Making a Banjo

Note the short fifth string on this professionally manufactured banjo.

The original banjo was probably a calabash gourd attached to a long stick. Banjos can be complex or simple to construct, depending on the skill of the craftsman and the intended purpose. They are characterized by having five strings, four of which run across the soundboard to the end of the neck. The fifth string goes only halfway up the neck, and is usually used as a drone or rhythm part when playing the instrument.

Things You'll Need

• Cylinder (can be a cookie tin, bleach bottle, cardboard tube or shaped thin wood)
• Thin plywood (if using an open-end cylinder)
• 2-by-4 board or 4-by-4 board or comparably sized straight pole
• Strings (strings from a music store or fishing line)
• Tuning pegs (something that can be turned to tighten the strings to tune them)
• Frets (nails or pieces of wire)
• Small blocks of wood, such as pieces of quarter round
• Saber saw or comparable handsaw
• Scissors
• Pattern for neck/fret board
• Sandpaper
• Wood rasp
• Pencil or colored marker
• C-clamps or bench clamp

Instructions

Neck

1. Select a suitable piece of wood for the neck. This can be a 2-by-4 board, a 4-by-4 board, a stack of 1-by-3 boards glued together, or a straight piece of unmilled, seasoned wood. The completed banjo will have a board that runs the entire length of the instrument. The soundboard, which can be almost any kind of box that will reverberate when the strings are plucked or strummed, is attached to one end of the fret board/fingerboard. The actual length of the fingerboard can vary, especially if you are building a backpacker's banjo.

2. 

   Create or copy a pattern (a nice one can be found at Song of the Great Lakes website, which is listed under References) to draw the shape of the neck on the wood. If you or a friend has a banjo, you can use the existing instrument to trace a pattern. A banjo neck is similar to the neck on a guitar, but has a small notch on the upper edge of the neck where the fifth string is attached. Be sure to leave enough thickness in the wood to attach the turn-buckles or other tuning device.

3. Trace the pattern shape on the front and side of the wood you have selected for the neck. Use a saber saw, band saw, or small handsaw (such as a keyhole saw) to cut out the shape roughly. A band saw is the nicest for this work if you have access to one. If you are using a saber saw or handsaw, use C-clamps to fasten the wood down to a bench, chair or table so that it doesn't wiggle around and your fingers are safely out of the way. If you have a workshop with a table clamp, that will also work to hold the wood.

4. Rasp the edges of the rough shape till it is close to being the shape you desire. Finish shaping the neck by rounding and smoothing it with sandpaper.

Soundboard

1. Select the cylinder you will be using as a sound box. This can be a very large cardboard tube (six to eight inches across and at least two and a half inches deep), a candy or cookie tin, a ham tin or a heavy-duty plastic bottle such as a bleach bottle.

2. Prepare the soundboard for attaching the neck. Banjos are frequently left open-backed, so unless your cylinder does not have a top, you will not have to worry about covering the opening. A bleach bottle is probably the easiest to prepare. Cut off the pour spout end, leaving four or five inches of bottle intact. Turn it over so that the bottom becomes the top. One-half inch from the solid bottom (that is now the top), draw the outline of the unshaped end of the neck/fretboard on opposite sides of the bottle. Use a razor knife to cut out the ends and the edge farthest from the solid bottom/top, creating two little trapdoors through which the neck will be inserted. Cookie tins and tubes will need similar notches cut in them to allow placement of the neck. A packing tube will require a thin plywood or similar wood top.

3. Add decorative touches to the soundboard, if desired. If using a metal tin of any kind, be sure to put some sort of protective covering over sharp edges. If possible, turn metal edges (especially if using a ham tin) over in a sort of little metal hem, using tin snips and pliers.

Assembling the neck and soundboard

1. Slide or place the neck into the prepared notches on the soundboard. About one-half inch of the neck should extend past one side of the soundboard. The flat edge of the neck should be facing the same way as the solid surface of the soundboard.

2. Fasten the neck and soundboard securely together. Plastic or metal soundboards can be attached using the little flaps left on when cutting the notches for the neck. A bead of hot glue around the opening will help seal it. Wood or cardboard soundboards can be attached using wood glue. Let dry.

3. 

   Notice the placement of the tuning pegs on this neck.

   Attach small eye bolts, hooks or nails to the end of the neck/fret board that sticks out one-half inch from the soundboard. This is where you will fasten one end of the strings. Place one eye bolt or professionally made turnbuckle at the little bump on the top edge of the neck. Place two eye bolts or turnbuckles on each side of the end of the neck. These will be the tuning pegs for the strings.

Frets, Strings and Bridges

1. Place the bridges on the neck to hold and guide the strings. Bridges provide loft to the strings, and keep them from moving out of place while playing. One bridge should be on the face of the soundboard. The other should be on the narrowest part of the neck, just before it widens out to hold the tuning pegs.

2. Saw shallow cuts across the neck to hold the frets. Placement of the frets is critical to noting the banjo. Dennis Waring, in "Cardboard Folk Instruments" (page 52), gives the following placement for frets on a neck that measures 23 5/8 inches from the bridge at the tuning-peg end of the neck to the bridge on the face of the banjo, starting from the tuning-peg end (measurements are in inches): 1 11/32, 2 9/16, 3 3/4, 4 27/32, 5 29/32, 6 7/8, 7 53/64, 8 11/16, 9 1/2, 10 9/32, 11, 11 23/32, 12 3/8, 13, 13 37/64, 14 1/8, 14 5/8, 15 5/32, 15 5/8, 16 1/16, 16 1/2.

   Dan, of Song of the Great Lakes website, recommends buying a ready-made overlay for the fret board and gluing it to the neck.

3. Hammer or glue the frets into the slots on the fingerboard. You can use small nails or pieces of wire to create the frets. Add any decorative touches desired to the fingerboard.

4. String the instrument. Use fishing line or professional banjo strings from a music store. Fasten the "eye" end of the string to the eye bolts or other device at the body end of the neck. Stretch the four main strings across the bridges to the tuning pegs at the other end of the neck. The fifth string will fasten to the tuning peg on the little bump on the neck.

5. Tune the strings. When the banjo is held with the body in front of the player's stomach, and the neck stretching toward the left, the bottommost string is known as the fifth string. There are many different ways to tune a banjo. Individual banjos (especially a homemade one like this) may need special tunings to have a good sound. One standard tuning that is a good place to start if the banjo is not a familiar instrument has the bottom string tuned to a high E (just like a guitar). The fourth string is a B, the 3rd string is an E that is one octave lower than the high E, the 2nd string is a G#, and the 1st string (that little short one) is a B.

Tips & Warnings

• If you are interested in constructing musical instruments, visit your local library. They will have many good books on making and playing musical instruments.

References

• Cardboard Folk Instruments, Denis Waring, 2002.
• Song of the Great Lakes Woodworking Site: Build a Banjo
• MMIF: Building a cookie-tin (backpacker's) banjo
• Boy's Life: Make your own banjo

Resources

• Videojug: How to make a banjo out of a balloon