First find a piece of straitish knot freeish wood about 3 and a half inches wide (90 mm) or more and half an inch thick or more and about 14 inches long or more. I got mine from a section of a plank taken from a shipping palette. A longer plank will give a longer ukulele. I have made a 2 foot long one (which is a Tenor Ukulele) using a virtually identical method and a standard soprano as well.
You can see how they sound here
First is the sopranino tahitian style tuning (apologies for the fat fingers)
Second is a tenor Uke tahitian style tuning.
Third is a regular tuned soprano uke all made using roughly the same method.
Step 1: Mark Out Your Uke
Mark out the shape you want for your ukulele. I am going for as simple a shape as I can because I am a little simple myself.
The scale length here was going to be 20 cm but finished up being 22 cm,or around 8 and a half inches.
Step 2: Excavate Out the Back
Now turn the Uke over and mark out the area that needs to be hollow. Then have at it with your preferred method of excavation. For this small one I decided to go manual and used a chisel. Remember a plane is just a chisel held at a particular angle with a guide to stop it from taking too much off at once, working patiently from either end with the chisel and occasionally using a sharp knife to clear the ends and work on inside of the sides.
It is much easier to do this with a router.
Even I was not perfect and had to glue a crack back together.
If you don't feel up to the hollowing task you can just cut a hole and use something else as a resonating membrane. Heat shrunk PET bottles work magnificently.
Step 3: Test That It Makes a Good Sound Before You Go Further
An important step is that you have to test that you are getting resonance from the sound board you are paring down to. Put a string over the board and make sure it makes a clear and pleasant noise before you stop excavating out the back of your front piece. The thinner the board the more it will resonate but the more likely it is to break. I tend to go for around 4mm thick.
Step 4: Make the Back
Now take a small piece of wood the size of the back, put a hole in it and hollow it out - This is a tahitian style uke so the hole is in the back. You can put the hole in the front and make it an interesting shape if you like. I have done groovy sound hole shapes including a possum, a corgi, a turtle and a dolphin holed uke. If making a groovy sound hole shape just remember that wood splits along the grain so keep the shape simple or be prepared to reinforce it or explain to people - it used to be an octopus but now it isn't.
Step 5: Glue It Together and Cut the Shape Out
Glue the back on - (not sure why mine decided to crack) cut out the shape, plane, and sand and smooth off thoroughly. I went all medieval on mine with a belt sander.
Step 6: Shape the Headstock (put a Lean on It)
Now cut the Headstock at an angle - I reused the off cut to make the back of the headstock, just gluing it on. Because I was a little messy with the cutting I filled the front with a filler which should have matched but didn't
Picture no 2 is of a headstock on one of my other Ukes where I used a slightly more aggressive angle - a second piece of wood and a face plate- for looks.
Step 7: Put on a String Anchor
Now I add a bent nail (recycled from the same shipping pallet as the original plank) to attach the strings to the back, sanding out a small hollow to make the staple not snag on anything. If you are not fussy any ole thing will do as a string anchor from a 1/2 inch screw to a wooden peg to a 4 inch roofing bolt.
Step 8: Add a Nut and Mark Out the Frets
Now I add a nut to the front and mark out where the frets are supposed to be. It is important to get the height of the nut slots fairly close to what the height of the frets are. Too high and it is hard to play and too low and the strings touch the first fret and buzz. If you cut them too deep a bit of super-glue in the slot can help sort things out. (Remove string from slot first and replace it when glue is dry).
Type"fret calculator" into the search engine of your choice to find the lengths you need. An accurate measure is a definite must here. with this short scale length, being only a quarter of a millimetre out will make it sound horrible. The tenor length Uke (440 mm scale length) is more forgiving. A small tip is to mark the sides a little as well as the top so you can see how the frets align with the marks after the fret is on top of the marks on the face of the fretboard.
Step 9: Stick on Some Frets
I made these frets by splitting bamboo toothpicks, and scraping the back flat/ off further with a sharp stanley knife. It will be helpful if your frets are all the same thickness and cut to length before you glue them on. If you use super glue it helps to harden the frets so they do not split or wear down as quickly. This one is glued with standard white woodworkers glue.
Step 10: Add Tuning Pegs
I cheated a little with this build and used ebay bought tuning pegs. See my other instructible for making wooden tuning pegs.
Step 11: String It Up and Play It
Now make a bridge with small notches in it about 7 or 8 mm high. It will probably have to go a small amount further from the nut than originally planned as the tension in the strings increases as the string is pushed down to the fret and having the bridge further away compensates for this.
I strung this uke tahitian style with 20lb (0.42mm) fishing line and tuned it to CFAD tuning with the top D being re-entrant - only a tone higher than the bottom C.
The fingering is then identical to a standard ukulele only the chords are as if you were playing with a capo on the 5th fret ( 5 semitones higher).
After a few more experimental models, I now go for a 27cm (11 inch) scale length on my sopranino ukes and tune them in octave over guitar tuning (DGBE) with the top d two octaves above the guitar using 40,60, 50 and 30 lb fishing line. This makes switching between guitar and my various Ukes a tiny bit easier on my old brain.
Also here you can see a couple of other examples of where experimenting with these things can take you. The Hootowlele is made using almost exactly the same method as here but has a traditional fret board, a more decorative shape and a standard length, while the spongebob biscuit tin uke has the octave over guitar tuning.
Acknowledgements and inspirations:
The sunshiners from Vanuatu
I like this guys work
The guys on the Duckworks wood boat building Yahoo group/forum who provided lots info wood mangling, glue strengths, metal working and getting on with it over the years.
These guys have a pile of info on their site as well:
If there is a patron saint of home made musical instruments made from any and all available materials it is this dude:
Found this instructable most useful
If this guy can make a sopranino ukulele then so can I
And of course the Ukulele Orchestra of Great Britain and Jake Shimabukuro.
Don't want a Uke?
Try a pocket violin