Replacing a Guitar Nut
I always prefer to keep as many of the original parts on a guitar as possible, especially if its vintage. In this case the original nut has had its nut slots filed way too low. In addition it was done using one 3 corner file. I want the slots to be cut for each individual gauge so I decided it is best to replace it. The first step will be to score the finish around the nut and remove it by gently tapping it from the front with a radius block. This will loosen the glue joint so the nut can be removed.
Once removed its time to decide what material to replace it with. I chose a piece of unbleached bone. Bone has always been the go to material for most musicians and is one of my favorites. Before I prep the bone blank I want to remove all the old glue and true up the slot the nut will seat in. I use very sharp chisels and files to do this.
Using a thickness sander the nut blank will be sanded to match the slot and all sanding marks removed with higher grades of sandpaper. A very flat piece of granite or plate glass with sand paper attached works well. After carefully checking the fit the blank will now be sized to the width of the neck.
Once the width of the blank is achieved, the height of the nut needs to be determined. To do this I use a pencil that has been cut in half. The pencil will mark the front edge of the nut showing me how high the frets are. I will use this line as a guide in roughing out the top of the blank.
Next the nut will be glued into the slot. Watered down white glue or hide glue works fine for this. The nut needs to be able to be removed fairly easy for the next person who has to service the guitar so use the glue sparingly. On this nut I will be applying finish to the sides to preserve the original look of the neck. Once dry I will level the finish, blending it into the original finish by sanding and polishing. It makes for a great finishing touch.
The final steps will be cutting the string slots and final buffing of the bone itself. The slots need to be cut for each string using the appropriate gauge. They also need to be cut to the correct height for the players preference. I recommend polishing the bottom of each slot and no more than half the string diameter for the slot depth. This will insure proper tuning stability.