My portable 24v Flux Wire welder

[anickode]

Just thought I'd share the portable Flux Core welder I just put together. It's a flux core wire welder meant to run on 2 car batteries in series. I tore apart my old Harbor Fart 90 amp welder that I haven't touched in years, modified the wire feeder a bit, and mounted it in an old DeWalt laser level case.

The idea is to have a compact, self-contained welder that can be used for emergency repairs anywhere I've got 2 car batteries available, such as off-roading or making repairs in remote locations.

It has a 300 amp car audio fuse inline just in case anything real bad happens. Normal welding should run about half that. I still have to add the battery cables. I'm going to take a pair of heavy jumper cables, cut it in half, use one half for the battery leads, and a piece of the leftover cable and the other 2 clamps for the single cable required to series the two batteries together.

I figured if ReadyWelder can do it with a spool gun, I can do it with a regular wire feeder.

 

[Iplayfarmer]

Have you used it yet? How does it run compared to the stock HF configuration?

 

[anickode]

Haven't tried it yet. Comparing it to the original HF configuration would sort of be an unfair analysis. The HF machine outputs a max of about 83 amps AC welding current. For a general idea of how bad that is, there are NO wire feed welding processes that are intended to use AC current. The original configuration essentially spews metal bird poop. A real wire feed welder should be DCEN for flux core, with a rectifier bridge, inductive arc stabilizer, and a capacitor. The HF rig has nothing but a large transformer with dual-tap input for a "high" and "low" setting.

The modified version uses none of the original power supply parts. It's just the feeder and stinger. 24vdc power is 100% direct from the batteries.

I found another fellow who did almost exactly the same thing, and his results were quite impressive. Still considerable spatter, as with any flux core welding, however the actual welds are not even on the same playing field as the stock HF welder. They look like something that SHOULD come out of a flux core welder.

http://www.jeepforum.com/forum/f37/how-make-trail-mig-flux-core-welder-1096579/

I also just noticed that his sample welds were made using Harbor Fart welding wire... which I've found to be complete and utter garbage compared to just about any other wire.

 

[jake98]

That's a great idea, but we're gonna need live action video. :thumbsup:
Welcome to the forum!

 

[monckywrench]

Cool idea. Some folks have run spoolguns off batteries with success.

 

[anickode]

I have high hopes for it... did some initial tests though, and I've enountered a problem with the feed speed controller that is just baffling me.

In the stock welder, the feed controller draws power from the secondary winding of the transformer. The power is fed into the controller, where it is immediately rectified to DC. You would think then, that feeding it with DC would not be a problem, however when you squeeze the trigger, it starts feeding, but when you release the trigger, it doesn't stop. I hooked the jumper cables to the outputs on the original transformer, and it works fine.

Guess I'm gonna be replacing the speed controller altogether... maybe a simple rheostat would suffice.

 

[RPW]

Feeder controller probably has a SCR (or TRIAC) as part of the circuitry. What happens is when it's turned on (by squeezing the trigger) it will stay on until the next AC cycle reverses the polarity of the transistor. That turns it off. A DC speed controller would be your best bet as you'll get 100% (or near) power from the motor but at the correct speed. A rehistat (sp) will sort of work but as you slow the motor down you'll lose motor force to keep feeding the wire at a slower speed and you'll be disappointed in the results.

Good luck.

 

[vwnotrunning]

Keep us updated on you progress. This would be great for emergeny repairs in the field also. Tractor battery and truck battery!!