Mig Welding Aluminum Problem – Black Powder Residue
I had a struggle recently trying to solve a mig welding aluminum problem. I do a lot of aluminum mig welding, primarily with 4043 wire and always wonder, what is that black powdery residue on the edges of the weld? Was it soot? If so, where would the carbon be coming from? Was the argon sucking in carbon dioxide from the atmosphere (venturi principle) and contaminating the weld?
I do a lot of aluminum sculptures and am always looking for a better clear coating for aluminum. I am a big fan of SculptNouveau.com and have bought a lot of patina chemicals, coating, dyes, etc. from them over the years. Debbie Young usually drop in a free sample of something new to try. Ron Young’s has numerous videos for sale and on You-Tube that are quite excellent.