Thanks mate,after reading your reply I've had another crack at it today with a smaller cup, and slightly more gas, thus protecting the molten pool , with good results. It made sense when you suggested that the gas was the culprit. Many thanks...I owe you one, Colin.

wondered if anybody can give me advice??? I welded stainless 1.2mm sheet for 1st time today using a miller aerowave hybrid, pure argon, and a 1.6 tip (silver end colour) All looked ok when under way, but when complete, weld bead looked black in colour, and a bit rough, penetration was good. Looks li...