I'm not a pro welder nor much of a mig operator but I do do TIG I noticed that you weld left to right in the video, would it work better if you welded right to left? Which is the way I was taught to MIG weld. ie the ripples forming on the cold side not the front side where it would be recieving the ...

What wall thickness is the tubing? What amps have you been welding at so far? for 1/16" thick I'd start at about 25-30 amps for a butt joint. very little gap. pure Argon. lanthaniated electrode sharpened to a point. regrind electrode if you have a tip strike. and check out the clip on how to ta...

What is the thickness and joint preparation, amps etc that you have been using?

I'd increase the angle of the vee shown in diagram B to about 45 degrees and leave a small amount at the tip say 2mm and fill that in in 2 or 3 passes then do your fillet on the inside, or do 1 run on outside then do inside fillet then finish the outside. You sould be able do a reasonable job withou...