A Field Expedient Welder Only MacGyver Could Love

If you needed to weld something in a pinch, what’s the minimum complement of equipment you could get away with? In [Professor Bardal]’s case, it’s a couple of motorcycle batteries and a roll of flux-core wire, and not much else.

We suspect this one is going to elicit quite a few comments, not least by the welding fans who no doubt will be triggered by just about everything in the video below, especially by characterizing this as MIG welding; it’s FCAW, or flux-core arc welding. But it bears some superficial similarities to MIG, at least insofar as there’s a consumable wire electrode through which a high-current DC supply flows, creating enough heat to melt it and the base metal. In this case, the current is provided by a pair of 12-volt motorcycle batteries hooked together in series. There’s also a torch of sorts — a short length of copper capillary tubing with a 1-mm inside diameter clamped in the jaws of a stick welder stinger, or a pair of locking pliers if you’re really in a pinch. The torch is connected to the negative terminal on the battery with a jumper cable, and the positive terminal is connected to the workpiece.

To create the weld, a piece of 0.8-mm flux-core welding wire is threaded through the capillary and into the joint, and fed by hand as it’s consumed. It’s awkward and awful, but it works. Of course, there’s no control over amperage as there would be with a legit welding machine, which would make it hard to adapt this method to different materials. Weld quality appears poor, too. But we suspect that if you were in a position to need a welder like this, you wouldn’t really care about any of that.

Fabricobbled welding rigs seem to be [Professor Bardal]’s thing — witness this much more professional MIG welder, complete with a baking soda and vinegar shielding gas generator.

Thanks to [Danjovic] for the tip.