What causes weld porosity in Mig welding and how do I prevent it?
A. Weld porosity in Mig welding can be caused by base metal contamination, filler wire contamination, incorrect weld parameter issues, deficient gas coverage, or even excessive gas coverage causing turbulence and ambient air mixing. Make sure that your base material is clean and ready to weld, and you have no contamination on the filler wire, including rust spots and unapproved lubricants. Check that your weld parameters are set right, including your gas flowrate setting. Finally, make sure that there is no breeze in the welding environment blowing away your gas shield. If so, use a curtain or barrier to block off the weld area.
