I've found two ways of making an onboard welder... which begs the question, which is "better"? Not worried about which is cheaper.

In the first, Jeff Fretwell (http://www.pirate4x4.com/tech/on-boardwelder/index.html) uses an externally regulated Ford alternator with a 110-volt power supply(Napa P# 782-1757). Can someone explain what the 110-volt power supply is doing or provide a wiring diagram for this? What is the "optimal" vehicle to snag one of these from? Would it be worth the money to have the alternator I grab professionally rebuilt and the power beefed up?

In the second, Jon (http://www.huv.com/jon/jeep/Welder/on-board-welder.html) uses a GM-Delco alternator that he removes the exciter diode from and removes insulation from the voltage regulator. He mentions that the alts are used on "most GM vehicles, and Jeeps". Would one from a "late 80's" GM vehicle work(I thought they are CS130s)?

Anyone else have some good instructions for making an onboard welder using either GM or Ford alternators? I'm not going to be using it for charging purposes.

Lastly, anyone know of a way to retro fit a homemade onboard welder to use flux cored wire? (More of a convience thing than a functionality thing <IMG SRC="smilies/tongue.gif" border="0"> I've got the Century porti welder for the back up welder)

I went with a 90A Ford large case alternator for $15. I would have snagged a CS130 Delco or a Ford 105A if I could have found one at the Pick N Pull. Bigger is better. The 90A is good enough to run all 3/32 DC rod with no problems. It is a little tricky to run 1/8 inch electrode and you need to run it at a higher engine RPM. A smaller diameter alternator pulley would help.

The NAPA box is apparently a dual voltage regulator: 14 V and 110 V DC. I skipped it. You can also regulate the voltage by the engine speed.

I'm sure that you could run flux core wire if you could fab a reasonable spool gun.
http://members.home.net/cglabe1/Air/Air.html

Originally posted by Pin Head:
<STRONG>I went with a 90A Ford large case alternator for $15. I would have snagged a CS130 Delco or a Ford 105A if I could have found one at the Pick N Pull. Bigger is better. The 90A is good enough to run all 3/32 DC rod with no problems. It is a little tricky to run 1/8 inch electrode and you need to run it at a higher engine RPM. A smaller diameter alternator pulley would help.
</STRONG>

So, relatively speaking, you were happy with the performance of the 90amp Ford unit?

Any ideas on what I vehicles I would be looking at for the 105 amp Ford unit?

I've got a few local pick-n-pulls I can run through in about 4 hours <IMG SRC="smilies/tongue.gif" border="0">

Originally posted by Pin Head:
<STRONG>The NAPA box is apparently a dual voltage regulator: 14 V and 110 V DC. I skipped it. You can also regulate the voltage by the engine speed.
</STRONG>

Ahhh.... I suspected as much about the NAPA box... just a "toy" Jeff added for running grinders and such <IMG SRC="smilies/tongue.gif" border="0">

Thanks for the input... anyone else?

So far, the 90A has run 3/32 rods with a good duty cycle (maybe 3 rods in 10 min before it gets too hot to hold your hand on). That should take care of almost anything you are likely to encounter and then some if you do multiple passes. The large case Ford 105A was found on police, ambulances and some taxi cab crown vickys from the 70s to mid 80s. Part # begins with 105A. I got the 90A off of an 82 Lincoln continental. T-birds have them too. Any Ford large case alternator can be upgraded to 105A for pretty cheap which is what I'm going to do if I ever burn out the 90A: http://www.alternatorparts.com/ford_alt_repair_upgrade_kits.htm

The Delco CS130 is also a great alternator, but you will have to remove the internal regulator as described in Jon's page.
If you want to run 110 V brush type electric tools or light bulbs, you can just put a couple of plugs in, a voltage meter and regulated it by engine speed.

I read something about how Bosch rated there alternators different than the others and a 40 amp Bosch alternator put out more current than a 90 amp Ford alternator. Maybe it was ona mobiweld page or something because they use the bosch stuff. Anyway, bosch can make some good electric motors. I wonder if anyone knows the details of this, or has used a Bosch alternator for a welder.

So if you hook up a bracket and then the ford alt... How do you attatch the electrodes? Pix?

Originally posted by Just make it stop Skyetone:
<STRONG>So if you hook up a bracket and then the ford alt... How do you attatch the electrodes? Pix?</STRONG>

From what I have read, it is a three wire hook up.

The electrode holder for welding is connected to the battery output on the alt.

The ground for welding is hooked up to the alt case.

Then a switched 12 volt wire goes to the field pole hookup on the alt. When the wire is hot, you can weld <IMG SRC="smilies/tongue.gif" border="0">

I haven't seen a picture of a Ford wired up or even a schematic so I'm not sure where the field pole is. The web site by Jon above shows a wiring schematic using an AC delco alt. Pinheads web site shows the alt but not any of the wiring <IMG SRC="smilies/frown.gif" border="0">

Hopefully, I'll find out in a week or so <IMG SRC="smilies/biggrin.gif" border="0">

From what I have read, it is a three wire hook up.

The electrode holder for welding is connected to the battery output on the alt.

The ground for welding is hooked up to the alt case.

Then a switched 12 volt wire goes to the field pole hookup on the alt. When the wire is hot, you can weld


Yes, it is that simple. Note that you can run the electrode and ground in either polarity AS LONG AS YOU ARE NOT WELDING ON THE SAME VEHICLE as the welder is in. When you are welding on the vehicle with the welding alternator in it, you can only run electrode positive (DCEP) or "reverse" polarity.

How about an Externally regulated GM alt? Would that work the same as the Ford as a welder?

I'm in the process of doing the same thing on my XJ, so maybe I can be of a little help.

The Napa regulator is a nice little toy, but isn't needed. If you are going to run a single alternator, you need it to regulate voltage for the charging system, and then it can be switched into "welding mode" and also allow the use 110v outlets. This makes repairs easier since you can run your grinder, saw, lights, etc. If you are running the welder as a second alternator, just regulate the voltage with the engine speed. The stinger goes on the battery output, ground clamp to the case, stike the arc and away you go. The beauty of this project is that it can be hillbilly simple, or Bill Gates complicated, either way it works.

I still haven't found a decent alternator to use in mine, thus everything is still on paper and mockups in my shop until I get off my butt and find the "heart" for my system. I reccomend looking on E-bay for cheap externally regulated alternators with high outputs. Newly rebuilt 140A units can often be had for $40 or so, which is a good deal considering the time you save. My local PNP asks way too much for old alternators that they can't even guarantee work, so I will probably go the e-bay route eventually.

Like I said, this can be as complicated and packed full of features as you want it to be, just use your imagination. If you don't know jack diddly about basic electronics, you might want to get a book and give yourself a little into before you attempt something too elaborate. Good luck, and be sure to post lots of pics.

Well hell I have like three old 70's GM v-8 90a? alts sitting under my house. Aren't they x-regulated? Old shit is cheep. hows about a disiel alt or something? Aren't neyer sports cars higher amp? shit don't make me search....

Most of the GM alternators from 1971 to 1985 are the internally regulated Delco 10si models from 35 to 65 A. 80A was an option on some vehicles like police cars. These alternators can also be cheaply upgraded to 105A, but you will have to remove the internal voltage regulator for welding. http://www.alternatorparts.com/gm_alt_repair_upgrade_kits.htm

Originally posted by Just make it stop Skyetone:
<STRONG>Well hell I have like three old 70's GM v-8 90a? alts sitting under my house. Aren't they x-regulated? Old shit is cheep. hows about a disiel alt or something? Aren't neyer sports cars higher amp? shit don't make me search....</STRONG>

i have found this site very helpful

http://www.transpo.de/

Looks like my luck took a change for the better <IMG SRC="smilies/smile.gif" border="0"> I found a large case Ford unit that was 100 amps and recently rebuilt <IMG SRC="smilies/tongue.gif" border="0"> Paid $20, had it tested, and it is good <IMG SRC="smilies/eyemouth.gif" border="0">

I've almost got my brackets made up and painted(all of 9 hours from finding/pulling alternator to making and painting brackets.... with a LOT of rest time) Amazing how much crap you can pack onto a TBI engine: smog pump, york onboard air, PS pump, stock alt, AND the ford alt/welder <IMG SRC="smilies/biggrin.gif" border="0">

I'm now looking at wiring it up <IMG SRC="smilies/eek.gif" border="0"> Pin head, I just wanted to verify that the field wire gets the switched +12 volt.

I've got "two" free wires on my alternator... one is labeled fld, the other is sta. I would assume the fld is the field choice... but what is the sta <IMG SRC="smilies/confused.gif" border="0">

Stator? <IMG SRC="smilies/confused.gif" border="0">

John,
Yep, the switched positive wire goes to the field tab on the alternator. I'm not sure what the stator wire does, but I suspect that it may light up the idiot lite. It welds without the stator wire hooked to anything. I had mine apart for a peek at the windings and the stator wire goes to a pin on the rectifier assembly. It is amazing how easy it is to add a second alternator. You should be welding in just a few more minutes. I'm toying with the idea of rewiring the stator from the original "wye" to the "delta" configuation to provide higher amperage and less heating of the case. This will boost the current by a factor of 1.72 at the expense of voltage output at low speed. This is what you want for welding. For $15, it is worth the experiment.

Check out the discussion of 3 phase alternators in the middle of this page: http://flthlpdsk.chinalake.navy.mil/SHIPS/shipeng/elecgen/elecgen.htm
and this: http://www.transpo.de/support/bulletin/bl99037.html

[ 10-16-2001: Message edited by: Pin Head ]

I'm lazy and have to put alot of shit together. Post finish pix and what did ya get the alt outa and how do you know it's big amps?

FYI, a good source for 100A (105A?) Ford externally regulated alternators is power-everything Tauruses (Tauri?), LTD's, Crown Vic's, and similar. They'll typically be a flat-belt design if they're new enough to be on a Taurus, but the pulley is cake to swap.
The pre-'86 (pre-flat-belt) cars didn't have the big alternators near as regularly--the new stuff has all kinds of electrical crap (fans, power everything, EFI) that takes lots of juice, hence lots of big alternators.

Originally posted by Just make it stop Skyetone:
<STRONG>I'm lazy and have to put alot of shit together. Post finish pix and what did ya get the alt outa and how do you know it's big amps?</STRONG>

I'll post a couple pictures later today once I finish mounting it up.... I need to get a new bolt, a bushing, and paint a bracket <IMG SRC="smilies/tongue.gif" border="0">

I pulled the alt out of a mid 80's Lincoln or Mercury. The case on it is VERY large as you will note in the picture I will post later <IMG SRC="smilies/tongue.gif" border="0">

so how big a rod can you use? Just a standard rod? That'd be K/A. Hell I may have to go to the P&P later this week and get one for like 20$ then it can sit next to my york waiting to get installed. Was thinking of running a single belt from the crank to relay to york to alt and back. If you covered the terminals I would guess running full time wouldn't hurt. BTW how to you get a lead for the rod? I would think that the standard welding lead would be WAY to huge. Then what A big alligator clip to hook to the pos? I guess I should read the other articals hu <IMG SRC="smilies/biggrin.gif" border="0">

Here is how I've mounted my alternator:
<IMG width=421 height=261 SRC="http://www.pirate4x4.com/ubb/uploads/lj_mount1.jpg">

<IMG width=482 height=296 SRC="http://www.pirate4x4.com/ubb/uploads/lj_mount2.jpg">

In the first picture, you can see the stock alt on the left(small one), the Ford alt in the middle, and the York on the right. When I was picking up the Ford alt, I found several Fords that were of the same size as the one of the left.

In the second picture, you can see how much thicker the Ford alt is when compared to the GM alt.

Here are a couple of views of the alternator itself:
<IMG width=432 height=299 SRC="http://www.pirate4x4.com/ubb/uploads/lj_alt1.jpg">

<IMG width=323 height=256 SRC="http://www.pirate4x4.com/ubb/uploads/lj_alt2.jpg">

<IMG width=344 height=272 SRC="http://www.pirate4x4.com/ubb/uploads/lj_alt3.jpg"> <IMG width=343 height=271 SRC="http://www.pirate4x4.com/ubb/uploads/lj_alt4.jpg">

In this last picture, you can see where all the wiring will go. The "big" red post is the positive stringer. The item labeled ground is the negative stringer. And one of the two spade connectors is the field which gets a +12V when you want to weld.

Thus far, I have about $25 in the project. I had scrap steel for making the brackets. Tomorrow, I will be picking up some quick disconnects and the wire for the stringers.

Originally posted by Just make it stop Skyetone:
<STRONG>so how big a rod can you use? Just a standard rod? That'd be K/A.
</STRONG>

From the look at rods I saw at Orchard, I think 1/8" rod would be too big for a "small" 100 amp unit.... from what I recall the minimum amperage was either 90 or 100 amps <IMG SRC="smilies/frown.gif" border="0"> I might give them a try to see what happens when I get back up and running.

Originally posted by Just make it stop Skyetone:
<STRONG>BTW how to you get a lead for the rod? I would think that the standard welding lead would be WAY to huge. Then what A big alligator clip to hook to the pos? I guess I should read the other articals hu <IMG SRC="smilies/biggrin.gif" border="0"></STRONG>

I intend to run just a standard welding size stringer and ground clamp(I believe they are about 4 to 0 guage wire). It would simply take a good lug and a cover over the positive terminal. I'll be picking up this stuff tomorrow <IMG SRC="smilies/biggrin.gif" border="0">

Looks sweet. Did you spark it up yet? Part of the reason that it is rated at 100A is the smaller pulley to drive it faster. The pulley on mine is almost 3 inches. It will run all 3/32 rod and 1/8 rod too if you have a steady hand. So far, I have just used 4 gauge jumper cables as the welding cables, but they are a little short to be welding on you rear spring hangers. Here is a picture of mine mounted on top of the York. It fits under the hood with it closed.
http://members.home.net/cglabe1/Air/Air26.jpg

[ 10-17-2001: Message edited by: Pin Head ]

Originally posted by Pin Head:
<STRONG>Looks sweet. Did you spark it up yet? </STRONG>

Thanks.... still have a few things to finish up before it gets fired up <IMG SRC="smilies/frown.gif" border="0"> New belt, new thermostat housing, and new upper rad hose(the new housing is the only thing that ticks me off a little)

I'm going to take care of wiring it up tomorrow after I get some of the parts above plus a couple of misc wire fittings. I may also stop by the welding store and pick up the rest of the goodies also <IMG SRC="smilies/biggrin.gif" border="0">

Still amazes me the amount of junk around my house that I've found will working on this project: Wire all over the place. A GM style water proof fuse holder. A lighted switch. Angle iron, flat bar, etc. Aside from $20 on the alt, I've spent another $5 for a spacer and bolts for the york <IMG SRC="smilies/tongue.gif" border="0">

Originally posted by Pin Head:
<STRONG>Part of the reason that it is rated at 100A is the smaller pulley to drive it faster. The pulley on mine is almost 3 inches. It will run all 3/32 rod and 1/8 rod too if you have a steady hand. So far, I have just used 4 gauge jumper cables as the welding cables, but they are a little short to be welding on you rear spring hangers.</STRONG>

I should be ok... when money allows, I might just haul the alt into a shop and have them build it up <IMG SRC="smilies/smile.gif" border="0">

If my luck holds, I'll give it a test this weekend while I do some rocker guards for my Taco <IMG SRC="smilies/biggrin.gif" border="0">

Originally posted by Pin Head:
<STRONG>Here is a picture of mine mounted on top of the York. It fits under the hood with it closed.</STRONG>

My york higher than the alt and off to the side... it clears the hood with about 3-4 inches <IMG SRC="smilies/eek.gif" border="0">

Your web page has helped a bit... more information added to everthing else I've found.

[ 10-17-2001: Message edited by: Lil'John ]