After seeing what Instructables gurus like bumpus, jwilson37, and freeza36 have done with Altoids tin "diddly bo" guitars, I remembered an old rectangular candy tin in my bedroom closet, and thought I'd try to make an instrument out of it. I'm not that interested in the guitar, but a ukulele appeals to me, so that was what I decided to go with.
- Tin box
- Poplar trim board
- Additional wood
- 18ga copper wire
- Sheet metal
Those were all on-hand in my shed and basement. In addition, I purchased:
- A set of six tuning machines ($16)
- A set of Aquila Nylgut ukulele strings ($6)
- Woodcarving knife (I used my trusty Leatherman Wave for most of the carving)
- Wood rasps
- Surform plane
- Needle files
- Dremel with assorted attachments
- Vise (I used a Black & Decker Workmate)
- Jeweler's saw
- Coping saw
- Keyhole saw
- Table saw (I really did use every single one of these, but could probably have gotten away with hacksaw, coping saw, and handsaw)
- Power drill
- Electric woodburning tool
- Tin snips
- Wire cutters
- Tape measure
- Set square
I looked at several Instructables and some online cigar box guitar plans, all of which I reference at the appropriate points, but if you have any interest at all in building something like this, you need to join the Cigar Box Nation.
Fair warning: This Instructable will not end with a video of me whaling away on my brand-new uke. I did produce a functional, even beautiful-sounding instrument, but I don't yet know how to play it. One of my purposes in creating this build was to give me a teaching instrument so I could learn to play. So far, I'm still working on keeping it in tune and fingering a couple of basic chords. EDIT: I've gotten better. See my "National Library Week" video on YouTube!
Step 1: Planning and Design
Ukuleles come in four basic sizes: soprano, concert, tenor, and baritone. The main difference is the scale length of the instrument, that is, the length of free vibrating string from bridge to nut. If I used Shelley's plan and attached the strings directly to the tail-end of the neck, a soprano or concert uke would have to have a comically shortened neck, and I'd need to extend the fingerboard over the tin box body to have enough frets to play with. Given that, I initially planned a tenor uke.
The more I played around with the design, though, I realized that the bridge would still be close to the edge of the body. I wanted it nearer to the midpoint, so that as much of the box lid as possible would vibrate. That's when I hit upon the idea of attaching a tailpiece such as banjos and resonator guitars have. That gave me much more geometrical freedom, so I settled upon a concert-size uke with a metal tailpiece. It turned out to have very nice proportions.
I also chose a trapezoidal headstock that ran parallel to the neck. In the final version, this is causing some trouble with string alignment above the neck, so future builds will have an angled headstock.
Step 2: Primary Woodwork
This scrap wood was some of the same material I later used for the fretboard. A house near ours has been undergoing a complete renovation. The builders appear to have taken everything out of the house, piece by piece, and replaced it as they went along. I've been scavenging in the construction dumpster (with permission) and pulling out as much dimensional lumber as I could find. The house was built in 1910, so these 2x4s are more than 100 years old. Based on the strong piney smell of them, I'm guessing they were fir. Whatever the wood is, it's dark, close-grained, carves like frozen butter, and reveals a beautiful coloration. I'll definitely be using more of it for other projects!
I cut out the neck with handsaw and keyhole saw, cut the additional fingerboard piece and chose my scrap, and then sanded and glued them all up into a wooden sandwich. After the glue had dried thoroughly, I went after it with rasps, the Surform plane, and my knife to round off the back and create a smooth transition from neck to headstock. I could have sanded everything smooth, but I like the whittled look. I think it will take on a rustic patina with use.
Step 3: Box Prep
Step 4: Tuning Machines
Step 5: Fretboard
This would have taken a lot of wire, and carving those curved diagonals was going to be fiddly. One of the CBN folks suggested adding a separate fretboard, and I realized that would solve several problems. It would give me a good surface for the frets, It would raise the strings up high enough that I could make a decent-sized bridge, and it would extend a little over the tin and mask the seam where it met the poplar fingerboard, which was unattractive. This is what I went with. I sliced off a nice piece of 100-year-old 2x4 with my table saw, whittled it down to the proper size and shape, and then wrapped the wire around. I used multiple short-ish pieces of wire, rather than one long one. For each, I filed a perpendicular slot for the starting end, then diagonals from fret to fret, ending with another short slot to accept the bitter end. Once all the frets were installed, I glued and clamped the board in place.
Fret placement, by the way, is a surprisingly easy thing to determine. Stewart-MacDonald has a great fret calculator on their site, but as I was digging around on forums, I discovered the astonishing FretFind 2D tool. This allowed me to print a perfect diagram that I was able to glue to the neck with temporary adhesive. I used that to cut slots on the sides for the wire to ride in. This worked beautifully.
In the future, I may find that the wire develops some "play", especially when the wood reacts to temperature and humidity differences. I might need to add a couple dots of superglue to keep them in place. For now, though, they are working great.
Later in the build, I added some aesthetic touches in the form of fret markers. These are dots at frets 3, 5, 7, 10, 12, 15, and 17. The double dot is at the 12th fret, where each string should be an octave above its unfretted pitch. I put large dots on the face of the fretboard and smaller ones along the top of the neck, where I can see them without craning over as I play. These were added with a woodburning tool.
Step 6: Nut
While I was in the process of mulling over my plans, before I'd even started the design process, I went on a campout with my son's Boy Scout troop. While on a stargazing outing with the boys, I found a bone hidden in some tall weeds. At first glance I thought it was a skull, but closer inspection revealed it was a coccyx. It had been out in the elements for a long time, and the bone was dry, devoid of organic material, and sun-bleached white.
On the same trip, I found some cow bones scattered around one of the grills at our campsite. Someone had obviously cooked short ribs and left the bones on the ground. Like the coccyx, these bones were picked clean and dry.
The nut for my ukulele was a piece from that found coccyx. I cut it down to size with a hacksaw and filed off the rough edges. Placing it at the proper height on the fingerboard involved some more whittling, but it eventually seated itself nicely. When the uke is strung, the pressure of the strings keep it in place, but I put some glue on it just to make sure.
Step 7: Tailpiece
Step 8: Bridge
- String "action" (space between the string and frets) should increase from nut to bridge, because when you are pressing the string onto a fret, it shouldn't contact higher frets.
- The tin lid had a fair amount of give, and when everything was strung, the bridge pressed it down.
I'll be re-making the entire bridge soon. For now, it's shimmed up with toothpicks. This makes the uke playable, and also makes it easy to adjust the bridge to compensate for the different ideal scale lengths of each string.
Step 9: Stringing
This is another reason for making a new bridge. I filed slots in the nut and saddle to accept the strings and keep them from sliding back and forth. I had a false start on the saddle slot for the G string which allows it to jump sideways when strummed too vigorously.