I'll let the pictures do some talking:
I used the jigsaw to cut a hole in the top of this high-quality plywood half-sized guitar which I acquired inexpensively from the Goodwill. One can easily find similar examples sold under names such as First Act, Mark II, and many others. I often wonder about the Chinese luthiers knocking these things out by the thousands .
Do they go home to create an instrument of their own personal vision? I'd like to find out some day.
I reinforced the top using some chunks of Doug Fir, aiming for a resonator-style soundwell sort of construction. This works fine, but next time I have the head off, I think I'll add some supports at the tailpiece end, too.
The smallish bits glued to the back are cut out of the top brace, they're intended to hold this next part up off the back a bit:
For an internal tension hoop/tonering, I cut down this artisanal oyster sauce can from the dumpster behind the Thai restaurant. See how it fits so nicely:
I like that galvanized finish. My thinking is that having the ring supported off the back a bit allows more sound to escape into the body to bounce around and out the soundhole. The resonant and overtone-rich sound I've been getting supports this hypothesis.
The tackholes are already there because I took these pictures during a head-changing session. The previous head was some scavenged x-ray film, which proved a little too floppy. I'm trying out a piece of PET plastic cut out of a cake container here. I'm told you can shrink the film up tighter with a heat gun if need be.
I recommend punching the holes with some kind of sharp tool instead of just trying to push the tacks through with your thumb, unless you have Bruce Lee hand strength.
I really like the look of those brass furniture tacks.
I cut a swoop into the headstock to omit the 6th tuner and visually indicate the banjo's five-stringedness, and ditched the dinky OE tuning machines for some decent ones I ordered from StewMac. Now every time I look at it, I have an unfulfillable craving for Pokey Sticks. I am aesthetically delighted by the massive knothole in the center of the headstock. I believe more builders should try including such a stylistic feature.
The fifth string is tuned at the headstock and tucks under this unique capo device at the fifth fret. Note high-quality Harmony inspired stencil markings. Yes, my housemate made me aware later that I should have placed a marker at the 10th fret instead of the 9th.
And there you have it! Probably about twenty bucks plus a few hours of spare time invested.
It makes an excellent traveling banjo; you wouldn't lose sleep or even flinch if you had to bust it over some troublemaker's head outside the Greyhound station.
Next time you're at the Goodwill, grab a five dollar First Act and make one for yourself!
I think I might paint skulls and monsters all over this one.