View Full Version : Welder from Car altenator
10-22-2009, 12:07 PM
Saw this before on a 4x4 forum.. If it works for welding, it is a 3phase excited coil altenator, to use it for this purpose you must either have a older model with a external regulator or bypass the regulator inside.
I want one of these on my wrecker, along with the school bus air compressor/tank..
Anybody converted the "regulator GM alternator" to this here?? I pulled one apart, the brush holders is also the regulator. have to make stuff to hold the brushes? got a drawing?
If it welds, it'd also burn bolts out, be mobile. Also able to boost the wrecker or anything else around it.
During the blizzard here of 93, I installed a older alternator on my hotrod 64 El Camino, ran it at 4,000rpm, used the output to run a skill saw and cut wood for the stove. It was putting out about 90 volts, I had the van next to it tied to it with booster cables. The output can be controlled as easy as a resistor rheostat in the field circuit. These are also the best for windmills. THE skil saw never got hot, or ran on low voltage. I was very aware of it and kept sniffing it.
People in the neighborhood heard the skil saw running, we had been without power for about four days and they were wondering how we had power.
Looks like the one I had on the el camino for a day.
10-22-2009, 12:18 PM
Nope, but here's someeone who built one using a 100 amp alternator on a vertical shaft engine.... http://machinebuilders.net/forum/forum_posts.asp?TID=5225&PN=1&TPN=1
Many moons ago, one of the mechanics I worked around was retailing an aftermarket kit for GMs that converted from charging duties to welding with the flip of a switch on a panel.... I can't recall where he was getting the kits...
10-22-2009, 01:28 PM
Typical gm alternator which I have a half dozen of..
Note for wind power or welding generator you can bring all the working parts outside.. the regulator.. etc..
for wind mills, you bring the ac before the diodes down into the house. Excite the brushes according to wind speed.
Neat part here, this shows the brushes.. FOR wind power, or externally output control you'd break the regulator loose and bring them outside to the rheostat to control exciting current.
10-22-2009, 06:18 PM
Here you go Dave. I built one based on this guys instructions for off road truck about 7 years ago. It burned rod, and did a pretty good job, add a locking hand throttle (about $30 from napa) and you had current control via idle speed. IIRC I used a ~120ish amp alternator for a mid '80s buick diesel. I eventually needed an alternator for some project, and rarely used the "weldernator" on the trail, so I returned it to alternator duty.
Here's the link: http://www.geocities.com/Yosemite/2472/obweld.html
10-23-2009, 02:31 AM
I have one, in my land rover.
Being into electronics I first tried a couple or regulator circuits, but in the end didnt bother with them, I just shorted the pass transistor in the regualtor module, and connected the output of the alty to the rod holder, easy mod only takes an hour.
Welding current is controlled by the idle speed of the engine, and being DC the thing works really well.
The alty is a 200 amper from a ford scorpio.
I connected the + from the welding alty to the + input on the wirefeed on my mig welder, and it worked on that too, when I get round to it I'm gonna mod one of those cheap sip mains powered mig's to work with the alty welder, so I can have a mobile mig.
10-23-2009, 03:55 AM
Thanks for the linkie.. UGLY, but cool huh?
Pretty much what I got in mind for a sled-mount for the trucks. I got a huge winch I'd like to power with a engine too. I be thinking.. (danger will robinson).. but.. I'd like hydraulic on the winch. A pair of quick connects off the pump-welder-air compressor. And still be light enough to swivel up onto a truck < 500lbs.. with the cherry picker rig.
Probably will try to build a bolt burner too out of this power supply.
10-23-2009, 02:22 PM
Kinda looks like your robot lawn mower. You going electric now?
10-25-2009, 12:23 PM
I remember an article in the Mother Earth News back in the early '80s where they used an automotive alternator and a lawnmower for a cheap and easily portable welder.
Yup, just found a link:
10-28-2009, 10:50 PM
Didga see this one?
I have somewhere a big honkin Delco alternator from a GMC semi,bout 160 amp,huge diodes and a case about 8" round.If you want it I'll see if I can find it.
10-29-2009, 07:28 AM
Darin: Thank you.. I got one of them off a school bus. OKAY, for that I am going to build a small tower and put it up with blades.
ON the ac output coils inside, there are three of them wires (3phase) I will use a coupling transformer tied into a zener clipping circuit to provide a clean 5v ttl pulse.. only a very few parts, regulate the commutator current according to "pulse" indicated wind speed rpm.. add power to Brake or slow blades.. this way it does not take a strong wind to generate power as with permanent magnet rotors they are installing in them. This generated "CURRENT" is only going to be good to wire into a oil filled heater to heat with. NOT run a tele or anything else voltage "RANGE" critical. Do you need heat down there? want to build a battery bank-storage unit? battery hysters are cheap at auctions, usually don't work, but come with battery and charger.. the perfect home auxillary power source. Sometimes one or two dead cells thou. BLOW the tar off them, replace the dead parts, do not retar them since it is not mobile and shaking.. (unless you live in California)
On all the internal regulated altenators? you can bypass the regulator by soldering a wire on the brush output wire to excite the fields. Thou I have not done it yet. It may be too close to the plastic. I have five or six of them around, one I destroyed disassembling it. (give a big man a hammer for a second) It did however come apart.
MY experiment to come, and I got two experiments on the kitchen table is the edm directly off the altenator. That very old gantry plasma-torch cutter is on the table right now. I had to run the mice and spiders away from it.
10-30-2009, 11:11 AM
Darin: Others interested?
Removing the GM internal regulator from the altenator? You see two bolts, one going through the brush holder to case GROUND, other is bolted to the regulator module in behind the brush holder.
Put A SINGLE wire there on the positive brush holder screw, a ring terminal and run the wire out the back. The regulator then can be "HOT WIRED" in bypass mode to put out 100%.. I'd make sure I had it dissconnected from the car alternator circuit, since this would blow about everything voltage sensitive on the auto.. but.. YOU would have 100% output by just energizing the positive brush holder.
Since I don not need regulator use normally? I will bypass that with the wire.. two toggle switches, or one large double pole single throw switch to ENGAGE or BYPASS regulator. (switch in Power, switch out car, switch in output to edm, welder, etc.)
After I get about a dozen bolts burned out here, well I am starting on that windmill maybe next, it is getting cold and I can hear that power meter spinning.
I have tore apart three alternators now.. Out of 5.. and found wore out brushes in each of them.
11-3-09,,, make that 4 out of 5... I got a pile of junk here.. man.. coils are good, bearings are good.. brushes are all crapped out.
$5.99.. am I being cheap or what?? Oreillys auto parts.
11-12-2009, 11:17 AM
By the way, the twist lock here.. I will untwist the milling machine spindle motor, twist lock this in.. I was actually afraid trying to edm there knowing one "ttl" flicker and the spindle might come on beating me, or dragging me into the spindle with the flipping wires.. This is a 3phase motor, varying speed, or varying field input will make the output go up and down as I desire to "add too" the edm power.. hook in on top of the lil transformers and other capacitors.. this outputs about 90 volts or so running wide open on 12 volt fields.. this is a pre-internal regulator alternator.. smaller output.. but.. I will modd another to bypass the regulator, when I get some more brushes..