Not much else to say.
So my next project: A nice, good sounding electric bass.
I got things more-or-less put together tonight. I need longer axles; 20 cm was about 8 cm too short. But anyways, I now know how everything fits, and how the top will have to interact with the furnishings. Designing that will be simple.
The top will only have bridges pressing on it. The Keybox will not touch it. The top will have a perforation for the wheel, and another one under the keybox that will be accessible for when the axle or wheel need servicing or replacement. There will be minimal bracing– just enough to support the bridges, and something to prevent dry cracking in wintertime (something I have found is needed here in Minnesota — I’ve lost some mighty fine guitars to the dessicated air from December to February).
The top will vibrate freely. I am happy with how it looks in my mind’s eye.
I recieved some feedback about the layout and spacing of the keybox vis-a-vis the wheel, and realized one more iteration would have a positive effect. I built a third keybox, and incorporated the criticisms; I also lengthened the outboard extent of the keybox so I could dress it up a little. Instruments that look good sound better. I don’t know why, but it is so.
This week, time permitting, I will try to mount the wheel. Once that is done, I can figure out the top layout and bracing design.
So I roughed in the keybox so it can be dry-fitted to the body; and also began installing bracework to support the wheel.
Tomorrow (time permitting) I will create the vertical brace the wheel bearing will sit in, and perhaps dry-fit the wheel. Once those items are all laid out, I can plan the top, its perforations, and its bracing.
Until now most of the stuff I’ve been doing has been very similar to building an acoustic guitar, which I have experience with. Now I’m getting to a new phase.
Today I slapped the first keybox together and realized:
- the square holes are too small; the square rods would not have enough meat for the job they have ahead.
- The 2 rows of holes are not far enough apart form each other, and the top row is too close to the top of the box.
- I sill haven’t figured out how I’m going to make the ‘Talents’, the little fingers that press against (and fret) the strings when the keys are pressed. They have to be strong and solid, and also adjustable in the fore-and-aft and side-to-side dimensions, so the instrument can be intonated correctly.
So I made a second Key box, with bigger square holes, correctly placed. I’m going to need to brood about the talents for awhile. The ‘keeper’ is the one laying down. I’m still going to keep working the discard, so I can make fabrication mistakes on that one and then do things right on number 2.
That’s the way Design-Build goes. You have a good idea, you execute it, then you figure out it needs someting more. Fortunately this instrument is modular — more modular, say, than an acoustic guitar. I can make subassemblies and perfect them and if they don’t work, figure out what’s wrong and make something better.
Today I drilled the square keyway holes for the keys to fit in, roughed in a wheel or 2 some more, and I have a nice pair of cedar blanks gluing up for the top. Progress!
With the loose parts all to hand, I can play around with how things have got to fit together, and from there I can figure out how the top bracing needs to be designed to support everything and still allow the top to resonate.
I’ll try and figure out the ultimate siz of the key box and begin assembling it. That will really drive a lot of other design decisions.
So in the end, I heated up the bows again and let them cook awhile, so unrelieved stresses would be resolved.
Using bent linings, as is my wont. One side done:
The other side is now set up and drying:
Because I may be experimenting with unusual tunings on this instrument, including some that are higher tension than the more common C/G that most players use, the additional longitudinal rigidity lent by the bent (as opposed to kerfed) linings may be of benefit.