Here are the bridge-blocks, all glued into place. Took parts of three days, two more blocks every half hour...
How it was done. As mentioned, I first drilled pilot holes in the oak moldings, using the #63 "wire guage" abrasive drill bit (so I don't know if final diam would be same with a #63 regular bit, I'm guessing not).
Coated with 3-4 coats of polyurethane, top and back surfaces only (not bottom)...
Bridge pins hammered into place. Brass-plated steel "escutcheon pins", #18 x 3/4".
Dicing 'em up...
Now, crucially, right after dicing them, I painted the side faces with Titebond; I hope this prevents gradual splitting.
I rigged up two different clamping systems, ultimately, which made the work go at a reasonable pace. Each block I allowed to dry 1/2 hour before removing the clamp. This is what the Titebond II label suggests, and I found it to be about right, conservatively, under these pretty-good drying conditions. I *probably* could have taken the clamps off at 10 minutes. So 30 was perfect.
One clamp I did with bent wire, a spring. One arm of the wire presses down on the middle of the curve of the molding, then it bends around and the other arm of wire presses forward against the back sides of the nails, thus giving a torque as well as downward pressure.
These molding pieces are particularly hard to clamp down, because the nails form the most-plausible attachment point on the slippery (polyu-finished) curved slopes, but the axis of the nails is *almost* at the tipping point: not only are the nails close to the edge of the quarter-round, but even worse, the molding has a small bevel on its corner edge, presumably to help it fit flush when used in its intended purpose. But that bevel means that pressing down on the nails, or in their vicinity, is very prone to make the darn thing flip out from under you. Hence the need for slight torque.
The other clamp used a weight, pressing a wire guided by the straw. The straw snugly "held onto" the two nails, and kept the downbearing force from the steel wire corralled close to the top of the molding.
Neither clamping system was optimal, both required quite a bit of delicate fussing to get just the right downward pressure, slight forward torque, but no sideways or twisting torques, and no translational pressure, at each new block position. Some of my positioning is a little ragged, I think a couple creeped slightly due to the "bad" forces I mentioned, but hopefully it's close enough for Baroque n Roll.
The bigger issue, and you can just see it in the top of the two photos above, is that, well in short, I screwed up! As I was marking out the bridge positions, I realized that I didn't have room for the lowest, longest note, E2. Oops! Heh heh. This is the "fog of war", when it comes to designing and prototyping. Yes, I had originally ensured that there would be space, but many of the exact proportions have been fluid as I worked out the exact bracing of the frame, etc.; and crucially, I had not double-checked my plans, given myself a "sanity check", in a while. It would have helped if I had constructed the big "ruler" with all the string positions marked, long ago. The problem would have been obvious, as I moved the ruler around to estimate where strings would go. Lacking the ruler, I measured key note positions individually, but clearly not that longest one! (Also a factor might be my little pocket tape measure, which can only do about 1 meter.)
Anyway, once I realized that I had experienced some "measurement slip", I had to make a decision. With the wrestplank not glued in yet, and much of "that end" of the instrument still very much unfinished and undefined, I could have "easily" moved the wrestplank back (well, forward); I also considered doing this to make the "gap" wider, in designing the action. But the widening of the gap was the problem, here. The amount of translation forward to actually fit the correct E2 length, would have made the distance the high notes would have to span, too wide. I don't want to actually lose notes, from top or bottom. So, the way to keep the E2 is to do what every other stringed keyboard instrument does, allow foreshortening in the bass. For me, it will just be the one note. I could widen the gap some, and have slightly less foreshortening on the E2; alternatively, I could begin the foreshortening a few notes above, and gradually "blend" the tone down to the E2. But I chose neither of these mitigating strategies. If the E2 can't be "perfect", then I won't disturb the rest of the design to make it only-halfway. There may be a rather-noticeable contrast in tone colour, between this bottom note and all the others. If so, that'll be an interesting experiment in its own right. But I'll still probably build future instruments with the bottom note fitting better!
Rather than taking drastic actions or simply starting over, I am choosing to embrace this mistake, as a learning experience for myself and hopefully for those who read this. Some of the Native American traditional artists insert intentional "mistake beads" into their work, as a sign to God that they are humble and know they are not perfect: not trying to upstage God. I like the idea of conversing with God through artwork, but I have never thought it necessary to intentionally put any "mistake beads" into my work: they happen often enough naturally. I'm not pulling any punches, I'm trying to do it as well as I can, and any mistakes are "the real McCoy"; if you confuse me with God then you'd better have your vision checked! So I proudly preserve this big little f-up, right there at the peak of my instrument, always reminding me to measure early, measure often.
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