Onboard Alternator Welder Writeup

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1973Guppie

1973Guppie

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So, I know to many this is old technology but thought I would try it out as I had a space where my unused york was sitting and thought it would be cool to have a stick welder on my FJ40. Plus, I didn't want to spend the ridiculous $$ to buy an aftermarket onboard welder. All in all, I spent about $150 and this could be done for even less if you were to get a junkyard welder. I just decided to purchase a 100 amp reman unit from the local parts store. I then had to buy a little scrap c channel, positive stinger from harbor freight, negative cable from harbor freight, an led switch and some wiring. Super simple setup, hardest thing was the bracket setup. Basically the alternator is an externally regulated alternator from a Ford. You need to put one wire to the "field" tab on the alternator and wire this to positive / fused source. This "energizes" the alternator. The switch is there so there is not a constant power source going to the alternator. Flip the switch, attach the cables and weld. Let me know if anyone has any questions!

Noah

first pic is the old york area cleaned up, the alternator is mounted where the AC compressor used to be, this is a 99 vortec engine.
alternator FJ40 welder 002.webp
 
My welds were not pretty, this is my first time stick welding, seems like you really need to move the rod at the begginning or it just seizes up? I finally was able to run a bead but it seems like a very thin bead, BUT it was hot enough as at one point it blew threw 1/4 plate. Any tips on welding with stick? Should I not expect a wide bead or does one need to move the stick back and forth, like an S all the way down? Any tips appreciated. This project was more for fun than anything, i don't plan to use the welder on anything but for emergency reasons on my truck or others, but I figure it is a good thing to have and it was fun to build.

Noah

Part #'s at Harbor Freight:

Item # 02715 electrodes
Item # 03720 ground clamp
Item # 46196 stinger / electrode holder
alternator FJ40 welder 016.webp
 
thanks, appreciate that, :)

the welder IS the alternator. I have 2 alternators mounted on the serpentine belt, the stock GM alternator and then the FORD one I added. Basically the ford unit is not regulated, meaning it does not have an internal regulator like many modern alternators do, therefore being a high output 100 amp unit, when you rev the engine it puts out whatever max output it can put out. Positive stinger goes to positive post on the alt, neg cord clamps to the work and to the negative post on the alternator and you complete the circuit by touching the rod to the work.....does that make sense?

Noah
 
what size rod are you using ,1/8" or 3/32" LH 70 you can run 1/8" at 100 to 110 amps 3/32" at 80 to100 amps . 1/8" 6010 at 100amps it burns hotter then LH70.
 
part or referenece number for the alternator?
 
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