MIG Welder for very thin sheet metal

[LucasJ]

Hi,

I have some experience with conventional MIG welders welding 2-10 mm sheet metal. They perform very well, but welding a 1 mm sheet is almost impossible: Either I have burn-through or the bead just lays on top with very bad penetration.

I am looking for a portable 1-phase MIG welder which enables me to weld continous beads in sheet metal down to 1 mm or less without distortion. Are my requirements unrealistic?

Price is of no importance.

Thanks,

Lucas

 

[Gareth J]

without distortion. Are my requirements unrealistic?

Yup, afraid so. Zero distortion is a non thing.

 

[mike 109444]

A piece of copper pipe, flattened and held to the back of where you weld should help to stop the blow through.

 

[Jim Davey]

Very difficult unless you have a highly specialised pulse MIG like an EWM Cold-Arc or Lincoln STT machine that is tailor made to keep the short circuit current incredibly low and therefore limit the heat input when welding extremely thin section materials.
I imagine both of those machines will be more expensive than you were hoping for though.

 

[LucasJ]

Merkle offers a machine called Mobimig 180 which has an option called ColdMig. To me it looks similar to EWM Cold Arc. The Merkle Machine costs less than 2000 Euros. Anyone experience with that machine?

 

[Kent]

It don't take a better machine it takes know how and continuous don't form part of your solution
Lots of little tacks. Downhill and back stepping with an eye on the weld connected to the go switch will be required

 

[pedrobedro]

I can put a continuous run on 20g with my Kemppi Minarcmig without blowing holes but your distortion free requirement is asking a lot. If you put heat into metal it is going to expand.

 

[Jim Davey]

Cold-Arc and other similar processes allow you to put continuous (if needed) runs on thin sheet without the need to travel ridiculously fast to avoid burn through. This is significantly faster and much neater than overlapping spots, however that works perfectly well if expensive kit is impractical for the amount of work you have or the return that work provides. If you were a factory producing thin sheetmetal pressings with lots of open corner joints say, then it would be a perfect joining solution.

 

[langy]

If you back it with a piece of copper tube flattened it will stop you blowing holes, to cut down on distortion use a wet rag, it will still move a bit but you can get it back by heating and a wet rag or by using a soft disc as a shrinking disc (backwards) and a wet rag