The ukulele is technically a chordophone classified as a plucked lute. As a subset of the guitar family, it is the Hawaiian adaption of the cavaquinho taken to Hawaii by Portuguese immigrants. Since it has a short neck and nylon strings, a tensioned neck truss is generally not used on soprano or concert ukuleles. Neck bow is generally not a problem; however, it does occur and the repair involves removing the fretboard and steaming the neck.
Items you will need
- Iron with steam
- Boiling water or clothes steamer
- Old t-shirts
- 1-inch scraper with sharp edge
- 3-inch scraper with sharp edge
- Sharp utility knife
- Razor blade
- Several wood clamps
- Short piece of wood
- Short piece of dowel
- Small hammer
- 400-grit sandpaper
- Titebond Liquid Hide Glue
- Safety glasses
- Lightweight work gloves
Cut the bow from around the neck.
Put on safety glasses and gloves. Carefully, score around the fretboard to neck joint with a sharp utility knife to divide the finish. Lay the ukulele on a flat work surface with the neck supported. Wrap the neck in an old t-shirt. Place the steam iron directly onto the covered fretboard at the butt end. Keep the steam going for at least five minutes.
Tap the razor blade lightly into the glue joint at the end of the fretboard to open up a small space for the sharpened scraper. Insert the sharpened scraper and lightly tap with a hammer. Do not lift up. Keep repeating the steam process, moving up the neck with the iron. Let the iron steam each move for about five minutes to soften the glue, then continue to lightly tap on the scraper to separate the fretboard from the neck.
Sand both the neck and fretboard with 400-grit sandpaper, once the fretboard is removed, to remove the remaining glue and wood chips.
Cut the piece of wood to the length of the neck. Put the short piece of dowel as a fulcrum in the center of the piece of wood and pad the wood and dowel with the t-shirt. Lightly clamp the board to the neck until it just begins to tighten. Move the neck back-and-forth in steam from the boiling water or with steam from a clothes steamer. Steam only on the fretboard side of the neck. Steam the neck for at least five minutes.
Continue this steaming process and gently turn the clamps until the neck is straight to just slightly bowed in the other direction. Stop at this point and let the neck rest in the clamps for at least 24 hours.
Remove the clamps. If the neck is flat to just slightly reverse bowed, proceed to reassembly; otherwise, repeat the above process until the neck is straight.
Spread Liquid Hide Glue on both surfaces. Place the fretboard in its original position and attach at least four clamps up the fretboard. Use clamp pads to protect the finished surfaces. Tighten the clamps to apply even pressure up the fretboard. Wipe excess glue off with a damp cloth. Let the glue dry for 24 hours.
Restring, play and enjoy the newly repaired ukulele. Go to Ukulelehut.com and watch Jake Shimabukuro, one of the best ukulele players in the world, perform "While My Guitar Gently Weeps."
Tips & Warnings
- Only try to advance the scraper about 1/4 to 1/2 inch at a time. Let the steam do all the work. If you meet resistance, use more steam.
- Make sure to remove all excess glue before it dries.
- Always wear safety glasses.
- Be extremely careful with sharp tools and steam.
- Do not over-correct the bow in the neck.