DC Arc Welder Made From a Microwave Oven

At the request of countless viewers, I made this highly detailed video which includes a schematic so you can make your own Microwave Oven DC Stick Welder. It is best to get the welder working good with AC before converting to DC output as shown here.
Link to schematic here:
i.postimg.cc/q...
Thanks For Watching!
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[@ryanthoms1802]

How did you determine the capacitor size?

[@richardworden9747]

When you say use #10 wire . Can I use #10 THHN and about how many feet do I need ? Please. I see the video is from 8 years ago . If anyone can help me .. please do and thanks Much.

[@lajoyalobos2009]

Very good, clear explanation. Thank you!

[@electronicsNmore]

Glad you enjoyed the video! Be sure to look over my extensive video playlists for other great/helpful videos of interest to you, subscribe, and most importantly share my channel with many others. Without viewer support(sharing of my channel), helpful videos like this may not be uploaded in the future. Thank you!

[@jimburnsjr.]

Exceptional video, great tone of voice and professionalism; thank you very much for your investment in the community. Hope you are doing very well

[@electronicsNmore]

+Jim Burns, Jr. Glad you enjoyed the video! Be sure to share and rate thumbs up. Thank you

[@martinlb1]

Thanks for this great video and information! Would you be too bored to answer the questions from a newbie? 1-How do you determine that you need about 40V from the secondary to weld? (In other words, why not to use a #1 gage wire which sustains a higher amp and provides about 1-2 V? or Why not to use only one transformer with an output of 20V?) 2-Is this wrong to think that the total power from all secondary is equal to the power from the source (120Vx15A=1800W) so adding more transformers only changes the voltage and amperage but not the power?

[@oscarvalenzuela262]

It is not necesary to use to use a chocke in output?, excellent idea thanks!!

[@electronicsNmore]

I never had any problems the way it was constructed. Thanks for watching Oscar!

[@TheF22raptorang]

the best Goooooooooood Job sir Thank so much

[@secretagent5658]

Ok this is good in theory and on paper. But you did not actually do it so we don't know if this actually works. So bad video. Waste of my time

[@electronicsNmore]

What a fool. 😂 I have another video showing a completed unit in operation, this was a follow-up video to show the schematic. Use your brains before posting stupid comments. People like you waste my time.

[@secretagent5658]

@@electronicsNmore What's it called so I can watch it?

[@angelobryan4699]

What about power control?

[@jakenbaked87]

Ah yes I am using an SRC to limit the current but then I drop my voltage too low to use... Think I might build a rectifier to form a DC current and also gut another MOT and use it as a strong inductor to limit the current flow. Did you wind your transformers with 12ga wire for the secondary?

[@ALEFILES]

Dear electronicsNmore, this is a AMAZING project, both, the battery charger and this are very good projects! In my country we have 220VAC, 50Hz...Which changes I must make in this circuit? because you designed it to 120VAC 60 HZ...The BIG capacitors are expensives? The 6 diodes are from a car alternator? If I do not find this 6 diodes, can I make with 6 individual power diodes? (i.e. 20A each). Tthanks a lot for your time!!!

[@electronicsNmore]

You have to use the rectifier/diodes from a car alternator. That is the best source. You can use the 220V/50hz transformer from your microwave oven. Nothing else changes from this video. The only difference is your transformer has twice as many turns on the primary winding, or more turns of a thinner gauge wire, so it can be used on 220V. Thanks for watching! Be sure to check out all my other videos.

[@electronicsNmore]

sure. :-)

[@oscarvalenzuela262]

Sincerely good job, thanks for sharing, if i use just two transformers without the bridge rectifing system, what happen? or it is better use this! sorry for my English, i hope you understand what im trying to say!! in other words, if i convert ac to dc it is convinient?? thanks a lot

[@electronicsNmore]

You can use a AC output.

[@jakenbaked87]

I made one of these welders, and my problem is that I'm getting too much current and not enough voltage-- my two transformers wired together with 10ga wire produces around 33 volts. I burn through 16ga metal... I can't add anymore loops in the transformer bc there just isn't enough room. do you have any suggestions? Input 120vac.

[@electronicsNmore]

You made the AC version? Correct? Are you using a thin electrode? 1/16"? Usually you don't use an arc welder for thin sheet metal(but 16ga should be fine). You have to move fast or you will burn a hole right through. I can do it with my DC unit, but sometimes I also burn a hole through. You need to regulate the current going into the 120V step down transformer(MOT) to reduce the current output. Your 33V should be fine. Your problem is too much current, not the voltage. You need a triac type circuit to regulate the 120V line AC. You can also try a heavy duty, high wattage fan speed controller to regulate the current so you can weld thin sheets. Thanks For Watching! Be sure to check out my video playlists as well.

[@ИлияГаберов]

Hello mindtomachine i want ask you somenthing, i maded welder from microwave transformers and in AC they got power of 120A, but after rectification with 4 diodes 200A and homemade choke with 20 turns of same wire as the second coils of transformers in case 8 gadge on a same microwave transformer as others i got power from only 55-60A why? any idea ? i disconected choke tryed only with rectification and amperage was still drop to 60, aftert that i disconected rectification bridge and left only choke/inductor but amperage was still on 55-60 even on AC, and when i disconect both choke and rectification bridge just the three transformers welding power is 120A what i do wrong or there is just to many losses because of bad calculacion and that is normal, did you got same problem on your welder?

[@electronicsNmore]

The end result is LOWER voltage and high current. 55-60A is very good!

[@yottky]

what I understand is that the electric arc length is varying (hence the current and hence the welding temperature) since the human hands holding the electrode cannot be steady. And we need some CONSTANT CURRENT circuit to compensate for this. But in all the MOT based arc welders found on yt, there seems to be no such a facility. How can it really work?

[@electronicsNmore]

Using a small diameter rod keeps the current down.

[@tonysshadow]

Might want to rename or retag this video. This is the makings for a dang fine high voltage golf cart charger or DIY batteries with high charge and discharge rates.

[@electronicsNmore]

LOL. True, never thought about that. Thanks for watching!

[@TheF22raptorang]

and how i control curent and volt out put for Other size of stick welder

[@electronicsNmore]

In the near future I will be adding a simple current control for welders to my video list.

[@evilcowboy]

One way of doing it is with multi-winding transformers. This allows for you to step up or step down the voltage based on which winding the transformer is using, and allows for the ability for several varying winding amounts to be use in a single transformer. I am pretty sure the MOT Arc welder can be done with a single transformer this way but would require you to somehow make the transformer large enough to wind it with multiple winding's. It would consolidate the design providing a more compact design, while giving the versatility of selecting different voltages thus producing more or less current based on which winding is being used. The negative effect of doing this idea is you may require more than 1 fan but personally I think an intake fan in front while providing an exhaust fan on the rear would make it a better design anyway. His schematic is very well done and honestly if you can't grasp what he has done here and how to incorporate the variable voltage selection then you may want to hold off on building it until you fully understand it. Even simply overlooking the polarity of the 18500uf Cap will result in a very bad day for you as it would cause it to explode and a 18500UF Cap exploding in your face is not most people's idea of a good day. The possibility of reversed polarity on that cap is possible if you incorporate a voltage selector in a design that did not have it without knowing what all the parts are doing. Its roughly like starting an engine knowing you cross threaded a spark plug and the threads are gone, which is a very bad idea if you like your head to not have holes in it. Just a safety warning not being a dick. His schematic is very well explained in the video.

[@TheF22raptorang]

$20 Homebuilt DC Welder - Power Control Circuit they is very complex schematic but your schematic is no complex I like so much sir AND can i use choke than capacitor ? ; what differance choke V.s. capacitor

[@electronicsNmore]

Yes, I saw that video before. It does seem to work, but I prefer to use a triac.

[@MYNICEEV]

Great tutorial. Many thanks. Would it be ok to use the microwave AC fan instead of a DC one?

[@muneebibrahim7759]

what is the circuit of high frequency pvc welding machine single head

[@droquesteni]

Hello sir! Great tutorial! Do you still have the shematics? Link is broke. Can i add in the final capacitor some capacitors in paralell to achieve the capacitance? Again awesome job! Respect!

[@electronicsNmore]

Try now. Yes, capacitors in parallel is OK.

[@droquesteni]

@@electronicsNmore great! Thanks!!

[@TheF22raptorang]

Can I use volume to control input Current of primary coil ? in my home use 220 V 50 Hz.

[@electronicsNmore]

No. You will fry the potentiometer instantly. In a week or two I will be adding a video to show how to adjust the current. Thanks For Watching! Be sure to check out my video playlists.

[@ibrahimsahin8440]

hi what is the safety protect diods capacitor Value ?

[@electronicsNmore]

Hello. I don't understand your question. Which component in the schematic are you referring to?

[@ibrahimsahin8440]

hi diod protection capacitor value?

[@mattmoreira210]

Do you intend building a switching one? :D

[@ulchevy]

Can you burn a 1/8 welding road with this welding machine?

[@electronicsNmore]

Not sure. I did not try. Using 1/16" works perfectly, 1/8" is really pushing it. The thicker rod requires more current and will make the MOT's/wiring much hotter.

[@MYNICEEV]

Many thanks. Got loads.

[@Harold2247]

Hello, my name is Harold, I'm from Dominican Republic, this video is very good and very interesting. thanks I have just one question what is (MOV)?

[@electronicsNmore]

An MOV is a metal oxide varistor. The varistor is designed to allow a certain voltage to pass, but once that voltage is exceeded, the MOV which is normally at a very high resistance, begins to drop. The bigger the spike in voltage , the lower the resistance becomes. At a certain point they "clamp". which is like a short. The purpose is to help protect the diiodes from transients. Thanks for watching. Check out my homemade inverter generator.

[@Harold2247]

Thank you very much for your explanation! Nice

[@uniukuyu1295]

electronicsNmore A straight forward explanation that has earned you a new subscriber.

[@electronicsNmore]

Thank you!

[@uniukuyu1295]

NP, I came just looking around at various mot welder schematics and I know what a mov is but I liked your way of explaining things.

[@felixcat4346]

I don´t believe you can use a led on an ac circuit. The led is a dc device. The neon lamp will work fine.

[@electronicsNmore]

Of course you can, if you know what you are doing. :-)

[@felixcat4346]

+electronicsNmore Let´s see if I have this right, so the the led will flash at 60Hz which is faster than the eye can detect. I like the idea of a MOV protecting the rectified side I would use a voltage regulator to avoid any voltage surges as well.

[@electronicsNmore]

Joseph Nicholas kzbin.info/www/bejne/iaC1eKGHqph-eNE

[@jerrypetri]

You can use an LED but it will only turn on for half the cycle.

[@ibrahimsahin8440]

0.22uf ore 0.2uf ?

[@suribabusangadi124]

Good welding

[@electronicsNmore]

Suribabu Sangadi Thank you! Many excellent videos on this channel, so be sure to check out my video playlists, rate thumbs up and share.

[@GAMININISHSHANKABANDARAnish]

if i use bridge rectifier how to select Amp 100A,200A i have 75V 66000uf capacitor it can use this one

[@electronicsNmore]

That capacitor is fine. Use a rectifier from a large alternator. Thanks For Watching.

[@berthaimona6909]

Can this welder run off 230V mains like it is ? or should there be modifications?

[@electronicsNmore]

The (2) 120v microwave oven transformer's primary windings need to be connected in SERIES, not parallel. Make sure the transformers are identical and properly connected in series.

[@prakashgaming4742]

portable welding machine me o/c outo cut ka problem ka solvetion bataye Hindi me