High feed gets rid of spatter and has improved cleaning action. Welds still a bit drossy. Not bad but some dross on fusion line. I am able to get consistant quality with full 180 bend without failure. Welded alternately and checked lengthwise alignment after each weldup.
NOTE remember to work from centre out to edges on all welds to avoid pinch in at centre.
I line up by striking a line on each plate from the notches put in when they were cut from plate. I keep this as a reference during the butt weld up. Did some test welds on offcuts to figure butt weld requirements. This is 6061T6 stuf so will probably leave some bead on. Test butts in hull stringer, settle on .030 26v 10 feed on inside.