Print-in-Place Hinge

A five-knuckle hinge that comes off the bed already assembled — no pin to fit, no second part. 16mm barrel, 6mm pin, 40mm long leaves, 4mm plates, 62mm overall on the axis. Printed standing on its end with the axis vertical and the leaves 90° apart, which is the whole design: the usual flat-printed hinge lays the axis in the bed plane, and then the barrel's bore is a horizontal hole whose roof droops onto the pin and whose underside is a 90° overhang, with the pin itself printed into mid-air above it. Stood up, every face is a vertical extrusion — the pin is a vertical cylinder, the bore is a vertical cylinder, the leaves are vertical plates — and nothing overhangs at all. Clearances are 0.35mm on the pin's radius and 0.4mm between knuckles up the axis. The 0.4mm is the one gap print-in-place cannot design away: each knuckle's first layer is laid over the top of the one below and tacks to it, so it needs one firm twist to free before it swings. After that the clearance is real and it turns freely. The leaves are 90° apart because at 180° their roots would want the same millimetre of space and print as one lump; in use it swings from nearly shut to nearly flat, and the roots meeting is the stop at each end. Print it with a brim — it stands on two plate edges and it is tall. PETG.

from £10.02example, in PLA