The weekend of September 6th, 7th, and 8th brought the annual Fair in the Park in Pittsburgh. For anyone unfamiliar with this event, it’s a three day arts fair put on by the Craftsmen’s Guild of Pittsburgh. The event features artists working in ceramics, fiber, glass, metal, jewelry, leather, and wood. Every year, the western Pennsylvania chapter of the American Association of Woodturners, Turners Anonymous, has a booth, not to sell, but to show work from members and demonstrate.
With Fridays free from the 9-5 job, I signed up to spend the day in the booth talking to folks and demonstrating. There were lots of wonderful folks that stopped by to talk art and woodworking, watch shavings fly on the lathe, and look at the works on display. I also had the chance to browse the wonderful artist booths throughout the park.
In preparation for the event, I wanted to put together a few example pieces to show what I would be demonstrating. I considered small items like pens and stoppers, as well as candle sticks/holders, bowls, and boxes. However, I decided that I wanted to try my hand at a musical instrument.
I remembered an old episode of the Woodwright’s Shop from the 1980’s where Roy looked at different traditional African instruments. One of the instruments, a mbira or kalimba, could be as simple as a board with metal or wooden tines set to be able to vibrate. Adding a resonating chamber to the board helped amplify the sound. So, if a box is all that was needed, why not a turned box? I obtained a tines and bridge hardware and set about trying to figure out the size for the turning.
Kalimba #1 was made out of cherry and ended up a bit small. Additionally, the kit that I had obtained contained one inch screws, suggesting a need for a rather thick sound board. This first box was made with that in mind. The result is a much smaller resonating chamber and a quieter instrument.
Kalimba #2 was made from Hormigo (also called Orange Agate, Macacauba, or Macawood), a central american hardwood. I’ve worked with this wood several times before and find it to be easy to turn. It also accepts a very nice finish. The sound board was made significantly thinner. Due to the initial size of the blank, I was left with a relatively small instrument that could only accept nine keys. It has a very nice sound and handles very well.
On the first day of Fair in the Park, I had an opportuntiy to demonstrate the making of the instrument. The process is fairly straight forward for anyone that has turned a lidded box before. After placing a bowl blank between centers, I turned down the blank, shaping the outside of the bowl and adding a tenon to the foot to allow the bowl to be placed into a four-jaw chuck. Once the outside was turned and sanded, the bowl is reversed placed into the chuck. The top of the blank is then flattened, taking care to remove any piercing from the spur center. Once the top is flattened, a lip is turned into the top where it will be fitted to the bowl. After the lip is established, the top is parted off. The cherry blank used for Kalimba #3 was larger than #1 or #2 and I did not have my handsaw with me. This made parting off a bit of a chore.
After the top is parted off, the next step is to start hollowing the bowl, taking care to establish the side walls so that the top will fit snuggly. Once the walls are established, the rest of the bowl can be hollowed out and sanded. Finish, if desired, should be applied to the inside of the bowl at this point.
Once the bowl is finished, the top inside lip of the top is coated with an epoxy and fitted to the bowl. After giving the epoxy time to set, I then cleaned up the transition between the bowl and the lid. The lid is then flattened, the sound hole drilled, and pilot holes for the screws for the grounding bar are also drilled at this point. The entire bowl can then be removed, flipped around, and placed in cole jaws to remove the tenon and clean up the bottom. Final finishing can then be applied. After the finish is cured, the grounding bar, bridge, and tines can be added, and the instrument given its first tuning.
Kalimba #3 was made from cherry. The top was made significantly thinner and the bowl much thinner, resulting in a larger resonating chamber. The sound quality remained clear with the ability to amplify sound much better.
Kalimba #4 was made from sapele. The initial process for this was the same as the prior three instruments. However, I wanted to obtain a perfect grain match. The sound boards for kalimbas #1-3 were each made by flattening the top of the intact bowl, creating a lip on the outside of the bowl, and then parting off the top. The top was then flipped over and placed into the hollowed bowl. This resulted in an inability to get a perfect grain match.