Well, I finally finished all the posts. Quite a read, took about 2 months!. However, in those months, I was inspired to do a custom bass from what I've learned here. I've had to switch to upright bass this year (I bought an NS Design NXT) and since I had business trips coming up, I began to think about a solution for a portable upright bass. The trip was a month away when I started the build, and I decided to use as much of the stuff I had laying around the house to build this. I call it the Very Small Double Bass... VSDB. The idea was to have a bass that would be played vertically.
The neck ( removable) is left over maple from an EUB project I'm working on. The sides, nut, bridge, 'tailpiece' and pickup enclosure are purpleheart, another leftover. The back is Brazilian Cherry (left over), and the top I actually bought from Stew Mac... it's western cedar. I wanted an organic sound for the top. The bass also has an internal JFET piezo buffer/preamp that is turned on when you insert the guitar cord.
The neck is kinda interesting. My first thought was to make the bass headless, not knowing squat about the Pahoehoe string stretch (hadn't got very far in the threads... duh.) so I designed a method for doing that, that will work quite well with metal strings, and not in a million years with the Pahoehoe's due to the incredible stretch. So I rummaged through my old parts bags and came up with some Fender style tuners, and one of them had a relatively small base plate, which I cut down even further to fit the small amount of room I had on the headstock (remember I'm using leftover wood...) and one had really wide tuning posts, and they fit together! The neck angle can be adjusted to change the string height, and of course, it comes off for packing in my luggage.
Also, the neck size, and profile of the back of the neck, and of the fingerboard, are duplicates of my EUB neck from the nut to about the 10th 'fret' position... I used one of those profile gauges to make sure, so it would be easy to transition between the two instruments.
First problem out of the box was how to keep then strings from slipping out of the tuner slots, a problem which I overestimated maybe, but the solution was simple. I drilled a ¼ inch hole down the center of the tuning posts, and tapped the hole with a ¼ – 20 thread, then dug up 4 of those brass knurled knobs from an old telescope project, and voila! Self locking tuners! You can't believe how much this has helped with putting strings on and off. I think in the course of this build, I've had those strings on and off over 20 times easy.
I used two Radio Shack buzzer piezo's under the bridge, they are sandwiched between two strips of bicycle inner tube rubber, wired in parallel to the buffer. The bridge floats on top of the top rubber layer. It's got a removable battery type box too.
The weird shape was done to allow the bass to sit between the legs while sitting in a chair, like when chillin' after dinner in a hotel room... This works fairly well, especially when I have the rubber tailpiece stub on it (helps the wood from slipping on the chair seat). The body indent is meant to fit against the leg, and the smaller bit by the tailpiece is pressed by the other leg, thus it'll work right or left handed. I did put a 1/4-20 thread insert in the bottom of the instrument, for the nub, and for fitting on a tripod or whatever.
True testimony: I took it to a rehearsal, and played Cantaloupe Island on it. The bandleader loved it, he was quite astonished, and asked me if I could get my EUB to sound like that... (now please don't take this as an indictment of the EUB, turns out he is a little hard of hearing, and he wanted my EUB volume up).
The acoustic unamplified sound, oddly enough, does come through in the amplified sound, I can hear the top in the character of the amp'd tone. Pretty cool.
The VSDB is not finished, I still need to inlay some good dots (current dots are just stickers I punched out) and I want to bind the top, and then apply a finish, but I have to wait till spring, as I can't spray in my house.
This was (and still is) a great fun build, and now I have a nice portable DB to take with me when I travel.