When I started this project, I had no idea of what the end result would be.
I had a guitar neck from a cheap guitar that had a plywood fret board. I removed it easily and stripped the neck. The heel was a little messed up so I glued a piece of mahogany to the end, so I could have a clean surface to shape for the neck to rim fit.
At this point I was thinking of using a teak salad bowl for the rim. It was 11 1/2 inches in diameter. So I calculated a scale length of 19.5 inches.
I wanted to make it into a banjo with a tunnenled 6th string. I was thinking of using gBDGBD tuning for it.To tunnel the string I cut a groove in the neck from the 5th fret, under the nut and into the peghead to the tuner. After slotting the fretboard I glued it in place using a piece of lightly greased earphone wire from a broken set. The wire was just the right size to provide a channel for the string. Because I greased the wire first, it came out easily.
The salad bowl was not working out, the back was too thick and deadened the sound. Also it developed a tiny crack along the grain. It was cut from a single piece of teak. I put the project aside while I contemplated the problem. When I came across the cookie tin with a 12 inch diameter I decided to use that instead - inspite of the "lovely" still life on the lid. I believe it was meant to be used as a tray as it is heavier than a standard lid. The inside also bears the same graphics.
I had salvaged a large turnbuckle that had been used on the large eucalyptus tree we had cut down, and although it is a bit of overkill for a banjo it did work. I had to purchase a 6" bolt to use on one end as it wasn't quite long enough. Coordinator rods and turnbuckles both work because the threads of one end are regular threaded and the other reverse threaded. That was a problem because I needed a reverse threaded nut to secure it to the rim. Fortunately the ends of the turnbuckle are threaded for at least 3/4ths of an inch allowing me to cut 1/4" off the reverse threaded end for the nut. That is on the tailpiece end.
The tin itself was a bit on the thin side, so I lined it with three layers of luan mahogany plywood doorskin. The top edge is beveled to make a thin 'tone ring'.The problem with doing this is that the tin's rim turns inward, and made it impossible to slip the wood inside and get a tight fit. I bent three strips of the doorskin and fit them individually inside one another. Once they were fitted, I left the outer ring in place, lined it with Saran Wrap and glued the inner two rings together. To clamp them I used large binder clips closely spaced. Once they were glued together. I removed the rings, clamped them together and shaped the top edge. Once that was done, they were put back inside the tin and glued in place. With that the rim was sturdy enough, especially with the lid/resonator on. To enable me to assemble it, the lid had to be removeable. As the tin is only 1 1/2" deep, the lid had to be notched to accomodate the coordinator rod. The lid slips between the heel and the rim.
For a tailpiece, I salvaged the tailpiece off a small Mexican guitar. That is just screwed into the end. The nut was cut from a dogbone i have for that purpose. The tuners are the original 3 on a side cheapies that came with the guitar. For strings I used a set of Vega mediums + the 4th string from a tenor banjo.
This banjo has a unique sound. "It almost rings like a bell" is how my husband describes it. A long sustain.
It also has intonation issues. Ugh. I have worked on the nut, fiddled with bridge placement, and still have a problem with the 3rd string in particular. The lowest bass may be too heavy a gauge, as it seems off. I think I will try a set of guitar strings, maybe nylon. I have to work on the nut more, as it just isn't right yet.