Final Chapter on the Kay cello for little Sister Sailor.
I use this same tool to cast the arc of the fingerboard onto the bridge and mark it for cutting to approximate height for each string. Note that some wood is left after band-sawing, to do the final shaping, and crowning.
Use calipers, dividers, or a good eyeball, just get the string spacing right. File the slots half the diameter of the strings, round them over, graphite them, and I always finish-sand maple bridges. Doesn't matter, looks nice.
Cut a length of spruce soundpost on the bandsaw. I had an old one to go by, so this one was easy. Shape the ends, cut a little at the time, because this little dowel is a friction-fit... only string tension holds it in place. Ideally, I like the top of it positioned proportionally, about the thickness of the bridge foot, and below that about that much, standing perfectly vertically of course. The green X-----> is about where I aim for them to go.
Those little notches in the F-holes by the way... they are how we locate a bridge... they're kinda'-sorta' like timing marks. If the bridge is aligned with these, and standing 90° vertically, the scale is measured from the nut to that witness point. There isn't anything exact about it. There's actually another crazy variable too, by which you tune the string afterlength; the amount of string length behind the bridge-to-tailpiece. This measurement, depending on how big of a fight you want, is supposed to be 1/6 of the scale length. So on a 42" bass, the afterlength should be close to 7". Phooey... maybe on a good bass. (I'm looking at you Casey Vancouver...)
Anyway, since I could adjust the Wittner tailpiece easily, I tweaked this little girl pretty close to that golden ratio, and wound a new set of D'Addario Prelude strings on, slowly bring it to pitch.
She's done. I've been playing it a little while this afternoon. Really sounds nice, plays great too. We'll watch it for a couple weeks and make adjustments as needed. Sister Sailor was supposed to be passing through here headed out West later this month. That'll be the handoff.
Last one is the artsy picture I sent Big Sister.
