So there it is, the "mountain banjo." Now you can tell why I want to make one. In this post, and others to follow, I will document my construction so you can learn from my ideas and especially my mistakes. I have to admit, I'm not doing this on my own. Randy Cordle's free plans and construction advice posted on Bluestem Strings are what I'm modeling my banjo after. The following youtube video was also inspirational. I hope to document my work in a little more detail than the video for those who are not familiar with woodworking (although I am no expert). I have also heard that the Foxfire Book III hard plans for a banjo like this, but I don't know for sure. Sadly, I don't own that book.
Today, I wanted to gather some materials and at least get the pot started. I wanted to use scrap and salvaged materials in order to keep the cost low and also because that is how these banjos were often made. People used what they had. I didn't have any 1/2" solid stock wood but I did find some scrap 7/16" birch ply in my garage. It is not traditional in the sense that it is ply, but it is very traditional in the sense that I'm using what I have on hand. Of course, I had to make some minor adjustments to account for the missing 1/16" but that wasn't too hard. I'll also have to figure out how to seal the plywood on the side, but that is a challenge for another day.
The first thing I noticed when looking at the plans was how many circular cuts must be made. Instead of using a jigsaw, scroll saw or coping saw (which would all work) I decided to use a router so I could get a nice clean, almost perfect circular cut. To help me, I decided to create a simple jig. It looked a little like this.
|My jig is shown here. The router is bolted to the top board. The nail holds the jig to the board below but allows the jig and router to rotate above the board. By rotating the router, I was able to cut nearly perfect circles.|
The jig was nice because it allowed me to make nearly perfect cuts. I can also save the jig to quickly create parts for a second banjo if I like how this one turns out. The cuts come out nicer if you make multiple, shallow passes with the router instead of one or two really deep passes. The exact depth will depend on your specific router and the wood you choose. Just start shallow and experiment around a little. It is also important to cut the outside circles first. This way, when you need to make the inside cut, you can still attach the jig to the center of the circle. Of course, if you don't have a router or you don't want to make a jig, you could always use a compass (or even a pencil and string) to draw a circle and then just cut it out with a jigsaw or coping saw.
When you cut the top and bottom pieces of the pot, you can use the router and jig to cut the curved part of the outline, and a saw to cut the straight part. Sometimes I offset my cuts by 1/16" or 1/32" and then sand the wood down to the final size. It reduces the risk of accidentally cutting into your piece. Of course, you could accidentally sand too far into your piece too, but sanding is easier to control than cutting.
|When you cut out the top and bottom pieces of the pot, do not cut a complete circle. You need to leave a little material for the rectangular shaped part that the neck screws into (see plans). I'll cut the inner part of the circle out later.|
|Here are my two circles before I glued them together.|
|Here they are again, now arranged as one unit. The router really helped to make them uniform, but I'll sand them down to an even closer match later.|
|Here they are again, glued, clamped and waiting to dry. Note the wood scraps that I placed between the clamps and the circles. They prevent the clamps from leaving impressions in the circles.|
|The three pieces that will later form the pot.|