方形刻度鋼製心軸

The finger sizes engraved right on the steel are a lifesaver when I'm sizing rings at the bench, no more grabbing a separate gauge. It's heavy enough that it doesn't budge while I hammer, and the square shape gives me a flat side to work against.

The engraved finger sizes 1-16 save me from digging out my gauge every time I need to size a ring. Solid steel, so it takes hammering without denting like my old aluminum one did. The square shape also keeps it from rolling off the bench.

I've been forming rings for years and this mandrel doesn't roll off the bench like my old round one. The engraved sizes go up to 16 and stayed crisp after months of hammering. Solid steel, no flex at all under heavy work.