HOW TO USE THE Fretboard Radius Jig
The jig comes completely assembled. You will need to make sure you have all the parts that should be in the box. You should have 8 end pieces(2-12" Radius, 2-14" Radius, 2-16" Radius, and 2-20" Radius). 1 Fretboard Rest, 2 black knobs, 1 base, and 4 screws(already installed in the base of the jig)
Start by choosing what radius you want your fretboard to be. Select the 2 end pieces and rub them against the end of the fret board rest to loosen the groove. You should always do your first test on a practice fretboard. You will need to determine how much deflection is caused by the sander and take precautions later in the test. Attach the 2 end pieces.
Place the 2 ends in the dado's on the base and then put the knobs back on the threaded rod, but do not tighten all the way.
Flip the jig over and make sure the ends are flush with the sides of the base. Attach all 4 screws. You may need to adjust the barrell nuts by turning them to line up the holes so the screws go in easily. Make sure it is tightened very snug and there are no gaps between the 2 ends and the bottom of the dado.
Draw a center line on your fretboard rest. Drill holes in the waste area of the fretboard. Or you can use double stick tape to attach the fretboard. If you do use double stick tape, make sure it is thin, and that you place it in the middle of the fretboard, since this area is where the deflection occurs. The tape will help raise this area. Draw a center line on your fretboard. Place the fretboard on the jig and line up the center line of the fretboard with the center line of the fretboard rest. Screw the fretboard down and make sure the screws are countersunk so the screw heads are below the top of the fretboard. To make this job easier in the future, you can create a template out of poster board that marks the exact location of the screw holes. So you can place the template on another fretboard and locate the exact screw holes every time.
Make sure the fretboard and the base are in the middle and lined up with the center line on the jig. Go ahead and make the first pass through the thickness sander. The drum should be in the most open position available, and as you pass the jig through, lower the drum slowly. Just as it contacts the fretboard stop lowering the drum. Send the jig through one more time to get an even pass on the fretboard.
Loosen the 2 knobs and move the fretboard rest over evenly by about 1/4". Be sure to line up the reference marks and make sure both ends are symmetrical at each end. Always start from the middle and work towards the edge. This allows you to remove as little material as possible while not affecting the deflection too much.
Tighten the knobs then place some white pencil marks on the fretboard so you can check your progress with each pass. Then go ahead and send the jig through the thickness sander. Continue moving the fretboard rest in one direction either right or left, then go back to the center and go the opposite direction.
Place your radius gauge on your fretboard to check for radius, and then admire your work!