How to Turn Your Alternator into an Arc Welder 

If anyone is interested I have a video breaking down this mod step by step. Thanks Merlin for the diagram! I made a slight modification from yours as I added an external rectifier. I believe that will avoid the burnt diode that your alternator experienced.

I dont know if Merlin was a teacher at 1 point in his life if not he'd make 1 helluva teacher! Thanks for the videos you're a cool dude.

Merlin and Jimmy are becoming my favorite Sunday morning duo 😂

Just some things to add to this. There are two flavours of alternator delta and y. Delta are better at producing current You really need a control on your rotor. To control the voltage. Stick weld is not constant voltage but constant current. There is a circuit on line that varies the rotor voltage to keep the output current constant. The other thing is to use reactance on the out put cable. Just the weld cable rapped around a pipe. This will stabilize the arc by building a magnetic field if the arc breaks the magnetic field collapses and the high voltage will re light the arc. Lastly newer alternator diodes are made to blow with more than 40ish volts to protect the ecu in a car. Use an old bosh they are rated for full current and are delta wound. I’ve done this same thing and learned a lot Good luck.

I wish you would do one more follow up video here that's focused on how to run your "Welder alternator" like a regular welder again, with the external regulator and how to hook it all up correctly and how it should work, what all the wires do, etc.. That would be a perfect sister video to this one. I really appreciate you teaching this stuff, because most people like to keep these types of things their little secret. cheers.

Always enjoy learning new things, don’t let age stop you from growing, I’m 65 and love learning new things

i did not realize your diagram shows how to not only turn your alternator into a welder, but still use it to charge the vehicle... that was pretty cool =)

I bet you could go hundreds of how to videos. Thanks Merlin, going through my alternator’s right now.

I am a retired physicist who grew up in Eastern Oregon. My dad, and other WW2/Vietnam Veterans, taught us how to use electricity from the resources available, just as you describe, but in order to survive. My brothers and I were often Stuck, far into the woods, but made it home by understanding the incredible power connected to a piston engine via. generator or alternator, as Our Veterans needed to survive. You explained this PERFECTLY, RESPECT for the ingenuity of neccesitty! Dribbling gas through the valve stem to reinflate our tires was a very bad idea...but it worked 'Just Say'n (Huge Smile)

Had a buddy that had an Alternator welder run off an old Homelite Chainsaw, worked fine and a lot better than goofing up a vehicle. He used a rheostat too control the Imput too the Alternator rotor though the brushes, this is actually a 40 year old trick.

I sure would like to see a full install video from start to finish.

Wish my auto shop teacher was as easy to understand as you are. Great video Merlin!

I was introduced to this method of welder from my mentor at a very young age. He told a Korean war reconnaissance mission for returning a crippled tank. It had suffered a broken axle so he welded it up for it to be loaded on the truck. He also used a pickle crock to boost amperage and a set of jumper cables to finish the task. Thanks for sharing

Did this over 30 years ago. Taught myself to weld with the set up. Even repaired and got people out of the woods with it.

With a simple explanation the idea of approaching that myself is doable rather than daunting, thank you.

I worked at an alternator shop 30 years ago and built one for my landcruiser. I used the big case ford off an off a LTD. They hold up better. Bigger heat sink. Worked great!

Very educational video Merlin, I had a conversation with my coworkers about how people were doing trail repairs using their alternator to arc weld with just a couple modifications to their alternator, they just couldn't believe it so now I will share your video with them, then they will finally get it.

Oh yeah! A bunch of us will be welding on the trail thanks to you!

Great video and great example of how to get it done I put one alternator on my truck for charging the battery and one for welding God bless from GA and stay safe

He asked about the phases: (I can't draw a sign wave, so I'll just use 'n and u") When you stick a single phase through the rectifier, it turns all of the negative AC pulses into another positive pulse; so then your signal likes like this: From AC= n u n u n u n u To rectified = n n n n n n When you have more phases, it will do the same things, but just at a slightly shifted time frame, and make the signal look like this: Single phase rectified= n n n n n n n n Only two phases rect. = nn nn nn nn nn nn nn nn Three phase rectified = nnnnnnnnnnnnnnnnnnn So it's the same things happening, there are just three of them happening slightly ahead of one another in time, which fills in the gaps between each pulse. Giving you a higher resolution of pulses, basically turning it into nearly a smooth DC voltage.. They could even put more phases and it would smooth it out even more, but that costs more money and isn't necessary, because 3 phases already smooths it out quite a bit... Very cool stuff-- I learned a lot here and I'll be building one. Cheers.

Amazing. Now let's see how you setup those cheap air conditioner systems in your vehicles you've talked about. Great stuff!

Excellent video as always!! Reminds me of my childhood watching my Dad weld a muffler on his 53 International pickup on the side of the road with jumper cables and a coat hanger. Please keep making videos and pass on your skills and wisdom to future generations. God bless you and yours!

Legit. Such a good piece of information, and a very good way to get concepts across to your audience. You use a first-person POV (real-time, from Jimmy) to make it happen. So good.

That was a incredible video my father was an electrician and in his old 1966 GMC K 2500 he had an outlet for running AC power tools very similar to what you just showed us minus the welder. Keep up your awesome content absolutely love you channel, Thank You for what you do on You Tube 👍

Over 30 yrs welding and I'm impressed. Thank you sir!

That is cool I have welded with 12 volt batteries before but never with a alternator I got to say that is cool. Man you can have a alternator for a welder and turn a A/C compressor into a air compressor you can have a whole service rig running off your engine.

OMG... LOL... Safety at it's finest. Not to mention welding while work piece is clamped to a plastic milk crate. Holding work piece in mid air while my buddy grinds it and shoots sparks into my eyes. Love it

My X Father-in-law over 40 Plus year's ago built these to run off your vehicle. Sold thousands of these throughout the United States. Pretty cool concept

That makes it much easier for trail repairs instead of having to buy the vehicle welder that Paul uses. Much cheaper too.

Great video and very well done. Thank you so much for taking the time to get the information out.

Merlin the Magician comes through again ! Thanks for the tutorial. Outstanding.

Thanks you Merlin for sharing this it will be very helpful for me in the future.Keep the great videos coming!

We had a alternator welder in the 80's it worked great.

That was amazing thanks Merlin 👍🏼 that weld came out really nice

That was a fantastic lesson and something to have even if you don't go 4 wheeling. Thanks to all of you for sharing this with your subscribers & viewers.

I looked at vehicle mounted welder after seeing fabrats had one. Your way appears to be as good a welder but way cheaper, for me cheaper is good as it’s something I’d use but not a lot. Thanks for sharing it Merlin👏👏

I've been waiting for this video since you brought it up. That is amazing!!! Thank you

I like to learn something new every weekend. This might be the most useful so far. Thank,you.

WOW That's amazing Merlin thank you!

Thank you for sharing this. I have heard of it but never saw the schematic. You have done the DIY guys a big favor here. Thank you so much.

Awesome knowledge dump. Thank you Merlin.

Well done Merlin !!

That's bloody fantastic fella. Great tutorial, really easy to follow.

What I found funny, was a quick picture of a Palm Tree in the background, One guy is wearing only a TEE-Shirt, the other (Merlin) wearing first a hoodie sweat shirt, than put's on an extra coat. The poor women looks as if she's in Alaska freezing to death. Great video, very informative. Thanks for sharing.

Great information. Instructions are spot on. Understood the diagrams all the way. Bring more of these videos.

I remember about 30+ years ago my father did that to his truck, you plugged the welder in a connector in the grill also had a receptical there to plug in 120.

Thanks again for all of your content Have a Great Day 👍 God Bless You and God Bless America 🇺🇸🇺🇸🇺🇸🙏

Great video Merlin!! A lot of us dyi ers love this kind of stuff! Not sure I'll ever use this particular method but it's nice to have in the cupboard for "in case". Thank you for teaching this kind of thing!!!

Thanks Merlin! Awesome video, great for those trail repairs, helpful and complete, full of detail and very understandable, now I just have to get off my but and do mine!

Wow,thats awesome!!Thanks Merlin You're The Man...💪👍👍

Thanks, Merlin, that's awesome!!!!

MERLIN is the GOD of mechanics and AWESOME tricks..

Very good job. Nice teaching basics and to set up a welder on the rig u go off road in. Stay safe.

Awesome job!! Now I have another project!! Thanks a lot!!

EXCELLENT video, Merlin. Fun and educational plus the coolest golf cart on the planet. Thanks for doing this!!!

Merlin I’ve been actually thinking about getting one of those on board welder setups but was kinda not wanting to spend the money on one quite yet!!! I’m definitely glad that I waited and seen how you do them!!! I’ll definitely be trying to make myself a setup for my 1981 Chevy 1Ton 4x4 that way when one of my buddies breaks down on the trail and is wanting to call a wrecker to have it hauled back to the shop for a repair I will be able to just do it out on the trail!!! Awesome video buddy!!! Hopefully I can figure it all out and get it figured out Wright!!! Lol!!! Well thanks again and remember keep up all the hard work buddy!!!!

And this is why I'm subscribed to this channel! Thanks Merlin.

You are a wealth of knowledge and appreciate your information sharing and teaching. You clearly explain the workings, required changes and execution. 👍🇨🇦

That's awesome! Keep up the great work and thank you for the knowledge

Yes. See the light on above his head already 👍🏻👍🏻

I found a kit with everything you need to convert an alternator like that about 25 years ago. Never installed it, still out in the garage right now. lol. Super cool device, thanks for reminding me of this!

Wow Merlin, that is really cool that a person can convert a normal alternator into a stick welder that actually has some power and works. Your video, explanation of the why's and wherefor's of the process and your diagram will be helpful to a lot of people. I think I'll build one and put it on my van. The look on people's faces when I fire it up and weld something together will be priceless!

This was extremely easy to understand and follow, thanks for posting this Merlin 👌

Always so much good info from you. Love your channel.

Nice walk thru, I made one of these for my 87 Suzuki Samurai out of the 60amp Delco 10si. I made one for my buddy out of a Ford top post alternator. Good old "Weldenator."

That is awesome! I’ll have to watch a few more times. Thanks for this.

Awesome vid! I remember reading up on this welder set up years ago in 4wheel mags but never did one and have since thrown out 38years of my mag collection. I will be printing off what you gave us to print and utilizing it this time!

Its very cool 😎 seeing what is old technology being explained by a great teacher. Pay attention to people with this type of mind bc you will learn much!

how cool!!! Thankful you put out videos like this, now I am motivated to try stuff like this.

Very informative video!! Thanks for posting this

Thanks. I've been looking forward to this since you mentioned it. I'm going to do this to my Ford after Snowbird season.

Great teacher, Merlin!

Good stuff Merlin, thank you for sharing your knowledge 👍🏻👍🏻👍🏻

This video alone is worth a million subs man!!! 👊

Thats so awesome. Im definitely doing this to my jeep YJ..Thank You Sir. Great Video...

Pretty amazing tutorial. Can't wait to set one up.

That is cool, my dad's work truck had a welding alternater called high frequency. Instead of using high voltage to make heat it used higher wave frequency. Thanks Merlin Central California watching

Thanks for sharing your knowledge with us old school is the only school!

I know you learn something new everyday but dang this is worth more than the things learned in the past week! Thank you for sharing. From my view it looks like you are living the dream.

Merlin, you really are a wizard! Thanks for the lesson!

Awesome!!! So informative!

The mechanic everyone wants to be Could turn a brake caliper into a vice on side of the trail to hold a piece of metal so his (homemade alternator welder) cuts, welds and grinds to get him going again 👍🇺🇸

Merlin this is amazing! Thank you for the video and all the knowledge you shared

Brilliant solution.

You are a smart feller !! Thanks for sharing your knowledge. Good man .

That's awesome, thanks for all the great information.

I am impressed. Thank you. Your content is more than interesting. It's intriguing.

I agree with Jimmy, That is the coolest thing I have ever seen!!!. You always have great content Merlin , just super.

Great video ! Thanks Merlin

Been watching you for quite awhile. Absolutely great and educational.

Awesome video and explanation!!!! Super cool stuff

Excellent video and description with one flaw. The switch is a double pole, double throw. Not a six pole. Keep up the good work.

My welding instructor in HS has an old international truck, he had 2 altanator one for the truck the other was the welder I think. We all got to try using and he took us out to a farm to weld on some farming implements.

Pretty awesome Merlin, always cool toys and great information 👍 thank you Merlin

Excellent video. The only thing that threw me a bit is you called a Double Pole Double Throw switch a "six pole". So I was staring at your diagram trying to figure out the other four poles when I realized you are counting all the connections on the switch as a poles.

Man I wish I was your neighbor. The stuff I could learn from you.

I always thought you could do that, now I'm going to build it. Thank You

Thank you for the education and knowledge, Merlin. In this life I try to learn at least one new something everyday, you just took me to school.

This is the coolest thing! I wanted to put premier power welders on my jeep and my truck but really didn't want to spend the money... now I'm gonna go do this to all my vehicles, because why not?

Sweet Merlon ! Awsome video my man ! I wondered how to do it but now I can , thanks again !