Small 110 Volt Arc Welder (NYDG)




About: Former United States Navy Corpsman. After my service, I received a biomedical engineering degree, with a concentration in tissue engineering, from Drexel University. I enjoy reading, cooking, working out, bi...

Im going to write a ton of Instructables on how to make Not your Dads Garage but work area designed for the future of builders. I will work in an evolution process to more and more complicated project, using project in past Instructables to help current project, assuming you have access to your dads tools (Hammer, Screwdriver, Saw, Drill,)
We will start by making a 110 Volt Arc Welder, 220 would be nice but most Instructable starters dont have a 220 outlet. It needs a little solder so you will need a soldering iron.

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Step 1: Building the 110 Volt Arc Welder Housing

Make sure its strong, it will way more that 100lbs
1. 2 x (30 inch x 24 inch x 1 inch) SIDE
2. 1 x (25 inch x 36 inch x 1 inch ) FLOOR
3. 2 x (24 inch x 36 inch x 1/2 inch) Levels
4. 4 x (36 inch x 4 inch x 1/2 inch) Walls
5. 1 x (37+ inch x 2 inch Dowel) HANDLE

Step 2: Electronical Parts

I have had the best luck getting microwaves from Secondhand stores, for free or less than 5$ each. But you could check the junk yard, and other places, just dont break yours for the parts (popcorn is better than a welder).

Electronic Parts
1. 10 x Microwaves @ 900+ Watts
2. C1: 600pf 2kv ceramic
3. C2: 0.1mf 400v epoxy
4. R1: 1M Linear potentiometer
5 .R2: 5k Linear potentiometer
6. C3: 22mf 250v electrolytic
7. Q1: IRKT71 SCR module
8. Q2: Lamp dimmer triac
9. BR1: RB152 1A bridge rectifier
10. D1: Trigger diac

1. Wire Cutters
2. Wire Strippers
3. Soldering iron
4. Drill
5. Basic screwdriver set
6. Elbow Grease

Step 3: Moding the Transformer

Microwave oven transformers are step up transformers. That means that the voltage at the secondary winding is higher than the primary 120 volts. The secondary voltage is typically 4000 volts. Replace low voltage winding with #6 Single conductor wire, about 10-18 wraps. The load will change to 10 volt, and during welding will be about 2-4 volts at 250 amps.

Step 4: Electronical Parts

Assembling the Electronic Part onto the Caring Case.

Just follow the Schematics and make sure you get all the (step transformers) in the correct placement.

Easy to follow Schematic... Thanks too...., with minor changes.

Step 5: Finished Product

Special thanks to my electronics college teacher for giving me the idea and the special thanks to the web for donated material, pictures and information. Remember safety.

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    81 Discussions


    Reply 7 years ago on Introduction

    no the rads come from the emitter and it is not gama it is microwave waves
    simple chart i use


    Reply 10 years ago on Introduction

    gamma rays? that would mutate the food. now i'm off to "shoot gamma rays at food."


    Firstly, what are "Gama Rais"? Secondly, the microwave transformer does not give off anything but electricity and a little bit of heat. Thirdly, if you mean microwaves, the magnetron is what makes them and drools them into the cooking chamber.


    Reply 10 years ago on Introduction

    The transformer puts out plain old electricity, it's the 'magnetron' that puts out the microwaves that cook the food.


    7 years ago on Introduction

    I don't mean to be critical, but the project can be built a lot simpler. If you take a MOT (microwave oven transformer) and test the turns ration you'll find it's about 1:18. Turn it around and it's 18:1. So if you start with 120V you'll be stepping it down to 6V (measure it with a volt-meter, carefully!) Yes it will be AC but arc welders typically have a DC and AC mode. You can add a bridge rectifier for DC if you want to. Two reversed MOTS with parallel primaries and series secondaries will give you 12V output. Yes you can add more MOT's for more current output. Using a dimmer switch will reduce your power output because dimmers only use the trailing half of the wave, and dimmers don't really like inductive loads. They create "noisey" spikes that tend to heat -stress transformers, but only on half as long.


    8 years ago on Step 2

    I like popcorn but I disagree that popcorn is better than a welder. Popcorn is nice; welders make nice stuff. Nicer than popcorn.


    8 years ago on Introduction

    so to make a welder i only need an instructible on how to build a soldering iron :)


    Reply 8 years ago on Introduction

    These are my transformers, the top ones are the secondary and bottom ones primary or is it the other way around?


    Reply 8 years ago on Introduction

    Yup, thats right. The top coils are the secondaries, which you need to slice off. The bottom coils are the primaries, which you should not touch or damage in any way.
    Good luck!


    9 years ago on Step 2

    did that just say 10 microwaves? lol


    9 years ago on Introduction

    This is a little confusing on how to make it because 220 do the same thing on how to make it and I don't get what you are doing different can you help?


    9 years ago on Step 1

    Wait, so what sort of material did you use for your Welder Housing? It looks an awful lot like you used wood...


    9 years ago on Step 4

     the outlet for the owen in your kitchen is much hier amps, maby 40 amps.


    Reply 9 years ago on Step 4

    thanks dynamodan, I saw your site before this instructable and I recommend it!, its much clearer I believe.

    thanks to Kdemon too for sharing that info here!