Guild D-40: New Bone Nut

Related Topics: Nut | Saddle | Set-Up


1. The Synthetic, Factory Nut on this guitar is worn out. Nuts made from tusq, micarta and other synthetics tend to wear more quickly than frets do. This will cause buzzing and problematic tuning.	2. Finishing Over a Nut is common practice amongst many of the major American guitar manufacturers. The nut is installed prior to final shaping and finishing of the neck. This means that some of this nut's surfaces are covered in lacquer.


3. Scoring the Lacquer with a razor sharp knife will reduce if not eliminate chipping of the surrounding finish when the nut is removed.	4. Sawing the Faceplate with a thin kerf saw will further ensure safe removal of the nut. I'll fill this .011" gap by making the new nut a hair thicker. When all is said and done, the added thickness will not be noticeable.


5. Fracturing the Glue Joint between the nut and the neck with a small block of wood is safe since the finish has been scored.	6. A Safely Extracted Nut negates the need to touch-up the neck's finish and makes preparing the nut seat for the new nut easier and faster.


7. Removing the Old Glue from the end of the fretboard is quick and painless with a razor-sharp chisel. It is imperative that none of the the fretboard be removed.	8. Thickness Sanding the Bone Nut Blank is really fast with the "Luthier's Friend Precision Sanding Station".


9. Preparing the Nut Seat is necessary as the seat must be square, true and free of old glue. Fine grit self-adhesive sanding paper affixed to the bottom of the new nut does a fine job of preparing the nut seat. I am only lightly sanding the neck, not the end of the fretboard.	10. Laying Out the End of the Nut. I've sharpened the end of this mechanical pencil's lead by sanding a shallow bevel into one side of the lead. The resulting chisel shaped pencil lead leaves sharp, precise marks that exactly follow the contour of the fretboard and neck at the end of the nut seat.


11. Shaping the End of the Nut with the disc of the shop's belt sander. Because the layout line on the end of the nut is not square (it never is) I'm slightly tilting the blank on the disc sander's bed so the abrasive disc removes only the material I want it to.	12. Final Shaping of the End of the Nut with 600 grit sandpaper on the shop's dead-flat granite slab will remove all of the disc sander marks. I'm genly rocking the nut as I sand as I fine tune the fit between the end of the nut and the neck/fretboard.


13. Laying out the Height of the Nut. A Pencil ripped in half laying on the frets gives me a good line to sand and file to.	14. Shaping the Top of the Nut using the shop's disc-sander. I've adjusted the sander's bed to 7 degrees which is just about half of this guitar's peghead angle. This is also the average string break angle I'll want for the strings as they lay accross the completed nut. With the disc- sander I'll sand away the excess bone from the top of the nut to just shy of the pencil line on the bass side and just into the line on the treble side. This will give the completed nut proper string protrusion.


15. Contouring the Top of the Nut with fine grit sandpaper both gives the nut a traditional guild nut profile and removes the sanding marks left by the disc-sander.	16. Polishing the Nut with the shop's small buffing wheels gets the bone as smooth and glossy as glass. I load the coarser wheel with jewler's rouge and do the final cleaning and polishing with the clean and compound free, fine wheel.


17. Laying out the Nut for Slotting. I'm using this handy tool sold by Stew Mac. It compensates for the gradual increase in diameter from string to string to ensure an even feel. At this time I'll make any further adjustments to the lay-out to compensate for both the neck's lateral relationship to the bridge as well as any inconsistencies between the notches in the bridge pin holes.	18. Rough Slotting the Nut with a thin nut slotting file ensures accurate slot location. I'll go back and refile each slot with the approp- iate nut slotting file in order to accom- date the strings for final slotting. Note the angle of the slotting file, I file each slot at an angle that is halfway between the plane of the fretboard and the plane of a line from the top of the nut to the hole in each tuning machine post. This ensures full contact between the bottom of the nut slot and the string.


19. Checking the Depth of the Nut Slots. I'm fretting the string between the 2nd and 3rd frets. The distance between the bottom of the string and the top of the first fret will tell me how much material to further remove from the fret slots. The string guage, type of instrument and owner's playing style all combine to inform me how much space to look for between the 1st fret and the bottom of the string during this test.	20. Final Slotting of the Nut. I use a small metal hook to elevate each string above the nut as I fine tune the fret slots. As I make the final few passes with the nut slotting files I lubricate the files with "pro-cut" and apply a minimal amount of downward pressure on the file. This minimizes microscopic file marks in the bottom of the nut slot, which reduces friction between the string and the nut slot fascilitating ease of tuning.


21. A New Bone Nut will outlast this guitar's nickel-silver frets. In order to ensure that the strings both remain in their slots and tune with ease, I slot nuts so the string pro- trusion increases as the diameter of the strings increase.