Welding Tips and Tricks

I made and ARC welder using some Microwave oven transformers. Check it here. https://goo.gl/AfKDre
I get around 32 volts and 175 amps(max). When I did welding the arc is starting slow it means it takes time if you see in the video. The penetration is not so good. I gave it few tests and fund that only the rod was melting but not penetrating the base metal. I was thinking to increase the power with another transformer. So now should I increase the voltage or current here?

You need a lot more amps. I suspect that your amp measurement is incorrect. There is no way you are getting 175 amps to the stinger or that would weld much better. Your wires delivering the current to the stinger/ground clamp are too small to possibly be delivering the full 175 amps. How did you arrive at that number?

I'm guessing 175A "peak to peak", for an effective peak amperage of 87.5, and and RMS (effective) amperage of 61. That, at 32V (very low OCV for stick welding) results in an overall power input to the metal and the rod of 1980 Watts.

You should be putting 6-7KW into a weld, at a minimum.

Steve S

Louie1961 wrote:You need a lot more amps. I suspect that your amp measurement is incorrect. There is no way you are getting 175 amps to the stinger or that would weld much better. Your wires delivering the current to the stinger/ground clamp are too small to possibly be delivering the full 175 amps. How did you arrive at that number?

Might be wrong. I used the old Ammeter and it had 350 Amp capacity and when I used it the needle pointed at center of the dial. So any way it is above 125 Amps. Do I need high voltage or current here?

Otto Nobedder wrote:I'm guessing 175A "peak to peak", for an effective peak amperage of 87.5, and and RMS (effective) amperage of 61. That, at 32V (very low OCV for stick welding) results in an overall power input to the metal and the rod of 1980 Watts.

You should be putting 6-7KW into a weld, at a minimum.

Steve S

So according to you. I need high voltage, high current or both. What is the minimum you recommend for homemade one. That can work just fine. Not much heavy duty.

you need more power in general. for sure more amps. more volts wouldn't hurt either.

To achieve 140A current (suitable for 1/8" 6013 rod) with a 32V output will require an input current (at 110 VAC) of 40.7 amps, assuming no losses. That's a big breaker, and some fat wire.

If you can double the output voltage to 64 (more appropriate for stick welding), you drop that input current to 20.4 amps, and can run from a 30A breaker.

Steve S

Louie1961 wrote:you need more power in general. for sure more amps. more volts wouldn't hurt either.

Thanks. I will try to increase both.

Otto Nobedder wrote:To achieve 140A current (suitable for 1/8" 6013 rod) with a 32V output will require an input current (at 110 VAC) of 40.7 amps, assuming no losses. That's a big breaker, and some fat wire.

If you can double the output voltage to 64 (more appropriate for stick welding), you drop that input current to 20.4 amps, and can run from a 30A breaker.

Steve S

I have 220V supply and 30 Amp main breaker at home. So I think you get the maths. Ok I will try to increase both voltage and Current but tel me which factor is important for penetration and better joining?

that question has been answered, twice.

Wattage melts metal. The multiplication of volts times amps. Too much amperage, not enough voltage the arc won't work. Too much voltage, it's just a short circuit.

Thanks