Tried a new weld prep method on some 3/4 inch plate and it backfired

I was working on a pressure vessel in Tulsa last week and decided to use a 37.5 degree bevel instead of my usual 30, thinking it would give better penetration. The weld puddle went all weird and I ended up with some serious undercut along the root pass. What's the best way to fix undercut on a thick joint without grinding the whole thing out?

4 comments

4 Comments

blair_nguyen2mo ago

Actually in Tulsa last year that exact fix caused a heat-affected zone crack for me.

rowanhernandez1mo ago

Wait you got a heat-affected zone crack from that exact fix? That's wild. I see what @charles122 is saying about the hot stringer bead, but man, that's a scary outcome. Makes you second-guess the whole shortcut.

charles1222mo ago

That 37.5 degree bevel will get you every time. I had to fix something similar by just running a quick, hot stringer bead right over the undercut, then blending it back.

the_piper2mo ago

Reminds me of how @blair_nguyen's Tulsa crack happened, chasing a quick fix. Sometimes the standard way exists for a reason.