Heard a foreman on the North Slope say you should never weld over rust without hitting it with a needle scaler first

Tried it on a tank patch job last week and the weld held way better than the times I just wire-wheeled it, has anyone else noticed a big difference with needle scalers vs grinding?

3 comments

3 Comments

anthonynelson1d agoTop Commenter

Have you tried hitting it with the needle scaler after the wire wheel too? In my experience, that rough surface lets the weld bite in way deeper than just shiny metal. A wire wheel can glaze the surface over, but the scaler leaves it rough enough to hold.

ryan79318h ago

Needle scaler after the wire wheel"? That sounds backward, you're messing with me right?

paul_ramirez1d ago

Yeah that thing about the wire wheel glazing the surface over is real. I've had beads that looked solid but then one good flex and they popped right off because the metal was too polished and the weld basically just sat on top instead of bonding deep. The needle scaler leaves those little craters and rough spots that give the weld something to grab onto. I've started hitting it with the scaler first then wire wheeling just the high spots off and leaving the texture underneath, seems like the best of both worlds. You can really feel the difference when you're running the bead too, it sounds different and the puddle flows way more even.