Question about forge welding a simple twist

I was trying to forge weld a basic two bar twist for a gate hinge. The first bar welded fine, but the second one just would not stick no matter how hot I got it. I spent about three hours just on that one joint, cleaning, fluxing, and trying again. Turns out I had missed a tiny bit of mill scale in the twist pattern that kept breaking the weld. Has anyone else had a simple twist fight them that hard?

3 comments

3 Comments

phoenixb342mo ago

Oh man, that mill scale hiding in the twist is the worst. It makes me wonder if the twist pattern itself is trapping scale and flux gunk, almost like a little pocket that's impossible to clean out fully. Maybe a quick soak in some vinegar after the initial clean could help get into those tight spots before you even try to weld. I've had to wire brush the living daylights out of twists for way longer than feels right.

diana_murphy2mo ago

Have you ever cut a finished weld open to check if that burned-out gunk left any porosity or weak spots in the bead? I'm worried it might look okay on the surface but cause problems inside.

the_xena2mo agoMost Upvoted

Nah, vinegar soaks are extra work for no real gain. A good aggressive wire wheel on a grinder gets into those twists just fine if you hit it from all angles. @phoenixb34 is overthinking it. That trapped gunk just burns out when the arc hits it anyway. I've welded plenty of dirty twisted stock and never had a flaw from leftover scale. People stress way too much about perfect prep.