Turn an ATX Power Supply in to a Welder?

I was wondering if I can turn an ATX power supply in to a welder:
Before I write down the specs/amps of the power supply, I want to say that I have no experience in welding, I'm wondering if it's posssible to make a small welder out of an ATX power supply.

Is there some kind of minimum current that you have to pass to start welding (softer?) metals?
The lower the voltage the better right?

I didn't give a lot of information, Because I don't know what to ask...

Thanks :)

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first you need to learn to weld with a real welder. Take a class, get the safety equipment and then have it looked at by a pro

Yonatan24 (author)  bravoechonovember11 year ago

So I'll have to try to bond metals with a 40W soldering iron...


No problem! Though a soldering iron might hold the metals together it wouldn't last-welding actually melts the two pieces of metal together (as in if you crank the amps up you can cut through solid steel)

Your best bet for holding two pieces together without a welder is probably be epoxy

Yonatan24 (author) 9 months ago

861 views! WOW!

cdanila111 year ago

The simplest welder is a jar of brine with two copper wires distantly sunk in it. One wire goes to the live and the other to the stick holder. Neutral is common. This is risky because there will be 110 or 220 volts in the brine and on the stick but you will be fine if you don't touch any of those with your bare skin.


-You can get electrocuted if you are not careful.

-This system will not weld anything connected to the earth if your house has a Ground Fault Interrupter (like modern homes do), because the GFI will perceive the current through earth as a shock to a person and will instantly shut down the power.

-It draws a lot of current (about 25 amps at 220 volts), as you will see the brine getting hot in under a minute of welding.


-It's the cheapest and simplest way :)

Yonatan24 (author)  cdanila111 year ago


25A @220V? I don't think the outlets we have can supply that much...

I'll have to keep that in mind :)

That would be the peak current for 2.5mm sticks and thick steel - the current is directly proportional with the depth of the wires in the brine (assuming the same distance between them and the same salts concentration) .

Remember to shield your exposed skin from the light radiation by wearing clothing (if you've welded before you know it burns like the sun on a hot day) and ideally use a fan to suck away the smoke because it's toxic - especially galvanized metals smoke.

No, you need a certain minimum, typically 35-40 V to get a stable arc, and you need some means to limit the current in the arc when its struck,.

Yonatan24 (author)  steveastrouk1 year ago

I've seen The King of Random make a welder out of two old microwave transformers, Which were ~3V (I believe they were connected in parallel)

If I don't have any current limiting system, I'll probably blow a fuse in the power supply, So how do I make one?

A weld needs 35-50 VDC like Steve says, at 25 to 300 amperes depending on the metal thickness... the weld arc will damage your skin and EYES..

A current limit resistor is a discarded water heater electrode...

I once welded wearing a Tshirt (bad mistake) my chest pealed six times.

You can also spot weld a lot safer.