This harp is easy and cheap to make. It doesn't use tuning pegs – the strings are tensioned when they are stretched into place and they are tuned by sliding cable ties.
Pine (or similar), length 700 mm, cross section approximately 35 mm × 20 mm
Pine (or similar), length 150 mm, cross section approximately 25 × 5 mm
Corrugated cardboard (from a packing box), 380 × 220 mm rectangle
11 cable ties (zip ties); the thin sort are best: 2.5 mm wide and 200 mm long
Nylon fishing line, around 0.55 mm or 0.6 mm diameter, 3.5 m long
Step 1: Marking Out the Bridge
Mark the positions of the four slots on the bridge (the small piece of wood). The diagram shows the positions of the start and end points of the first and fourth slots – the second and third slots are positioned in between at equal intervals (11 mm spacing). The slots are slanted by 7 mm and the ends of the slots are 11 mm from the edge.
Step 2: Cutting the Bridge
Use a small hacksaw to cut the four slots. The positions of the slots have been calculated so that the harp's strings all end up at approximately the same tension.
Step 3: Attaching the Strings (1)
Drill two 5 mm holes through the large piece of wood, 20 mm from each end.
Step 4: Attaching the Strings (2)
Thread the nylon string through one of the holes. Pull it half-way through and tie a secure knot around the end of the wood. Then pull the knot round so it lies over the hole.
Step 5: Attaching the Strings (3)
Take one of the ends of the string; thread it through the hole at the other end of the wood. Pull it to take up all the slack, so it lies along the wood in a straight line. Bring it back round over the end of the wood and tie securely, with a knot that lies over the hole. Now take this string back to the other end of the wood and secure it in the same way – you may find it easier to knot around both strings this time. You should now have two lengths of string secured – both on the same side of the long piece of wood.
Step 6: Attaching the Strings (4)
Do the same with the other half of the string – run it along and knot it, then run it back and knot it (making sure there’s no slack). You should now have four lengths of string secured – all on the same side of the long piece of wood. Make it all extra secure by tying a knot with the two short ends you are left with.
Step 7: Fitting the Strings to the Bridge
Look at the close-up of the finished harp to see how the strings fit on the bridge. Position your bridge on the large piece of wood – it should be offset by about 10 mm (lengthways) from the middle so that so that the sounding lengths of the strings are slightly different on either side. Pull the strings up one by one and fit them into the slots on the bridge. Make sure they are pushed down to the ends of the slots.
Step 8: Making the Soundboard
(1) Cut the cardboard rectangle so that it tapers symmetrically from 380 mm wide at the top to 130 mm wide at the bottom (see diagram).
(2) Poke four holes in the cardboard with the point of a pencil, at the positions shown in the diagram.
Step 9: Attaching the Soundboard
Look at the close-up of the finished harp to see how the cardboard is attached. Use two cable ties to loosely attach the cardboard to the long piece of wood, and one cable tie to loosely attach it to the bridge. When you are happy with the positioning, pull the cable ties tight and trim off their ends with scissors.
Step 10: Adding the Tuning Mechanism
(1) Look at the close-up of the finished harp to see how cable ties are fitted around the strings. Fit a cable tie around one end of the string that’s lowest on the bridge, pull fairly tight and slide it to about 200 mm from the end of the wood. Then do the same with a cable tie at the other end.
(2) Now fit a cable tie around one end of the next lowest string. Pull fairly tight and slide it to about 150 mm from the end of the wood. Then do the same with a cable tie at the other end.
(3) Do the same for the next string, sliding the cable ties to about 100 mm from the ends of the wood.
(4) Do the same for the next string, sliding the cable ties to about 50 mm from the ends of the wood. If you want, trim off the ends of the cable ties.
Step 11: Ready to Go
Adjust the pitches of the notes by sliding the cable ties along. You should be able to get a scale – do, re, mi, fa, so, la, ti, do – with the notes alternating from one side to the other.
Now get playing! As an example of what you can do, here is one of my videos on YouTube.
As time passes, the nylon strings will stretch and the pitch of the harp will drift lower. This may not be a problem, but if you want to raise the pitch you can wedge a piece of wood between the strings and the large piece of wood, near one end, secured with another cable tie (you can see I did this to one of the harps in the video).
[Note for people like myself who worry about these things: Strictly speaking, the configuration of this instrument means that it's not a true harp; it's a harp-zither, like the mvet from West Africa.]