since an unregulated alternator is capable of producing more than 100 volts of dc. power, this seems like a good way of getting yourself killed. I strongly advise anyone to check this out thoroughly before building/using this rig. John D.

 

But how many amps does it produce if its producing 100 volts

 

Amps is what will kill you, not volts.

 

John Amps x Volts is what kills.

Case in point grab the two terminals on your battery, If ya grab the passenger side batt you have almost 2000 amps running through you, but you'll never know it.

Tasers on the other hand operate to almost 30,000 volts but are generally not lethal due to very very tiny amounts of amps.

 

I am not going to argue the point, just talk to someone you trust (that KNOWS) before doing this. John D.

 

All a welder is is a generater either ac or dc. They have been using onboard welders for years the reason you have insulation on the stinger is to keep from being lit up.

I have never been lit up with a dc welder now ac cracker boxes and miller roughnecks are a different story but it was my fault every time.

 

Just grab them battery posts when they are wet. (NO DON'T DO THIS, just an expression) You'll know what I mean when it feels like you just got hit in the chest with a sledge hammer. (the water reduces our resistance through our skin and increases the surrface are at the contact points and just the right touch will stick you on the ground.

Also, Youll never have 2000 amp load @ 12 volts go through you, impossible. That would blow your arm off. Thats 24,000Watts of energy or about the equivent of 32 horsepower or 200 amps at 120 volts. Even then Our bodies have too much resistance to put that kinda load on a battery. Go put a starter cable across the terminals of your batterys and as it snaps, fries and the rubber burns off, try to expain that kind of current going through your body. The reason the cable burns and puts a large load on the battery is cause it has almost no resistance where our boddies have several hundred thousand ohms if not in the megaohms when dry.

The starting system has access to 2000 amps for example but it may only pull close to that right when you hit the key, the rest of cranking time it may pull about 300-700 amps depending on the loaded down voltage, starter, and engine compression. No other load on the vehicle pulls even close to that 2000. The load we put on it is less than your dome light takes.

AS FOR THE ON BOARD WELDER, It sounds like a great Idea. I keep an onboard welder with me but way different setup. I have an AIMS 5,000 watt (10,000watt peak) inverter I carry which produces 120 volts ac with a modified sin wave. I then just plug my Lincon mig 135 amp portable flux (or gas if you want) welder into it and it works great. It will also run my hand grinders and drop lights. It works great but a little bulky for some people. I also keep a small acetline torch kit as well.

Ultimatly, Im going to have to try that alternator conversion cuase if it works then I could sure use that on my sidekick.


AND JUST TO MAKE THIS POST LONGER, HERES A SMALL WELDING STORY.
Me and a few friends were out with my parents welding truck one day welding fences inside the pig barn for FFA. They are several cment stalles with metal doors on each one. Well, I had been welding up all the clamps on all the doors and had my ground set at the very front of the barn since all the gates were attched to a metal frame. Well the barn was very wet inside so I had thick gloves on and was welding away when my arc all of the sudden quit. I heard some commocion while I was trying to restart my arc and when it wouldn't, I looked up and one of my buddies was on the ground in a puddle of water on the floor and the other guys whas trying to get him to wake up it looked like. Finally he came to and asked him what happend and he had taken the ground clamp off with his wet bare hands while standing in wet shoes in the water where a metal strap ran the lenght of the floor in the center of the building. When He pulled it off, He was the now the circuit. He said it felt like getting hit by a truck and it took him forever to recover his breathing, it litterly knocked the breath out of him. OOPS, not a good Idea.

 

As for this, its impossible to know if you don't have a second variable such as the resistance of the load, watts, amps ect. It could be 10 amps to 80 amps on up depending on the altrnator and how big of load is applied.

 

It will only put out as many amps as the alternator you use will produce but as was said will very with resistance. The alternator I plan to use is only a 66 amp alternator not the best for wilding but it will be super high frequincy wich will alow a decent weld at that amp, the best part is it should only me around $250 to build the way I want it depending on how cheap I can find a spare alternator.

One thing i dont understand about the way he does it in the second link I posted is why he removed exciter diode, I don't see the need for this. any thoughts?

Amperage is most definately what kill but that being said the higher the voltage the lesser the Amperage required to kill. And even a very low amp and low volage shock can kill under the right circumstaces. It is much harder to get shocked by dc voltage than AC voltage. As an intresting side note: In the early days of electricity Thomas Edison would go around shocking animals with DC voltage to discredit Nikola Tesla and scare people away from AC voltage. This welder won't be any more dangerous than a 220 shop welder. But yes I agree it has the potential to kill you just as a car battery does and proper welding safty should be used.

As for the welding with batteries I dont want to cary bateries or drain the one in my vehicle down posibly leaving me in the same situation as with the broken part i am welding. Also battery welding is ver dangerous as batteries vent hydrogen gas, mostly when charging but the possibbilty still exists, and could explode due to stray sparks. Space is at a premium in my jeep wich is why I'm going to try to use one alternator as a welder and alternator. If it doesen't work the way i'm thinking it would i will just mount the voltage regulator out side the alternator.

 

Festus maybe if we had more Shellbacks in there we would be better off. I did 20 for Uncle Sam and now work in the oil field

 

It only takes 1/2 an amp through your heart to kill you.

 

Been along time since I seen/heard that word!

You Navy?

-Enjoy
fh : )_~

 

I was talking about this mod to someone today, they used to have a 24 volt alternator on their off road rig set up like that.

He said at 2000 to 2500 RPM he could burn rods as well as any 200 amp DC welder out there.

 

Yeah from what I've read you thats because its super high frequincy and it sure sounds like it when some one strikes an ark with one.

Any one know why i would need to remove the capacitor? on the older delcos like i have thats what people seem to be doing. My guess is they wont handle the voltage.

 

I seem to remember hearing that the AMC eagle 4x4 station wagon was available with an AC inverter that was powerful enough to run a small suitcase wielder.

I've been buzzed by 110VAC when I was something like 10 once and all it did was vibrate my finger a little. Never been shocked by a mig or tig wielder, (AC aluminum or DC steel) but heard it can be uncomfortable.

I don't think its out of line to run a light wielder off of an 150 amp alternator and a HD AC inverter, but I doubt you will be able to wield 1/4" material or thicker reliably.