On a bit of a whim, I decided to build a Cajon.
A Cajon -- spanish for box/crate/drawer -- is a box-shaped percussion instrument, originally from Peru. You play it by sitting on it and tapping on the front in different places. If you check google and/or youtube you should find plenty of info and videos.
As I said, this was a bit of a whim. I can't play one, and no one has asked me to build one. I just was watching a few videos online about Cajons and thought it would be a fun quick and easy project. My son (the future musician) might have some fun with it, or I might end up loaning it out or even giving it away.
In broad terms, there is not that much to say about the design. It's a box about 12"x12"x18" (30cm x 30cm x 46cm) with a hole in the back to let out the sound. My own design was based a great deal upon the Steve Ramsay (Woodworking for Mere Mortals) Cajon build and I also drew from a Lee Valley tools newsletter article by Serge Duclos.
I'm building it with spare plywood that I have laying in the shop. The front is 1/8" oak "door skin" plywood. The rest of it is Baltic Birch, mostly 19mm (3/4") thick, which should be nice and strong.
Here it is glued and clamped together. BB takes glue very well, even on the edges, but I did plough shallow rabbets in the top + bottom pieces to help lock things together
I picked up a drum snare kit for about $10 at a local music store. It was then cut in half, and the two halves are mounted as shown here. A piece of angled pine is mounted to a plywood scrap, and the two bits of the snare are mounted on it. The angle is so that the wires press against the tapa for the snare sound.
This illustrates how the snare block is mounted inside the Cajon. The tapa is then attached to the front over top of this. This is pretty basic, just a pair of notched boards that the block slips inside -- and you can easily slip it out also. There are many designs out there with knobs and things for adjusting the snare, which I omitted.
I wanted a clean and smooth exterior. For one thing, I like the look. For another, the resulting smooth sides make it a bit easier to pack on a shelf for storage. (I was also making this project as much from available materials as possible, so I was not going to go out to buy hardware.) Bear in mind that this is my first ever cajon. So I wanted to keep the construction simple also. As well, this way makes it easy for me to make changes later, if desired.
You don't need to remove the tapa to access the snare. The rear hole is just big enough that you can reach your arm in, pop the snare block up and out of it's mounts, and then work it out of the hole. This allows you to easily play without the snare, and also to access the snare block and make changes to how it is configured.
Finished: Side and Rear view
I removed the tapa for finishing. Wiped on one sealcoat of shellac. This gives a nice amber tone to the pale BB plywood, and also brings up a nice light brown to the oak veneer on the tapa. This was followed with two coats of Varathane.
Finished: Front View
One final design detail to note is that there are no screws in the top corners. Those corners are left loose so that they can vibrate against the edges. By hitting your hand there you can make a "slap" sound. I read some designs where they sanded those areas back about 1/16th inch (1.5mm) but I just left them alone to start, and they seem to work as is.
More details and photos are on my website, if you are interested.