May be looking for the unobtainable....

[njw]

First post here, although I've lurked for a while, so please be gentle!

I'm after a constant voltage power supply to go with a wire feeder I already own to make a highly portable MIG welder. The complication is that I'd like to be able to run it off as small a generator as possible (ideally about 3.5kVA).

For practical purposes, therefore, I need an inverter, not something transformer based. It seems that all of the small inverters are aimed at MMA welding and I haven't found anything which is small, fairly low power and constant voltage.

Within reason, cost is a secondary factor and I have considered buying a small inverter MIG with an integral wire feeder and either using that instead of the wire feeder I already have, or possibly even chopping the power supply out of it and putting it into a new case. However, I haven't been able to find a small MIG welder which I am sure will run off a small generator.

What I'm looking for may not exist, but if it does, I reckon someone here will know about it.

Looking forward to your comment, and thanks for any help!

Nick.

 

[wheresmejumper]

I think youll struggle to find anything thatll work off 3.5kva

 

[penfold]

Broadly speaking you need double that power of generator to run even a small welder with anything approaching reliability; even if nothing blows up the genny will bog every time you pull the trigger and it will send all your settings to cock.

I suppose it could be possible to fit a separate wire feeder to a integrated MIG, but why would you want to? What are you gaining?

 

[njw]

Well, I have a friend who has a very small MMA inverter which runs nicely off his 3.5kVA generator, but of course that's constant current, not constant voltage. There isn't any advantage in fitting a wire feader to an integrated MIG (except possibly so you can use a Eurotorch - most small integrated MIGs do not have a detachable torch) but I already have a wire feed unit so I was hoping to find a small constant voltage PSU to go with it. Portability is my main objective - I want something I can fit in the back of a LandRover and run off the (hydraulic) PTO driven generator I already own.

 

[BrokenBiker]

surely you still need the main welder too though. All the wire feeders i have seen are just motor units with a speed control, the voltage settings are set on the actual welder. Mind you i have only used one mig with a seperate wire feeder unit

 

[njw]

The wire feeder was an e-bay purchase. I have another complete MIG welder but it's a 240A 3 phase unit and well outside any reasonable definition of 'portable'!