There is something daunting to the novice about making stringed instruments. They look hard to do, but you can make a dulcimer, particularly if you can borrow one to copy. You will do well to copy one that you like, but if you prefer, you can follow the dimensions 1 give here and end up with another one like the one I borrowed. The process I describe should adapt to any design. If you have a good guitar shop nearby, you can usually arrange to get hold of a dulcimer for long enough to copy it, and you can buy strings, fretwire, and even pegs. This leaves you with eight or fewer pieces of wood to shape and glue together into a box that sings.
Any good instrument begins with good wood that has been given enough time to dry. You may even cut a tree with the instrument in mind. Split pieces for the sides, head, and fretboard from a green walnut log, thin them down, and put them away. Salvage an old poplar board from a hog pen to use for the face and back. Clean it up and bring it inside to dry. It all starts with good wood, you add the drying, and then you shape all the parts and glue them together.
Start the head (called the scroll if you use the traditional snailshell carving) by sawing its outline from a 1 Winch-thick piece of walnut (or maple or whatever hardwood you wish). The scroll is the traditional finial for a violin, but as a decoration, it could just as well be the carved head of Elvis. The peg hollow is the place in the center of the head where the strings wind around the tuning pegs. Lay out the hollow with a double-toothed morticing gauge, making sure to leave the side walls at least 5/i6 inch thick to give the pegs sufficient grip. You can rough out the peg hollow quickly by boring in at the scroll end with a 5/s inch auger, sawing down along the grain, and then finishing up with a chisel.
Whether you like the looks of your head or not, without well-set tuning pegs your instrument will not be playable. The pegs are simply levers that allow you to increase or decrease the tension of the strings and wedges that hold the adjustment once it's made. Achieving the friction fit of the gently tapered pegs requires considerable patience and care. It is possible to buy or make matched peg shavers and reamers that make the job quick and easy, but 1 took the advice of a violin maker and bought viola pegs at an instrument shop and fitted them by trial and error. Drive a peg in hard and turn it so that it leaves shiny places on the interior walls of the peg hole, then carefully remove the shiny spots with a rat-tail file. There is a point of no return at which the hole becomes too big for the peg to fit tightly. For this reason, it's a good idea to finish the head and make sure its pegs are in working trim before you join it to the other parts.
The head and the tailpiece connect the sides like the stem and stern of a boat. The sides meet these pieces at an angle, which can be formed with a saw kerf or an open shoulder. The saw kerf will glue up without clamping, but it makes later repairs tougher.
"The Woodwright's Eclectic Workshop" By Roy Underhill
© 2012 The University of North Carolina Press