John Deere welder....well, sort of

[Guidster]

You know what they say about necessity being the mother of invention. Well, for some of the things I want to build around the house, I need a portable welder--my MIG is not exactly portable. With the wife still tight on the purse strings from my recent tractor purchase, I had to come up with something. The answer was to build my own alternator based welder--and oh, boy am I glad that I did!

Ultimately, I intend to put it on my tractor, after I do some more design to allow for a weld/charge/accessory mode that will allow the same alternator to weld, charge the tractor battery and run grinders and the like. If I had more room under the hood, I would keep them separate, but I do not have this luxury. To serve as a test bed, I cobbled together a frame from scrap to hold the alternator on my JD L130, 23 horse mower.

I know that other have kits out there to do this, but they run much more than the $50 I have into this setup. It welds like a dream--burns 1/8" 6011 and 7018 with no worries and gets awesome penetration. I could not be more happy at this point.

I cannot wait to put it through its paces tomorrow. I will include a couple of pics that show my initial test setup that I will refine over the next week or so. Fun stuff.

 

[Guidster]

another picture of the business end of the welder...

 

[Guidster]

The results of my efforts. Top bead (1st one I ran) is 1/8" 6011. Bottom is 1/8" 7018

 

[Guidster]

one last one--different perspective of the "welder."

 

[bobodu]

Very clever!!
Outta be a stock item on them Deeres..."Physician..heal thyself.".. /forums/images/graemlins/smirk.gif

 

[RedRocker]

I have a Link Arc welder on my Jeep that I'm thinking of adapting to my PTO. Any ideas on how to turn an alternator with a PTO would be appreciated. I was thinking of some type of torque converter to vary the speed, or just a direct pully and use the throttle. I like your setup, pretty clever.

 

[fig]

Red,

I would think that you could find the pto adapter from a pto driven pump and cobble up something that could be used to connect to the alternator. Just nugget scratchen.

Fig

 

[Mike_C]

I would be interested in knowing how long the alternator lasts long term (of course you don't know yet). I would think that subjecting it to extremely high loads like that would tend to shorten it's life considerably. Even if the alternator is rated at 100 amps, I would think that when you initially strike the arc that the surge current is much higher.

 

[slowrev]

Nice job, Need to make a PTO driven one of those for portable use.

I almost bought a genuine John Deere Welder at a sale a while back, it went too high for a welder that I did not even know whether it worked or not though.

Ben

 

[Guidster]

I too am interested to see the longevity of this thing. The alternator is rated at 130 amps with brief surge capacity up to about 160 amps before the diodes pop. Time will definitely tell for sure, but I can't imagine that it would be any worse than installed in a vehicle where it is so dang hot and abused. This alternator came out of the boneyard for $25 and obviously has a lot of use under its belt. If this old alternator hangs in there for quite some time, I believe that I would then purchase a fresh rebuild using this as a core.

In regards to the surge current, I have used a clamp on ammeter from work and performed some readings while welding today. The amperage is actually at its highest when you get a consistent, stable arc started. It does vary quite a bit as you scratch the arc, but lower than when you are established.

I hooked up a convenience receptacle today to try and power some lights and a grinder. It worked like a champ--even when bearing down on the grinder. I figure I can safely pull a full 30 amps at 110 volts and am going to get a 30 amp plug that services a plug strip.

Next up tonight when it cools down is to add the switching to go from 12v charging mode to weld/accessory mode.