Weldernator... True power!

Just for giggles (and because I was on a welding kick for quite awhile) I decided building a weldernator would be a fun project. I had no idea how to put one together and I didn't want to pay $800 for a kit that I knew I could build for much less. I decided on a plan after doing some research using these sites:

• http://www.geocities.com/Yosemite/2472/obweld.html
• http://www.huv.com/jon/jeep/Welder/on-board-welder.html
• http://home.comcast.net/~t.molnar/Obwelder1.htm
• http://www.madelectrical.com/electri...elcoremy.shtml

Now I just needed to gather parts. I found a new reman'd NAPA 94 amp Delco 12SI on ebay for $20 including shipping. I bought a couple of odd length #2 welding cables from the local welding shop (both of them were spool ends so they gave me a good deal). I had a used stinger laying around from Dad's old Thunderbolt. I bought the ground clamp, quick connects, inline 20Amp fuse, and a switch for the field exciter from a local farm store. I used a gearshift lever and cable from an old mountain bike for a throttle setup. The final price for this project came in at a little under $100.

This was actually an easy afternoon project, most of my time was spent figuring out how to build a mount for the weldernator. The rest of the modifications went pretty fast. It was a little intimidating at first since I have never opened an alternator before... The feeling faded fast once I realized how simple an alternator really was. For the Delco alternator you just have to bypass the voltage regulator and remove the exciter diode shown in this drawing from the second write-up I listed above:I used this diagram for the wiring from the same write-up, but did not add the resistors shown:
The hardest part and most time consuming was planning the placement and fabbing up the weldernator mount. I ended up using some scrap flat bar I had laying around for the mount, bolted the rear pivot support to the engine block and welded the front pivot to the alternator adjusting arm. After a coat of black Rustoleum I bolted it on so now the weldernator will mount right above the existing alternator:
I created a weldernator adjusting arm from old bed frame angle iron which just hooks to the passenger side radiator/grill support bar (that runs back and attaches to the firewall). It is not a permanent setup, I only throw the weldernator on when I need it, otherwise the torsional movement of the engine when wheeling would bend the radiator/grill support rod. It only takes 5 minutes to throw on the jeep when I need to weld with it:The transition from alternator to weldernator modifications were actually the easiest part and took me about an hour to complete. I didn't get any pictures of the inside of the alternator while I had it opened, but you can find them in the above links. I changed out a bolt, added a chunk of plastic to help insulate the positive terminal from the alternator case, and added some quick connects for the welding cables:
I added a switch and an inline 20 amp fuse to power the exciter field of the weldernator seen in the top left portion of the following image. I also attached an electrical outlet to run a drill or grinder:
I rigged up a hand throttle from bike parts, use my dwell meter to dial in the RPM I want, and use a cheap hand held multimeter to check the voltage output:
I bought a new ground clamp, two ~15 foot #2 welding cables, (odd lengths left at the end of the spool at the LWS) and welding quick connects, but used an old stinger I had laying around:
Here is an image of it mounted above the alternator, that angle makes it look like the belts are touching, they really aren't:
I was very surprised at how well I could weld with the weldernator, not that I am a good weldor, but I actually weld better with it then I can with dad's old Miller Thunderbolt. Of course the high frequency DC from the weldernator has some advantages over the AC only Thunderbolt.

Creating a welder out of an alternator was the most enjoyable jeep project I have completed to date. I definitely suggest to anyone thinking about installing an onboard welder to research a DIY setup such as this or the others listed above before you decide to buy a kit. It would be well worth your time no matter what you decide. It was well worth it in my case, for $100 I can say I built an onboard welder that works just as well as the $800 kits, and the $700 I saved will buy a lot of scrap metal and parts for the Jeep and a lot of beer for me.

Now I just need to find some welding projects for my mobile weldernator... :)