 year old I think he is getting on quite well with it... improving all the time of course. Once he can get a decent result with this welder then spending a few hundred quid on a decent gas one with more bells and whistles should mean that he gets an even better result than he would have done otherwise...(if that makes sense).
He's doing well at 11, fair play to him, when i was welding up series land rovers for 'fun' i was using a stick welder
