The last step in the Pearl Inlay process is cleaning up the excess glue, sanding the inlay smooth and finishing the fretboard.
Start by securing the guitar to the workbench and set in a sturdy neck cradle. Here is a great one you can make and you can get free plans at the Plan Shop – The Ultimate Neck Cradle.
Start to take down the surrounding glue and filler with a double-cut mill file. This will take most of the hills and valleys out. When you get close to the fretboard surface, switch over to a rough grit sandpaper, such as 80 grit and glue it to a sanding surface to get a nice level surface.
When you are just down to the surface of the fretboard, switch over to 120 grit and get all the traces of glue off the fretboard, and also you should remove the 80 grit scratches.
Now inspect the fretboard and look for any gaps, air-bubble or any other imperfections that need to be addressed. If you find some, do not try to sand down to time. Rather, take a little dab of your fine filler and rub it into the hole or gap and then make sure you are above the fretboard surface slightly. Set the fretboard aside for the day. When dry clean-up as above and finish down to the fretboard.
Finishing the Inlays – Polish the Fretboard:
Next take 220 grit and give the fretboard a nice polish. The quality of your inlays are coming out now. Progressively go through 320, 400 and finalize the sanding with 600 grid sandpaper. By now all traces of the scratches of preceding grits should be gone and the inlay should be sparkling. As you use the sandpaper, be sure to use on a sanding surface as the wood surrounding the inlays is a lot softer than the inlays themselves. If you use your fingers as a backer for the sandpaper, you will wind up with bumps and humps in the fretboard.
By now the inlays should be scratch-free and look incredible against the dark wood. Give yourself a good pat on the back.
GLS Tip #1: When you sand the inlays be absolutely sure to wear a good dust mask. Do not inhale any of the fine pearl dust as this will cause lung problems. Once in your lungs you cannot expel it. I prefer to use an N95 Rated Respirator for this.
Finishing the Inlays – Clean the Fret Slots:
Now take your fret saw and carefully cut down through each fret slot to make sure it is clean. Be sure to use the Fret Miter Jig that we have available or at a minimum use a depth stop on the fret saw. Clean the slots out with a shop vacuum prior to fret installation.
The final step is to either dye or put a good oil on the fretboard to bring out the color of the wood and really feature the inlays. If your fretboard is very color consistent, I would skip this stop and just give the fretboard a final finish with the finest steel wool you can get your hands on. A vigorous buffing will really bring out the colors.
Finishing the Inlays – Engraving The Pearl:
If you intend to engrave any of the inlays, now is the time to do that step. That discussion is beyond the scope of this article and will be discussed in a separate piece. Just know that engraving is an art in and of itself and takes a lot of experience to master it. But….you have to start somewhere.