Introduction: METAL MELTER!

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Here's a microwave oven transformer that's been modified into a dangerous little device. Now it can pump out 800 amps of electrical current, so let's use it to melt some metal!



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    Hello Wildfire Phoenix here. This looks really cool and is something that I will do with microwave transformers (definitely an array of them).

    I was wondering could someone, swap the plug for a light switch attached to a powerful car battery for this amazing metal melter?

    No transformers do not work on DC current.

    You can however use car batteries and weld with them. I won't explain the process because you can blow up the battery and get blinded by the acid.

    I built an arc welder from 6 microwave oven transformers.

    Would more turns on the secondary give more current?What about more turns in the primary?Can the core be solid steel instead of laminated?Lotsa questions,but I'm looking for more amps,and since I have a mill,thinking of scaling up the MOT to 2x size with a custom core if possible or feasible.

    keep the primary the same, if you want a higher current ( at lower voltage ) output then reduce the secondary winds. NOOOOO! if you use a solid steel core than you'd be wasting half the energy by inducing eddy current which generate heat in the core.

    The way I understand transformers, it's all about the ratio of the windings (primary to secondary). So if you maintain the amount of windings on the primary and increase the windings on the secondary, then yes, the current increases. In terms of the core, solid steel becomes permanently magnetized if exposed to a powerful enough magnetic field.

    When I made this it was really loud and got really hot quickly. I cut the transformer apart with a grinder. Maybe that was a mistake, is the reason for all those thin ply of insulated metal to reduce eddie current induced excess heating of the transformer? I barely know what Im saying there but Im thinking thats correct because it got real hot real quick.

    this thing is awesome! i used 14 awg 3 conductor copper wire, and paralleled all 3 conductors. the max short circuit current is 460 amps at 3.69 volts. it easily melts nails.

    love your youtube channel, I thought that metal foundry would be great for prototyping parts for projects, good job Grant :3

    It is a good demonstration piece for showing low voltage with high current


    Would this work as a smelter for iron? I have a bunch of rebar lying around, and I'm thinking of trying to melt it down into blocks, then forge them into swords.