Pivot hinge

Overview

A pivot hinge replaces the side-hinge with two plates and a pin, one set at the top and one at the bottom of the door. The door turns on the pin, which sits in a socket in the carcass top or bottom (or in a plate fixed there). Nothing shows on the side of the door, and the door can overlay the face or sit flush. It is used for flush cabinet doors, bi-fold closet panels, display cases and doors where a visible leaf would ruin the line.

Types and sizes

• Surface-mount plates screw to the door edge and to the carcass; mortised versions sit flush.
• Bored versions have a pin on the door that drops into a drilled hole in the carcass.
• Pin diameter about 6 to 10 mm (1/4 to 3/8 in) is typical.
• Some types are self-closing with a spring in the pin.
• Not to be confused with the 35 mm cup hinge; see European concealed hinge.

Where it is used

Not named in the library's style guides. It is common in flush and frameless contemporary casework and in doors that must swing clear of a full-width overlay.

Choosing and sizing

Check the door thickness against the maker's range. The carcass top and bottom must be thick enough to take the socket, at least 18 mm (3/4 in). Mind the swing: a door that pivots on its edge needs the opening's clearance on the hinge side.

Installation

1. Mark the pivot point: usually 10 to 20 mm (3/8 to 3/4 in) in from the hinge edge on the door's thickness centre line.
2. Bore or mortise the door's top and bottom edges for the pin plates.
3. Bore or mortise matching positions in the carcass top and bottom so the pins align exactly vertical.
4. Fit the lower pivot first, drop the door onto it, then fit the top one.
5. Check swing and gap; adjust the plates, not the pins.

Wood movement and species

The pin bearing area is in the end-grain edge, so use a hardwood or a face-grain insert in softwood. The door's width change shows as a varying gap on the free edge, since the pivot line is fixed. Allow a clearance of 1.5 to 2 mm (1/16 in) at the free edge in a solid-wood door.

Common mistakes

• Pivots out of plumb: the door swings itself shut or open. Use a plumb line or a template.
• Bottom pivot sinks into soft end grain: use a bearing plate.
• Door binds against the carcass at the pivot edge.

Related

• Knife hinge: another hinge that disappears into the door edge.
• Butt hinge: the visible alternative.
• Magnetic catch: to hold the door shut.