What an amazing resource the Internet
is! I found a web page with a fret calculator at: http://www.buildyourguitar.com/resources/fretcalc/jscrptclc.htmWhat an amazing resource the Internet
is! I found a web page with a fret calculator at: http://www.buildyourguitar.com/resources/fretcalc/jscrptclc.htm
Type in your desired scale length. and it calculates the distance of each fret from the nut in inches or millimeters. I had originally intended to go with a 14 7/8" scale (Martin's concert uke scale) but I was a little off when I built up my neck and had to use 14 1/2". You may or may not know that the distance from the nut to the 12th fret is half of the scale length - in this case, 7 1/4". The distance from the 12th fret to the saddle is half the scale length plus a little more. This "little more" varies for each string, depending on its diameter and other factors. This variable is called "compensation." For an excellent article on the subject, go to David "Kawika" Hurd's web site at http://www.ukuleles.com/Technology/compensate.html
I printed out the numbers that the calculator gave me and I then opened up a document in QuarkXpress (a page-layout program used by desktop publishers). I used the line tool and created my starting point, the nut. Using the "Step and Repeat" function, I created lines representing each fret using the figures from the fret calculator. I printed this out and Viola! - I had a fret template. I cut this out and attached it to the rosewood fingerboard blank that I had previously thinned to 1/8" with the Safe-T-Planer.
Because I was unable to find a saw with the correct .023 kerf
(blade thickness) at any of the local harware or woodworking outlets
(including WoodCraft or Paxton's
)
I went ahead and ordered a fret saw from Stewart MacDonald lutherie
supply. It cost $19.95, and makes beautiful cuts. I also bought
some herringbone purfling for my soundhole rosette, mandolin fretwire,
a bone saddle and nut, also for a mandolin, and some mother of
pearl position markers for the fingerboard. Neither Stew-Mac nor
Luthier's Mercantile sell any supplies specifically for ukuleles,
so one must improvise.
I dug out my dad's old miter box, a nice mahogony job from the '60's, and added thin pices of wood to the top of the 90-degree slots in order to give me a 1/16" depth-of-cut. This accomplished, I was ready to begin. For some reason, I was quite nervous about this operation. It seemed such a precise undertaking and, of course, any mistake would result in less-than-perfect intonation. I decided that a hombrewed Scottish Ale was called for (I've been a hombrewer for about 10 years) and, taking a couple of swigs, I began. I lined up the miter slot with the lines on my template, made sure that the fingerboard was flush with the side of the box and sawed away until the thicker top part of the saw grounded out against my stops. I reversed the fingerboard in the box and cut each slot from the other direction to make sure that the slot was a consistant depth on each side. It took about 30 minutes to cut 19 slots, and when I finished I was rewarded with clean, uniform fret slots, perfectly aligned. I had done it!
Now I had to taper the fingerboard. It is necessary cut the slots before the taper because the sides of the board must be parallel to get the slots at the proper 90 degree angle.
I built another jig for my table saw to cut the taper. It is a very simple, but quite effective tool.
Using a 1x12"
pine board as the base of my jig, I cut a "rail" of
wood that fit in the miter slot of my saw table and nailed it
to the underside of the board. I then ran the board through the
saw so that it the edge would be parellel and flush with the blade.
I screwed two cleats to the board to hold the fingerboard tightly
in the jig. "Stopper" clamps, available at WoodCraft
and in tool catalogs, would be a much easier and more elegant
way to hold the fingerboard in the jig, but I didn't want to spend
the money right then.
I laid out the outline of my taper on the fingerboard and aligned the pencil line with the edge of the jig. You simply run the fingerboard through the saw, then reverse it in the jig and cut the other side. Again, a good, sharp blade in the saw makes a big difference.
I'll cut the fingerboard to length, inlay my position dots and install and dress the frets later in the build.
