The technique I know is
- set-up your MIG-set by running bead-on-plate stringers in the flat position on 3mm / 1/8th-inch sheet/plate (looking for nice penetration of heat on the underside - indicating you are on those about
- weave your big v-up fillet on this condition - likely using "the Christmas-tree weave" What's the recommended technique? Didn't get time to practice - had a job and got a satisfactory result
- but still thinking.
What is the exact setting you are looking for, with the MIG machines V-tap and WFS? I know of SMAW weaved v-up - say with 6013. You always look at the side you are NOT arcing at, looking for it to solidify - at which point you dodge back. You set the Amps so you get the right freezing rate so the weave which results is something just under a second dwell per side. Get it right and you also get very nice "slag shedding" - the slag seems to draw away "like a curtain" just as the weldpool is about to solidify, clearing the way for the return of the arc, for a perfect progression. Obviously, there's no slag with MIG. What is the MIG v-up technique which I need to go onwards-and-upwards?
Rich S