Have you ever seen a bone nut with a chunk missing or a chip in it? This is a fairly common situation. When this occurs, players often choose to replace the nut entirely, and there is nothing wrong with this. In fact, it is the best scenario. However, sometimes clients want a quick inexpensive fix. There are a number of different ways that this can be fixed. There are repair techs that even go as far as to use a method of dental bonding, a procedure in which a tooth-colored resin material (a durable plastic material) is applied and hardened with a special light, which ultimately “bonds” the material to the tooth to restore or improve a person’s smile. Dentists use this method to repair cracks and chips in teeth, so it is a process that is easily modified to fix a polished piece of bone. It is a really cool process and it works brilliantly, however it is not necessary.
Now, its time to share a little trade secret with all of you (shh… don’t tell). If you mix baking soda with super glue, it looks remarkably like bone! Super glue’s chemical name is cyanoacrylate (abbreviated CA), and it is actually a catalyzing acrylic. Super glue is a staple in the modern repair shop. It can be used for multiple purposes – I often even use it to hold cuts closed when I don’t have a band-aid. In the event that there is a chip in a bone nut, the chip can be filled with baking soda and then cyanoacrylate can be applied to harden the filling. This process can be repeated if necessary to build up the filling in the chip, but might not have to be. Then it would need to be filed and shaped to match the nut that it was formed to. After this, use sandpaper to eliminate the file marks, and proceed to a finer grit of paper to take out the rougher grit paper’s marks. I like to clean it up and use a car polish to shine the entire nut afterward (my personal preference is called “show car glaze,” but any polish will work). This process can also be used to fix chips in a bone saddle, or even to fill in a string’s nut slot in the event that it is too low creating mechanical buzzing because the string is resting on top of the first fret. After the slot is filled, it must be cut to the proper depth again with a fret file.
See! Super glue truly is super!
By Dave Bolla
Grosse Pointe Music Academy Staff/ Certified Luthier