Has anyone discovered why the polarity must be changed on the power feed wires on a wire feed welder when changing from solid wire to fluxed wire?
Electrode positive (DCEP) holds more heat in the torch. Better for thinner materials. Electrode negative (DCEN) puts more heat in the workpiece. Better for thicker materials, and necessary to get the flux to flow. Try it both ways. See how the bead either sits on the metal, or flows out into the metal.
It's appropriate when you have a filler material that produces slag, such as flux core, or outer shield. If you push with flux, you risk including it in the weld. If it slags, it drags.
My dad started me on stick welding. I was never great at it-45 years later I’m a bit better. But dragging the gun with the first wire feed welder I had, was natural. I did it like a stick welder, slight angle backwards, you can see the weld area easy. I’d guess if you can’t tell where to weld, you may have the gun at too severe at an angle. Nothing has come apart yet, so I’ll continue on.
What I have found is with flux wire polarity, running solid wire won't even strike an arc. Doesn't make sense to me since it is just electrical potential between two electrodes. Haven't made the mistake the other direction recently but as I recall the same thing happens. Won't even strike an arc.
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