But anyway, to make a short story long. I feel like Gromit, but in extreme slow motion. One segment per day, at best, given the 24-hr minimum drying time of this Titebond II glue. And they don't lie, it's at least that; especially when I seal the bottom of the joints with Duck Tape, so that I can do the gluing without laying out a huge tarp under everything (and probably walking through it): this limits airflow, and the portions of glue bead in contact with the tape will still be wet at least 12 hours later, when most of the other glue has at least dried to a pliable, rubbery state, or beyond. It'd probably take 48 hours or more to fully dry, if I didn't "rip the bandaids off" and accelerate the drying. I doubt that it is good to have such a differential in drying rates;
maybe I could find a way to mask with paper or something, which would have some air permeability and/or glue absorption.
Here, I've just laid the soundboard on top, to see how it's gonna fit.
Shorter "bentside" piece: one more to go, the cheek piece.
Fitting each successive piece (other than, of course, the original two long pieces, which didn't join to anything initially) has been a repeat of the painstaking iterative grind-to-fit operation. This lets me know that there isn't a square angle or straight surface anywhere on this rig! But at least it will all look like it fits together. Fitting the lid, when that time comes, may be something of an art: I highly doubt that the top edges of all the case lumber will be truly co-planar, though I hope they are close.
As I finish up this step of adding the sides, next steps include: pre-drilling and fitting the wrestplank, pre-drilling and fitting the nut and bridge pieces (the nut in my design is a single strip of oak molding, but the bridges are short segments of molding, all diced up, one piece for each pair of strings at a given pitch); and then I'll be ready to start the finishing process on the case. As in, spraying it with polyurethane finish -- the overall project won't be anywhere near "finished".
I have decided to spray all exposed surfaces with polyurethane, both inside and outside of the soundbox. So this presents something of a challenge, as to masking and ordering of operations. (And I say "spray" because it's a good quick verb that is less ambiguous than "finish", but in fact I'm not positive, I might use a brush for at least some of it.) I'll have to spray the inside of the soundbox, and the back side of the soundboard, with both areas properly masked where they will glue together. Then glue the soundboard in place: I think I can do that process before the first polyurethane is fully dry, i.e., perhaps after 24 hours. Then, the outside surfaces can be sprayed, again maybe 24 hours after gluing the soundboard; however, I may have to position the case different ways to hit all the surfaces, so more than one session may be required. Anyway, after 3-5 days of that, the whole thing will then need to sit and thoroughly dry: which may take another solid week, judging by my prior experiences with this type of finish (under conditions of better airflow).
None of this can be done in my apartment! Nor is there space outside. The outdoor-air-exposed basement hallway where I did much paint and finish drying for projects like the pedalboard, does not have enough space to fit this pandalon (I checked), without being seriously in the way of the other residents. This is a real issue, for this "cottage industry" concept. I use a minimum of harsh chemicals, where possible, but here there is no way to escape a process which is simply not compatible with indoor living. My solution will be to borrow a friend's garage space. Others undertaking a project like this will have to solve the matter for themselves; I considered ways to do it "on the premises", like constructing a special-purpose "tent" or shelter, so I could store the instrument in the backyard for the days of drying (or I also considered the roof...). But, between humidity and vandalism, I'm happier having it on my friend's property, assuming that the plan works out. This will be a first chance to assess how much of a pain in the ass it is to move this instrument, as well!
Oh yes, and about the soundboard. Original plan was glue-n-screw. Then I got all fancy with no screws on the case sides, so I wondered if the soundboard would look bad in comparison. The usual approach is the "go deck", which I don't have... but maybe I should... But anyway, I think I have a good solution here, and critically, given the two-part finishing process I outlined, it's one I can execute up at my friend's house, in between polyurethane coats. (Of course, my "portable go-deck" would also fit that bill, but it has yet to be built -- or even fully designed! -- yet.) Glue-n-nail. I think I can find some nice-looking brads, brass or copper looking, and space them quite a bit more closely than I was going to do with the screws, and it'll look not-bad. This will also give me a design-coherent way to delineate the positions of all the braces, which I want to do, so that I can analyze their effect on particular notes and such. I also plan to put some decoration around the sound-holes, astrological symbols and such; I will make these in metallic finish, to match, or at least to correlate with, the brad colour.
But the greatest amount of decoration will be the painting on the underside of the lid. My artist friend has offered to do a painting for this, which I am thrilled about. I won't have her start until I'm sure the instrument is worthy, however! The rest will be mainly finished in clear polyurethane, letting the blonde colour of the wood come through. I want it to look relatively plain, a simple "proof of concept" implementation of my ideas, so that the design and the mechanism are easier for interested people to see and understand, without a lot of distraction. Except for the lid painting!
As for the wrestplank, and the bridges. I will drill small pilot holes at the positions of the tuning pins, before I glue the wrestplank into the frame. Thus, it'll be easier to use the drill press to get these holes vertical (I'm not attempting to give the holes a back-angle, as is often done; I just want them to be consistent). Then, I'll glue the wrestplank into place, and finish it with polyu. And then, I'll drill out the tuning-pin holes to their final diameters, probably using the handheld electric drill. Thus, the sides of the holes will be raw wood, not finished (which is necessary for the right kind of friction on the tuning pins).
I will drill small pilot holes in my oak moldings, with the drill press, for the bridge "pins". Small nails, in my case. Two moldings, one for the nut, one to become the bridges. After drilling the bridge molding, I will dice it up into individual segments; then I will glue the bridge segments into their places on the soundboard,
All this before the polyu, so that there is good Titebond conditions. After the polyu has fully dried, back at the apartment, I will install the nails into all the holes... and then, I'll be able to begin installing the strings and the tuning pins, which will be one operation. Wow, sound! A ways to go yet, but it's in sight. I'm now quite confident that the tone will be adequate, and less confident but still *fairly* confident that the structure will be strong enough, and won't just collapse immediately or within days, of coming under tension. Just from my instincts, my "tapping tests", and my general visceral sense of how strong the structure feels, now that I can physically interrogate it.
Oh yes, and about that link.
This page, among other things, makes me think that good tone is obtainable from a simple design employing plywood. My aim is really just to create a hammer dulcimer with a keyboard. The construction techniques and materials don't have to be the same as were used in 17th century harpsichords, to still sound good. I hope...
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