We at NakagawaGakki are always looking at new ways to make sound more portable and interesting. The idea of a necklace capable of rockn da house was the inspiration.
If you have time on your hands and the nuts, then you can make one too.

You will need:
Walnuts
Small handsaw
Sandpaper
Wire
Hair pins
3mm thick hardwood
wood glue
Hand drill
Contact mic (if you want to make your necklace LOUD)

OK lets get started...

(If you want to skip all of the following steps then you can always visit our Etsy Store to purchase one of our exquisite Kalimbas!!!)

Step 1: Split and Flatten Ya Nuts!

Ok, easy enough you say, but first you will have to decide if you want to crack them or cut them.

You can try cracking a few with a hammer, a nut cracker, your hand or your head but you run the risk of not getting a clean/straight line and/or injuring yourself.

We prefer cutting them down the seam with a hacksaw or small hand scroll saw. If you decide to do it with heavy machinery the normal precautions apply.
Please be careful of your fingers.

Take a break, eat contents of opened nut.

Next is to make the surface flat.
Lay out some medium grit sandpaper on to a flat surface like a hard table top.
You can use a little doublesided tape to keep it from slipping.
Slowly run your walnut across the sandpaper in a straight line away from you.
After a short time (walnut is quite soft) the surface should be as flat as your table...

It might be good idea to clean out the refuse in the interior of the nut unless you want your kalimba necklace to double as a maraka.
Hey come to think of it, thats a great idea!!!

Step 2: Cut the Top Plate

This is done with a Hyoutan (Japanese Gourd) but the principle is the same with your walnuts.

Lay your walnut flat down onto your 3mm thick piece of hardwood. Any wood (except Balsa) you can get your hands on will be fine. We chose maple for this step.

Trace a line around the outside of your nut with a soft pencil to show you where to cut. Keep it near the edges of the wood to save cutting time and limit material wastage.

With a scroll saw cut on the outside of your pencil line, all the way around until the piece is completely cut out.
It should fit nicely up to the flat face on the nut.

Step 3: Make the Bridge

There are many potential ways to do this. Its important that the tines don't touch the topplate directly and that they are secured tightly down to produce a good note without buzzing.

The easiest way we have found is using two pieces of wire secured to the topplate and one tube screwed down over the top in between the wire pieces, sandwiching the tines. Picture is of the Hyoutan again, but the walnut has the same procedure.

Cut your tube no wider than the topplate. Brass tube is perfect, you can try aluminium rod or thick wire, just experiment with what is easily available.

Next you have to drill two holes big enough for you small bolt to just pass through. Its easier if you secure it in a vice, not too tight though...
Once you have finished drilling file the ends and make sure there aren't any burrs anywhere.

Secure each of the the two pieces of wire into the topplate by drilling two small holes, bending the wire 45degree about 5mm from the ends and pushing it through the holes. Should be a tight fit but it doesn't need gluing or anything.

With the securing of the top tube. Place it in between the two wire bridges and mark where the holes are. Again drill two holes just big enough for your small bolts to slide through. Remove the bolts and the top tube.

With some epoxy glue, glue the two compatible nuts onto the underside of the top plate, that is the OPPOSITE side to the bridge wires. Becareful not to get any glue onto the threads and make sure the nuts line up with the holes in the topplate so the bolts can be screwed down easy.

Leave the glue to dry for a few hours.

Step 4: Cut the Tines

You'll need to "borrow" 6-8 metal hairpins from your Mum, Sista or significant other.

The blue tensile steel hairpins give the clearest tone and they often come with a hard enamel dipped end on them for kalimba players' sensitive fingers.

Usually the hairpins have a smooth side and a rippled side. The smooth side is what we have used but you can try with both. I'm intrigued to hear the sound the ripples make, vibrato perhaps!!!
You can always cut some more and swap them later.

Cut them as long as you can but just before they bend around.
File the edges round to avoid scratching.

Step 5: To Amp or Not to Amp

It is here you must decide whether you want a LOUD necklace or delicate accoustic necklace.
Its quite easy to fit a piezo pickup if you have a soldering iron and the parts.
Just follow the first step of this Instructable
You only need the lead to be about 40mm long and a minijack (3.5mm)terminal will fit into the tiny walnut better than a giant 1/4inch one.

Pictured Kalimba is of Bamboo but procedure for walnut is the same.

The minijack terminal needs to be secured by drilling a hole through the walnut shell. The easiest place is at the "bottom" of the kalimba. The area that faces you as you play the instrument. Its better here so the terminal doesnt interfere with the bolts coming in through the topplate at the "top" of the kalimba. Things get tight in there when its all glued together.

After you have wired up the pickup and tested it you can screw down/in the terminal.

Now is also a good time to fit your necklace. We use leather but you can use nylon, cord or chain. Drill two holes through the walnut shell at the top and pass your necklace through.

Step 6: Finishing Up.

Now that the glue on the bottom of the topplate has fully dried you can now start fitting the tines.
6tines is usually the best for such a small instrument but it really depends on the size of your nut!
Place your top tube between the wire bridges and pass the bolts through the hole in the tube and the topplate until it reaches the affixed metal nut on the bottom side.

Screw in the bolt 2-3 turns and start sliding your tines in. They should go over the wire bridges but under the tube.
When you have them in the desired position tighten down the bolts evenly until the tines start making a clear tone when you strike/pluck them with you thumb nail. Don't tighten them too much and don't worry so much about their tuning at this stage. you can do that later.

If you have a piezo pickup installed affix it to the bottom of the topplate with some double sided tape. You may need to trim it if its too big.

Use some good quality PVA wood glue to glue the topplate to the walnut base.
If you can clamp it with a bull clip or wrap some string tightly around it the glued joint will be much stronger.

Wait 12-24hours before unclamping.

Filing the edges will give it a finished more professional appearance.

You can tune each tine with a guitar tuner. Sliding the tines in and out adjusts their tone. Further out (long) is a lower tone, in (short) is a higher tone.

Now plug it into your Hifi, stereo or dock and make some necklace noise.

If all of this is too much you can always visit our Etsy Store and purchase a readymade!!
http://www.etsy.com/shop/NakagawaGakki

Thankyou.