Paloma, I too am trying to learn to O/A weld aluminum. More heat and move faster has been the key for me. Our tip sizes in New Zealand are quite different from the US sizes, but I started off with a #6 thinking that the stuff would immediately fall on my jandals and gradually worked up to a #12. 12 was bit quick for my skill level, but #10 seemed fairly controllable. I didn't seem to have much trouble tacking without filler - torch agitation seemed to be the key (much the same I think as mashing the peddle when using tig) to create fusion, but then the welds were very difficult with lower heat. I was trying to use slivers sheared from the edge of the sheet as filler rod and this hampered me somewhat due to the rectangular section and resulting high filler deposition per dab. I'm about to try some real panels with some 16swg 4043 filler on the 5005 16swg sheet. Apparently this filler rod is more forgiving than the 5005 parent metal. As with all skills, time in the seat is probably the key
Which particular Ducati affliction do you have?
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