Wooden chairs are a masterpiece of engineering. They support hundreds of pounds, relying on only small braces and legs. But if even one part loosens, the chair can tilt or sag, causing unnatural pressure. The resulting stress can crack or break the leg in a heartbeat. Other problems occur when the chair is abused, slides sideways, tips over or someone uses it to tame a lion. Broken chair legs are usually similar with cracks or splits along grain lines. It’s no big deal to put that chair back on its feet with glue and clamps.
Turn the chair upside down on a worktable. If the leg has separated, place the separated part on the table.
Scrape or cut off any loose splinters, chips or debris from the separated areas on the leg using a chisel. If the leg is not separated, insert a putty knife into any open cracks. Use it to clean out any splinters or debris that might prevent the crack or split from closing up tight.
Pry the crack open with the tip of the putty knife. Inject glue into the crack with the tip of a glue bottle, until the crack is saturated. If the two pieces are separate, apply glue to both contact areas on the two parts.
Fit the broken part back onto the leg by hand. Wrap the area with masking tape to secure the two parts together. Wrap the area with masking tape if the leg is cracked and not separated.
Shoot two, 1-inch pin nails through the leg from both sides of the joint where the leg was repaired. Place clamps on the leg to compress the glued area, placing the clamps at least 1 inch apart.
Drill through the cracked area at a 15 degree downward angle to penetrate all the way through the leg and out the other side using a 3/8-inch drill bit and drill/driver. If the crack is longer than 3 inches, drill two holes, evenly spaced.
Apply glue to the holes to saturate them. Tap 3/8-inch dowels into the holes far enough to penetrate out both sides using a hammer. Allow the glue to dry overnight. Remove the clamps and tape.
Cut the protruding ends of the dowels off flush using a coping saw. Smooth the ends of the dowels using a small file. Color the ends of the dowels using a matching stain marker. Fill nail holes and hairline cracks with a putty crayon.