Got a welder to show me his root pass trick on a site in Gary last week

Watched him run a downhill on 6-inch schedule 80 and he kept his arc so tight I couldn't see the puddle move, now I'm wondering how long I've been leaving too much gap on my own fits.

2 comments

2 Comments

sethhernandez19d ago

Spent a whole shift on a 10-inch root pass with a guy who ran the tightest arc I ever saw, and I realized my problem was I was chasing the puddle instead of letting the rod do the work. Once I stopped cranking my hood up to peek and just trusted the angle, my gaps started looking fine.

verawhite19d ago

Been thinking about this... everybody focuses on the gap but nobody talks about how the backing ring thickness changes the game. On schedule 80 in Gary those pipes are heavy walled and that extra metal makes a difference in how the puddle behaves. I've seen guys run tight arcs on heavy wall just to keep the heat in because the metal soaks it up and leaves you chasing cold starts if you're not careful. Maybe that welder was compensating for the pipe mass more than the gap itself. Plus on a downhill root the rod angle matters way more than the spacing in my experience... too much lift and you're fighting gravity plus losing control. Might be worth checking how your base metal thickness compares to what he was running before you change your setup.