Then I suggest you practice a little more on the mig. It takes patience but a mig weld can be nice looking and seal perfect if you take the time to practice

Overall nice looking headers though

Very Nice! I would also appreciate a detailed sketch of how you accomplished this.

Travis, just wondering man, could you do this with a lawn-mower engine? I mean, I don't got engines lying around just anywhere, and I sure don't want to take a vehicle apart anytime that I need to get some welding done, so rather than getting an extra vehicle, a lawn mower would be a cheaper way, IF it was feasible.

Travis, Great job!
Would there be any advantage to using a regulated variable voltage supply for the controller? Better stability maybe? IF so then one can be easily built for a fraction of the cost of an off the shelf item. What do you think, waste of time or would it even work?

Travis, I have made several projects like yours in the past. I made a 2 alternator jump box with a old ridding lawnmower. I helped a guy with a welder lie yours and he used a variable speed drive on a 5 hp electric drive. We used screw in rectifiers with pig tails and a SCR controller. Your project is cool, I can just see the smoe coming out of garages all over.

i fogot to mention,
it was a 110v mig without gas, using flux core wire only.
I have a 64' rambler american 330. I got it with a 302 and 3 on the tree. it ran and drove. So naturally i pulled the ford out, and put a 327 in
and i had to make these headers

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fantastic project
can you tap 110 volts of some where when using a gas garden tractor as a power unit?
max

Travis,

Thanks for doing this! I know it takes a long time to do and I do appreciate it. Will be getting together with some friends and we are going to be looking at building one of these.

Another friend's dad has a second alternator in his Jeep setup as a DC stick welder, just in case he breaks something when he is out 4 wheeling. I believe this is similar to your idea. Neat idea using the sliding light dimmer for the foot control.

I have attached a Word document that I made from your posts along with some of the posts where the content adds to the discussion. Hope it helps in creating an all encompassing document in the future.

Now, if someone could just come up with a home made plasma cutter...

Regards,
Rob

Ok well the lesson on voltage dividers was just that .. a lesson.. the voltage dividers are VR1 and VR1 10k Potntiometers.. the o.1 ohm resistors are simply 12" of 14 AWG wire, just a s a means to balance the load on the 2N5885's


the reason we start with 240VAC is becuase we allready have that in the case to run the electric motor.. there is no common in the case to make 120VAC.. i thought about putting a common in there so i could mount a small grinder for grinding the tungsten on the welder itself and later on use it for the high frequency start.. but then it would need its own 4 wire extension cord and plug in, so i said forget it.

for cooling on mine .. when i get the cover built, is just going to be a hole with mesh in it right in front of the alt. the fan on the alt will pull the air in, and you could also put a small fan in front of the transistors to help them out.

I covered this earlier you need at least an 11HP gas engine for a 140 amp alt.

for in shop use just use an electric motor.

That is essentially what the schematic is, minus the regulated part..

originally thats what I was going to use.. then i found out how much they where and how much i dont have.. and built this

lol yes I let the smoke out a couple times learning this, but thats the fun..

I claim no liability.. !!!!!!!DO AT YOUR OWN RISK!!!!!

The problem with changing speed of the motor rather than changing the field coil input, is that it wont have the response time you want.. I use my pedal alot, i think that would be alot harder on the motor as well. Also you wouldn't get the off the line power you need when you strike an arc the alt will be spinning alot slower. Also you will never be able to make the pulser feature later on, as well as any other little feature i can come up with.
Those rectifiers are nice, but they are alot more expensive and alot more work.. when a $25 Transpo part does a great job of rectifying the current.

Flux core will do a much nicer job than hard wire anyday!! it burns deeper and uses less power.. also the gas can't get blown away.. you will get alot less cold lap, and a nicer flatter weld. crank it up and practise practise practise

I actually welded this header up with mig, as i was out of argon at the time... no leaks

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you mean to run grinders and other brush type motors.. (no variable speed drills though)

Yes with full field coil current and the rpms maxed uut, you cun run those off of the welder output. just wire in an electrical box.