Tabletop button

Overview

A button is a short block of hardwood with a rebated tongue at one end. The tongue slides into a groove plowed along the inside face of the apron, and one screw through the body of the block holds the underside of the top. Because the tongue can slide in the groove, the top moves across its width without being restrained. Not bought hardware strictly, but made and fitted in the same way as the metal clips, and used the same way.

Types and sizes

Make buttons in the same species as the table or another hardwood for strength; make the tongue 6 mm (1/4 in) thick and 6 mm (1/4 in) long to fit a router-cut or sawn groove 10 mm (3/8 in) deep. A slotted or oversize hole in the body lets the screw follow the top.

Where it is used

Mission and Arts and Crafts tables, and plain Shaker tables, hold their tops this way: a button costs nothing, uses no metal, and is easily replaced.

Choosing and sizing

One button every 300 to 450 mm (12 to 18 in) along each long apron; a 1.8 m (6 ft) dining table takes about eight. Use hardwood, with the grain running along the length of the button so the tongue does not snap.

Installation

1. Plow a 6 mm (1/4 in) wide, 10 mm (3/8 in) deep groove along the inside of each long apron, with its top edge 6 to 10 mm (1/4 to 3/8 in) below the apron's upper edge.
2. Cut the button with its tongue at one end, the tongue 6 mm (1/4 in) long, so there is spare depth in the groove for the top to move away from the apron.
3. Drill a pilot hole through the body; for movement, ream it to 4 mm (5/32 in) so the screw is not gripping.
4. Slide the tongue into the groove; screw the button to the underside of the top with a short screw (No. 8 x 1-1/4 in, 4.2 x 32 mm) that stops 6 mm (1/4 in) short of the top face.

Wood movement and species

The top moves toward and away from the long aprons, so the tongue slides in and out of the groove: leave spare groove depth of more than the expected movement (several millimetres on a table 900 mm, 36 in, wide). The tongue's grain runs along its length: cross-grain would snap. Keep the tongue clear of finish so it slides freely; a little Paste wax helps.

Common mistakes

• Tongue cut across the grain: it snaps within a year.
• Groove too deep or too close to the apron's top edge.
• Screw tight in the body: the top cannot move and splits.

Related

• Z-clip: bought, slotted equivalent.
• Figure-8 tabletop fastener: simpler metal alternative.