I am trying to figure out how to do the root pass on a 2G plate test with backing bar, 7018, 1/4" gap, double bevel. I am using 1/8" 7018 at 130 amps, around 20 - 25 degree bevel. I usually do a 2 pass root Where I run my first bead on the bottom bevel and backing strap tying into both while leaving a gap on the top bevel and backing strap to penetrate the backing strap and top bevel. The problem is I can get a perfect first pass but the bevel angle doesn't allow me to get in that gap I leave to run my second pass. When I do it I get a bunch of trapped slag and incomplete fusion, the rod sputters because it has to long of a arc length. Is there a better way to run this root pass in 1 pass that will let me tie into the bottom bevel, backing strap, and top bevel? Once I get pass the root I am golden all the way to the cap, I just want a bullet proof way to run the root. The 2 pass method seems to work real good on 3G and 4G as I have passed both of these on inch thick.
Right now I am practicing on 3/8" plate till I get the root solid, the west test I am prepping for will be 1" thick.
Right now I am practicing on 3/8" plate till I get the root solid, the west test I am prepping for will be 1" thick.