Reading a Weld on an Iron Gate

Grind marks tell you almost nothing once a leaf is coated, which is why the joints are worth looking at before the finish goes on. The inspection notes compiled at Pearland Iron Gates, TX Elizabethbaron cover what a sound joint looks like bare, because on iron gates in Pearland the joints are where salt air begins its work.

What a Good Bead Looks Like

Even width, even ripple spacing, and a smooth tie in at both toes where the bead meets the parent metal. A bead that suddenly widens marks a pause, and a pause is where slag can be trapped. Both ends of a run matter as much as the middle, since a crater left unfilled at the stop is a ready made crack.

Undercut and Cold Lap

Undercut is a groove melted into the parent metal alongside the bead, which thins the section exactly where the stress is highest. Cold lap is a bead that has sat on the surface without fusing, and it looks convincing until it is loaded. Undercut is visible with a good light; cold lap usually shows as a bead with a rolled edge and no tie in at all.

Picket to Rail Joints

On a picket panel these are dozens of small welds, and the temptation is to tack rather than weld. A tack holds the picket in place for assembly and is not a joint. Every one is either welded properly or the gate loses stiffness as the tacks fail one at a time over the years.

Dressing and Water

A joint ground flush looks tidy and can hide the fact that a weld was thin to start with. It also removes the small radius that helps a finish sit evenly, so a dressed joint is the first place a coating fails. Dressing is a decision about appearance, and it is worth knowing which joints were treated that way.

Looking at a Finished Gate

Run a hand along the underside of each rail where nobody grinds. Look for a hairline of rust following a joint line, which says the weld is open somewhere along it. Check the hinge mountings and the drop rod guide especially, since those carry concentrated load and see the most cycles.