I’ve recently started working on a couple (three, actually) new banjos. At the moment, they consist solely of mostly-complete fretboards. I’ll get some more pictures of the fretboards as they develop, but for the moment here are a couple of quick jigs. They’re nothing to write home about, but might spur some thought.
Fretboard slotting jig, aka miter box
I built this miter box several years ago during construction of my first instrument, which was essentially a strum stick (think “long-neck dulcimer with triangular body”). It’s pretty simple, and is constructed of poplar. It was originally adjustable, using some bolts and wing nuts. Turns out I was a bit shortsighted, because the bolts weren’t long enough for the width of a banjo fretboard blank (my blanks were about 2 3/8” wide). So, I hot-glued the two halves down to a scrape of MDF after carefully ensuring they were squared.
Really the only other thing that makes this miter box “special” is that the slot is cut with the same saw that I use to cut the frets. That’s a hardware store dovetail saw, modified to cut slots the width of a fret tang. Basically, I clamped the saw teeth in the vise between two steel plates and screwed it down good and tight to take all the set out of the teeth.
I was thinking of making a more fancy fret slot jig, but would have spent too much time and money on it. As it is, I think this is the last time I cut my own fret slots. Let’s see, Rockler 1/4” thick 3”x24” bocote = ~$15, plus about an hour of my time measuring and re-measuring down to 64ths of an inch, then cutting and sweating… or I could buy a 5/16” thick 3”x20” bocote fingerboard from LMII = $14, plus $9 to get it slotted at my preferred scale length… yeah, wish I’d done the latter!
Binding Laminator Jig
This was inspired by a much more refined jig at Stew Mac. My jig basically consists of a tapered slot in a piece of scrap, with strips of tape as required to adjust the fit. In the wide part of the slot, there’s a nail to keep the two strips of binding apart until they are pushed together in the narrow part of the slot. Basically, you feed two strips of plastic binding into the wide part, and then pull them through from the narrow side. Meanwhile, you hold a brush with acetone between the two strips where the nail holds them apart, so that as you pull them through, they get coated with acetone. The two pieces meet, and bind instantly. Voila. This one certainly isn’t pretty. (I included a couple of strips of black-white laminated binding in the photo for reference.
I needed a shooting board for arbitrarily tapering boards (i.e. for tapering the fretboard edges from the heel end down to the nut end). I found a scrap board about 3’ long with a good straight edge on it, and attached a couple toggle clamps to it. Now I just clamp down the fretboard and run my block or smooth plane along it until I reach the line. Most of the work is in ensuring that I get the fretboard clamped down in the correct orientation.
The jig to the left of the shooting board is my heel angle/radius cutting jig. I’ll have to write about that some other time.