What is Back Gouging?
Back gouging is the removal of weld and base metal by arc gouging or grinding from the other side of a partially welded joint to assure complete fusion and penetration upon subsequent welding from that side. Aluminum miller blades can be used for milling, cleaning up and grooving, and cutting out welding tacks. These blades are made to industry standards and can be sharpened many times.
Welding aluminum without making a back gouge before welding the backside of the material can cause you problems. The lack of a back gouge can cause voids and overall lack of material..