So I'm a carpenter, not a steelworker. I bought this from Hope so I could glue it to the metal ceiling track when framing to line up the stud and I didn't have to hold it. Unfortunately the magnet/weight ratio is not suitable for this application. But it is very convenient to just stick it on the nearest hairpin and leave it there while moving the stairs. I've had it slip off my cleats twice, but the cleats were a bit greasy. The magnet comes in very handy when making a cut on a hairpin with a razor. You can hit the square and it will stay right on the mark as long as you grab or bump the knife. The dimple lines are fantastic and I found them very accurate with pencils large and small.