Forging an Iron Strap Hinge — The Joint That Opens Every Door

Before the iron hinge, doors were hung on leather straps or wooden pivots that wore out in months. The iron strap hinge — two flat straps joined by a pin through rolled eyes — solved this problem permanently. A well-made iron hinge lasts centuries, as demonstrated by medieval church doors still swinging on their original hinges after 800 years.

A strap hinge is forged from two flat iron bars. Each bar has one end curled into a tube (the eye) around a mandrel. A pin passes through both eyes to create the pivot. One strap is nailed to the door and the other to the frame. The hinge works because the eyes wrap around the pin with just enough clearance to rotate freely but not wobble.

This blueprint teaches three essential smithing operations: drawing flat bar, scrolling (curling metal around a mandrel), and punching nail holes. These same operations appear in gates, latches, brackets, and every other piece of architectural ironwork.