Make a small banjo played with a plastic slider bar that is secured on the neck and is easily moved
under the strings with one finger while strumming. Hawaiian steel guitars use a heavy steel bar on top of the strings. A fretless boards is used in this banjo. Time to make is about 5 hours. Use re-cycled materials.
Helpful hints are found in Mistic instructable dated 3-19-10" Mini banjo for kids." High polymer elastic strings are used through-out. This results in easy construction by kids and students.
Step 1: Materials [see Figure]
Wood- Neck made of any wood available. size 3/4 x 1-1/4 x 7 inches long. widths of 1-1/2 can be used.
Resonator case or enclosure.-- Any available can or plastic bottles or food containers. We use aluminum pet food cans 3-1/4 x 2 in. high and small sizes ones 2-1/2 dia. shown here. Also , we found a drink bottle you can buy for about $1.50 at places like Walmart.It was a one liter 'h2o on the go' 4 in. dia, cut down to a 2 in. height.See figure.Dog food cans have a sharp edge where covers were ripped off. this should be flattened with a small plier.
Nut, bridge and slider - Wood used or plastic or tubes of plastic as soda straws. Dowell are 1/4 and 5/16 dia, for the slider.
Slider- base-- plastic, hard . Use old gift or credit cards of .o3 thickness cut to size and bent with a plier.
Strings-- Polymeric high elasticity 1mm. dia . size. A 15 ft. spool is available at Micheals Art sup. for $2.50.
Crimp- tubing , bead or eyelets are available in Micheals .Inside diam to be at least .075 in..[2.5mm.].Supplied in small packages.
Tuner screws-- 5/8 size with a collar, brass plated steel. named Cup-hook..4 ea. per small pack.
Finish paint - laquer, clear hard. on the slider surface of neck.; wood can be any stain and finish. Clear finger nail polish works fine and dries in minutes.White surface can be correction fluid bottle with a brush.It's fast dry.
Pen-permanent type markers.Use to mark the notes on the fretless top surface.
Glue- High temp.type is best due to strength.
Step 2: Tools
Hemostat type plier---- with a locking forcep and length of 4 in. or more for grabbing the pulled string in side the case and holding in place so crimps can be attached.
Knifes- exacto and a short strong knife for cutting harder plastics.
Ice pick or awl--- Can be the hobby type witha sharp point and handle. Use to punch holes in case.
Scissors- strong type for cutting plastics. small for cutting string,etc.
Drill- Drill stand or Dremel drill , hand-held. Use bits of .078 or .106 dia. depending on wood used. Soft pine needs .078 dia. for the tuners to be tight . Hard wood as oak uses .106 drill holes.
Hand saw. to cut wood. Small vice for holding wood to cut angle for tuners location. Also to cut plastic.
Glue-gun. Small size that can melt HT glue sticks. E6000 glue is also good for adhesion of plastic to slider.
Step 3: Construction-
Beginning construction- There is no hard or fast rule on how to begin construction. The following is used when a can or plastic resonator is used as no deep effort is needed here.
Neck--Soft pine or decorative pieces of oak as found at hardware stores.Cut one end at approximately 45 degree angle for locating the tuners. Sandpaper smooth. Do the final finishing with stain, lacquer,.Drill two tuner holes spaced about 1/2 in. apart. Drill with .078 drill if pine wood.all way through.. Lay aside.
Resonator- Using the food can. eliminate all sharp edges with a plier.Use a scissor and cut a one inch wide opening in a side opposite the neck about 90 degrees or so. This the sounding hole. Punch about 6 small holes inword in the area that will be attached to the end of the neck.These holes will be filled with hot glue later when attaching the neck to the resonator can. This gives great strength to the assembly.Hole dia . about 1/16 in.
Attaching - Lay the neck and can upside down flat on a surface so the plane of the neck is same as the can surface. Glue some melt on the wood end and the prepunched holes, and rapidly push together and let cool. this is now assembled. Cooling should be for about 10 minutes.
Bridge and Nut-- cut to length and hot glue in place as shown .Not critical where the bridge is but should be about 1/2 inch from the 2 pre-punched holes for the string in the can surface. Same for Nut. Apply lacquer to the dowells after glue.The two holes need be about 1/2 in. apart and about 1/16 dia., smooth all sharp edges of the two punched holes with a knife or sandpaper.
Tuner- Preclose the open ended rings with pliers. Start the screws into the pre-drilled holes. This will probably require aid of a pair of gas-pliers for screwing in.. screw in about 3 turns till collar is flush to wood surface.Torque should be about at the point where you must use a plier to turn.
Slider- It is explained in the drawing. I used an old gift card cut to size top and two sides as shown. Use a straight edge of long nose plier and bend two side feet as shown. Place a 5/16 dia. dowel on top and hot-glue. Lay aside.
Stringing.--Cut a piece about 1 ft. long. Place a crimp tube of inside diameter at least big enough to size two
strings into on tube onto a n end of sting about 2 inches up. draw the end through the eyelet of the tuner and back into the same crimp. Hold and snug up . then pliers crush or crimp the tube . This now is attached . Next, wind 3 turns counter-clock wise around the screw collar top and keeping the tension run other end into the appropriate hole in the can surface. Use the locking plier or hemostat inside of the can after feeding string from above through
the hole and also pulling from underside. Stop and pluck the string for the sound you want. In this case I pull untill I am close to the Note A.. Lock the plier close to the can at this point.Obtain a crimp with a plier. Pass it as close to the can and locking plier. Crimp it. Remove locking plier. Cut off excess. You are done with one string. Now go to the C note string [ string no.1.]In this case I used Piano center C. Final tuning is done with the tuner later on after the slider is in place.
Slider-Attach the slider under the strings. This is easily done since all that is necessary is to lift the strings as they are quite elastic. Test smoothness of the slider down length of the wood..It should glide easily while you strum.
Pick use-In some cases you might use a pick to strum. I glued a small can at bottom to extend the can body so my wrist lays on this extension so I can apply the pick.
Next is the final tuning.
Step 4: Tuning-Playing
The strings are pretuned near the note you want a s described. To tune the two string banjo You need to push the slider up to the neck top or nut.Now you can tune with the tuner to note - C at string one. and A note at string two.
You will notice that the note are not stable. This is called drift in string instruments. Thsi drift downward about a note or two will be compensated by retuning. The drift is maximum after an hour after a sting is stretched. Re tuning is minor.
To find the D note of string one slide slider down to note D while plucking .Wait about an hour before this scale operation to let the drift effect settle.Use the marker and mark on white surface point D at edge of slider.Continue all the way to final note F. This finishes the scale. You also do this to string No.2.
Playing- Strum or use a pick to play while moving slider to the desired note.
You can lay it flat on a table or lap. or vertically using you two fingers while strumming with a thumb.
Kids can play directly from a music score . Playing by ear is also easy and lots of fun too.
The picture shows my large Uku. with the slider in place. See the three MOvies MOV
Another picture shows the smallest banjo in the universe. Only 5 inches long, one string. and one-and 1/2 octaves. It can actually play. No slider needed here.
For more volume I have amplified the banjos with a standard ear bud inside the case resonator. I found I needed a bottom on the can of plastic to get a greater volume also. I used an old CD and glued it on bottom of the can.
The ear bud or an old headphone fed into my stereo set which had good microphone pre-amplification built in.
A wireless mike worked fine feeding into my FM set at 107 Mhz. The Hana-Montana Mike was purchased on the internet at Amazon.