Oblong Punch

An oblong punch works exactly like a drive punch — a hollow, sharpened tip struck with a mallet to cut through leather — but instead of a round profile, its tip is shaped as an elongated rectangle with rounded ends. That shape is exactly what a belt buckle's tongue or a strap's fitting needs to pass through, which is the tool's main job: cutting the buckle slot on a belt, or the strap slots on a bag, collar, or harness piece.

Oblong punches are also sold as "slot punches" or "bag punches" depending on the supplier, and the terms mostly overlap — a slightly larger, longer oblong punch is what's typically used to cut the wider slots needed for a shoulder strap to pass through a bag panel.

How to use it

1. Mark the exact center and orientation of the slot — oblong punches only cut cleanly if aligned correctly, since the shape isn't symmetrical the way a round hole is.
2. Work on a cutting board or poundo board, never directly on a hard bench surface.
3. Set the punch upright over the mark and strike firmly and squarely with a mallet or maul — a rawhide or poly head is preferred over a steel hammer, which can damage the punch's flat striking end.
4. Clear the punched-out slug from the punch before making the next cut if it doesn't come free on its own.

Care

Store the punch somewhere dry to avoid rust on the cutting edge, and always strike it with a non-metal mallet to protect both the tool's striking face and its cutting edge from deforming. Because the cutting profile is a shaped rectangle rather than a simple curve, sharpening it evenly by hand is more difficult than a round punch — many crafters replace rather than resharpen these once they dull.