Does anyone know the theory behind gasless mig welding? I know the theory of mig welding is that the weld is enveloped in an inert gas.... but if this is the case how does gasless MIG welding work?

Like solder or arc rods so the arc melts the flux and shields the weld pool, varied opinions on its performance. Not many over enthusiastic ones though.

tried it,thought it was rubbish

I use it nowadays, as I only do occasional welding and it's not worth paying rental for a gas bottle.

It does work - with practice. There is a "gotcha" - the wire is 0.9mm, but MIG torch tips are 0.8mm or 1.0mm (I took an 0.8mm tip and drilled it to 0.9mm successfully). You do get irritating fumes & smoke as well.

David

[Edited on 9/1/05 by David Jenkins]