How to Break a Wood Glue Joint

Using a Heat Gun

Heat the area around the joint with a heat gun. Hold the heat gun six inches (15.24 cm) away from the joint and continue to move the gun around. Do not leave the heat gun in one area or you may end up burning your woodwork. Continue to move the heat gun over the joint and soften the glue holding the joint together. You can purchase a heat gun online or at a hardware store. If you don’t have a heat gun, you can use a hairdryer on the high setting.

Work a flat tool into the joint. Once the glue is hot, you should be able to penetrate into the joint with a sharp tool like a knife or metal wedge. Carefully work the tool into the glue while continuing to move the heat gun over the joint. Continue to wiggle the tool back and forth until you cut through all of the glue adhesive. Clean built-up glue off your flat tool with a damp rag as you work.

Pull the joint apart. Once you cut the adhesive with the knife, the two pieces of wood should loosen. Use your hands and carefully pull the joint apart. If desired, wipe the glue from the wood with a damp rag while it's still hot. Peter Korn Peter Korn, Woodworker and Educator When trying to break a wood glue joint, first understand the glue type and wood grain orientation. Carefully warm the adhesive to soften it, then employ a thin blade, patiently working it along the joint line. Forcing the joint risks wood damage. If the joint resists moderate effort, consider cutting through it and planning a repair instead of potentially ruining the piece. Patience and care are essential.

Using Denatured Alcohol

Inject denatured alcohol into the wood joint. Suck up some of the alcohol with a syringe or eyedropper and place the end of the dropper or syringe against the joint. Press down on the top of the syringe to inject the alcohol into the joint. Repeat this method until the entirety of the wood joint is saturated. You can purchase denatured alcohol online or at a hardware store. Work in a well-ventilated area when working with denatured alcohol. Denatured alcohol will loosen up and dissolve the glue.

Wiggle a knife into the joint after five minutes. Let the alcohol sit on the joint for five minutes, then wedge a knife in between the two pieces of wood. Work the tool on the edge of the joint until you can start penetrating into the joint. As you work the knife, the wood joint should start to separate. As the alcohol sits on the glue in the joint, it will start to break it down.

Spray more alcohol in the joint as it opens. Keep working the joint open with your knife while spraying more alcohol over the glue that's holding the joint together. As you work the knife and continue getting the joint wet, you'll start to loosen up the joint.

Pry the joint open. Scrape away as much adhesive as you can. As the joint loosens, use your hands to pull the joint apart.

Prying the Wood Apart

Use this method if you don't mind destroying the woodwork. You should only use this method if you need to break down furniture or wood and don't plan on using the wood afterward. Manually prying the wood apart can chip or crack the wood surrounding the joint.

Hammer the flat end of a crowbar, flat-bar, or chisel in between the joint. Position the flat end of a crowbar or flat-bar in between the joint. Hit the opposite end of the bar to drive it in deep between the joint. Continue to pound the crowbar into the joint until it's at least three to four inches (7.62 to 10.16 cm) into the joint itself.

Pull down on the opposite end of the crowbar. Apply a decent amount of pressure on the other end of the crowbar to pry the joint apart. This will break apart your wooden joint.