Nifty MIG Welder Built From Scrap

A MIG welder is a great tool to have. With machine fed wire and gas protecting the arc, it can make it easy to weld well without requiring a lot of manual skill from the operator. [PROFESSOR PARDAL BRASIL] decided to build his own MIG welder using scrap parts, and it’s an inspiring bit of work.

The build is along the lines of so many YouTube contraptions, using bits and pieces thrown together in oddball ways. A windscreen wiper motor is used to create a wire feeder, with jammed-up ball bearings acting as rollers. Speed control of the wiper motor appears to be via a variable resistor created by moving two plates closer together in a bath of salt water. This enables the wire feed rate to be easily controlled, albeit in a wet and messy fashion. The build includes a device for producing carbon dioxide for use as shielding gas, too. This is achieved by mixing a solution of water and bicarbonate soda with vinegar, and then pumping the resulting carbon dioxide into an inner tube for storage. The power supply for actually creating an arc comes courtesy of car batteries.

The resulting welder is janky as all heck, but it does successfully weld some steel plates together. Job done, as they say. Video after the break. 

Thanks to [Danjovic] for the tip!

29 thoughts on “Nifty MIG Welder Built From Scrap

    1. A lot of people make youtube videos of their projects but don’t get a cent for it. Monetizing videos isn’t as easy as you think. The question isn’t about the people making the videos, but the other people promoting the videos that are solely made to make money. But then again, if the video is about something interesting or inspiring, than what’s the problem.

      1. This Youtuber in question has 800,000 subscribers and over 212 million views across 197 videos. So yes, he’s definitely making a living off his videos.

        However, if it bothers you, install an adblocker, and be smug in the knowledge their hard work isn’t getting a dime from you. ;)

        1. Not for long – youtube is already enforcing their new policies about ad-blocking. I’m not sure if there’s a workaround like a Pi-Hole or something like that, never looked into it.

          Also, did something change in HaD’s comment system? It looks… different. Hope it runs different too (hopefully better)

          1. They’ve been enforcing their no ripping policy for years now.

            They WILL win.
            Right after the ‘war on drugs’ is won, Elon is on Mars mooning the Hubble’s replacement and we’re all using Larry Ellison’s thin clients to browse PornHub.

  1. I just go over to Harbor Freight pick up a little one for 120$! Not great, but not bad either. I wouldn’t trust that weld on the connecting rod though, not the kind of thing you should ever weld.

    1. As a Harbor Freight welder user, I can tell that $120 will not get you one of their MIG welders; it will get their cheapest flux core welder, which will give a passable weld, but nowhere MIG quality. And flux core wire is obscenely expensive. It will take over twice that $120 to break into MIG welding. And besides, just going and buying what you can make is not in the true maker/hacker spirit; however, making the tools that make the tools, now that’s that’s the true Way of the Hacker!

      1. I bought a Craftsman MIG for $47 while Sesrs was gasping their final breaths. And 97 cents for a spool of MIG wire was nice too!
        Though I did have to shell out $80 for a filled CO2/argon tank.

        1. That’s a screaming bargain for the tank.

          We could ‘arbitrage’ those to a state that charges deposit. Not sure if the inspections travel though. Still, an 18-wheeler full of empty tanks would be a few bucks.

    1. That’s the downside of a spool gun, as opposed to a hose gun, but it’s cheap and it works, and it’s more suited to aluminum wire, but for aluminum you would, IIRC, have to change gassed. And a spool gun is better than no gun.

    1. G. K. Chesterton, the famous British writer, was once invited to a meeting of the leading intellectuals in England. They were asked if they were shipwrecked on an island, what would be the one book they would want to have with them. Everyone expected Chesterton, a prominent Christian, to say “the Bible.” When it came his turn to speak, however, Chesterton said that if he were shipwrecked on a desert island, he’d like to have “Thomas’s Guide to Practical Shipbuilding.”

  2. I’ve already got a basic MIG welder, but something like this would be good as a spool-gun for welding aluminium. With it being a basic (90A) welder it can only handle thin filler wire, getting that to push reliably through cheap wire-liner would be frustrating.

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