Improbably Cheap Pocket Welder Gets An ESP32 Makeover

If you move in certain shady circles, you may have noticed the crop of improbably cheap “pocket welders” popping up on the market these days. They’re all variations on a theme, most with wildly optimistic specs minimal accessories of the lowest possible quality. But their tiny size and matching price make them irresistible to the would-be welder, as well as attractive to hardware hackers.

With a 220-V outlet in the garage waiting to be filled and well-knowing the risks, [Mr. RC-Cam] purchased one of these diminutive welding machines. Its shortcomings were immediately apparent, and a complete rework of the welder was undertaken. After addressing safety issues like the lack of a ground connection, [Mr. RC-Cam] added a color-matched 3D-printed hood to house a fancy new LCD touchscreen display. Backing that up is an ESP32 with Bluetooth, which supports remote control via a key fob. He also added a current sense board that uses the welder’s current shunt to measure welding current. Expediently calibrated using a waffle iron and a milli-ohmmeter, the sensor showed that the 200A max advertised for the welder was more like 100A. He tried adding some big electrolytics to fix the current issues, but no dice. With a decent stinger and ground clamp, the modified welder is good enough for his needs, and much was learned in the process. We call that a hacking win.

As an aside, [This Old Tony] recently did a review on a similar welder if you want more details on the internals. We also covered the conversion of a buzz-box to a TIG welder recently, should that be more your style.

25 thoughts on “Improbably Cheap Pocket Welder Gets An ESP32 Makeover

  1. This is a cool electronic project, but no way am I letting this thing near anything I want to weld properly.

    Keeping it aside or in a small kit for a rainy day on the other hand….

    1. Sure there are, if you pay for them. Think of this welder as the Uber or the AirBNB of welding equipment: much cheaper than the competition, because they’ve decided to skip all the expensive steps like verification and certification.

  2. How much? $60.00?

    What ever happened to common sense? There have been some–well, at least one–VERY well done article(s) here on Hackaday in the very recent past on the current spate of $100 to $120 welders, and how GOOD they are (I think it was by Jenny List).

    “hacking” is no excuse for a lack of common sense; the very spirit of ‘hacking’ is to end up with something more usable; to be able to make a “…silk purse out of a cow’s ear…”; and NOT to put whipped cream on a turd–which is the most charitable thing which can be claimed for this ‘hack’.

    This truly deserves the admonition of “NOT A HACK”.

    A very good quote by Fred Brooks, the author of The Mythical Man-Month, and the man who salvaged IBM’s ‘in-tatters’ IBM 360 Computer program when it was on the brink of destroying the Company, is

    “Originality is no excuse for stupidity.”

    1. It was, indeed, Jenny List in her very good article–

      “Is A Cheap Inverter Welder Worth It?”
      September 23, 2019 by Jenny List; 133 comments.

      Some quotes from the introduction…

      “…What I’d bought from my local Aldi was a Workzone WWIW-80, an 80 A unit that had cost me somewhere just over £60 (about $75), and came with welding leads…”

      “…These small inverter welders are fairly generic, so they can be found with a variety of brands and specifications at a lower price online if you don’t mind forgoing the generous Aldi 3 year guarantee. The cheapest I’ve seen was about £35, or $44, but that price included only the inverter, without welding leads…”

      The article, and comments, provide a very good tutorial on these amazing devices.

      Lastly, I would like to apologize profusely for my unthinkable, unspeakable gaffe regarding “…a cow’s ear…”, and for not giving sows their rightful due.

    2. “the very spirit of ‘hacking’ is to end up with something more usable” – Which he certainly did. It may not be as usable as a Lincoln or a Miller, or even one of the welders Jenny looked at, but it was good enough for his needs and demonstrably better – and safer – than what he started with. Sorry to say, but that’s a hack.

  3. “…color-matched 3D-printed hood to house a fancy new LCB touchscreen display.”

    Maybe I’m out of the loop but I don’t believe there is such a thing as an LCB display…

  4. I for one think this is great.
    But I’d grow it into an old welder I have had for around 30 years. It is a very basic electronic “light dimmer” sort of controlled one. This welder has had a lot of work, but an upgrade would be fun. I’ve also picked up a couple of welders tossed out, and they need fixing, along with Megga testing etc. to ensure they are safe for a start.
    And upgrading this “pig’s ear” ( I believe cows need not apply ) is wonderful. Thank you for this idea Mr RCAM :)

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