Building a Cajon (Peruvian Drum Box)

I studied abroad in Chile last year. One of of my favorite nights we had a music party at our apartment and my musician friends set up a cajon drum and hi-hats in the corner.

Corner reinforcements

Surfboard straps doing double duty

View of the corner reinforcements

Towards the end of the night when the people with talent had all had their turn and everyone was lubricated enough with Pisco to want me to play I took my turn on the Cajon while my two of my friends played nylon string acoustic guitar.

If you have never heard a cajon, it is a surprise how nice what is essentially a wooden box with a snare in it can sound. It is perfect for acoustic performances as it is not too loud. Furthermore, it doubles as a seat. Best of all, they are easy to make.

As I said earlier, you are making a box. Standard dimensions are 12″x18″x12″.

The top and sides are made of 1/2 inch birch plywood. The back is 1/4 inch birch plywood and the front (called the tapa) is 1/8 birch plywood. You don’t have to use birch as any hard plywood works, but birch is the standard as it is easy to find and cheap.

You also need 40″ of 1″x 1″ wood for corner reinforcements. Recommendations as to what type vary. I’ve seen people use pine and some say only use hardwood. I used alder as I had it on hand.

First: make the top and sides by cutting them out from the plywood. The important part for dimensions is that the top and bottom are exactly the same length and square and the sides are exactly the same length.

Make miter joints where these four pieces meet, but leave the sides flat as you will simply be gluing on the back and screwing on the tapa.

I cut the tips and sides to size using a circular saw then cut the 45 degree miters with the same saw. However, is you could so that in one pass, especially if you have a table saw.

I test fit all the joints, labeled those that fit best and soothed the troublesome joints with a plane.

Once everything fit, I glues them up with wood glue and clamped them using surfboard tie down straps.

Next I glued in the 1×1(cut into 10″ pieces) into the corners, coating two sides and working them into the corners until the suction makes them hard to move. Then check the joints and the square by measuring the diagonals.

Once the sides set (24 hrs typically) plane the joint faces flat making sure to taper them so the front and back pieces will lay flat.

Next, cut out the back piece of 1/4″ by tracing the existing box directly onto the plywood. As a general note, tracing is always more accurate then measuring if it is possible.

Then cut out the sound hole. You want it to be off a bit off center towards the top, but centered horizontally. You want a hole diameter of 4.25 inches as that produces a nice sounding bass thump.

Glue the back on directly and use something heavy to serve to apply pressure.

Once that dries you can trace out the Tapa from the 1/8″ plywood if you have not already. Cut that out, I like to do so oversize then plane down to flush (the same for the back).

Then mark and predrill holes every 1 15/16 inches around the edge, 1/4″ in from what will be the final edge. You also want to drill out insets so the screw will lie almost flat with the face, but be careful you don’t drill so far that the screw won’t hold the face. Also, start an inch from the sides so you don’t drill a screw into the joint and weaken it.

I used 1 1/4″ number 6 screws, but an inch would be plenty. Clamp he tapa to the fully assembled and dry box then predrill and screw in the screws all the way around.

Finish the box with a light sanding and lightly rounding all edges. Apply the finish of your choice. I’m just going to use tung oil.

Now you have a simple drum. You can mount a snare if you wish. I plan to and hope to post that process then.

Nicholson Bench for a Couch Surfer

View of the twin screw vise and holdfasts

Almost done and upside down

I needed a bench sturdy enough to do hand tool woodworking and with all the holding options that go along with it. I also needed it to be portable, easy to break down or store, and cheap.

Of course the main choice these days is Nicholson or Roubo. I also loved the milkman workbench the Shwartz posted awhile ago. Ultimately I was heavily swayed by Bob’s bench over Logan Cabinet Shoppe. It’s a fantastic blog that I cannot recommend enough: http://www.logancabinetshoppe.com/bio.php.

I combined Bob’s construction lumber Nicholson bench with the portability of the milkman bench to get mine. I got a 2x12x12 and cut into to 6′ sections. Then I made a 2″x12″x4′ long apron out of a halved and glued 1x12x8. I made a support frame out of 2x4s and 1×6 which also serve to stabilize the bench and provide enough thickness for holdfast holes. I cut all the angles by hand. So it was a relief when it all came together as it did.

I screwed everything together as my philosophy as a poor chap is to make everything as reparable, adjustable and salvageable as possible.

I also threw in a home made vice out of bolts and threaded rod. This idea was inspired by the vise on Shannon Roger’s portable workstation over at the Renaissance Woodworker. However, the end result is completely my own creation for better or worse.

Cut the angles with a circular saw

Gluing up the blocks

Here you can see the blocks installed

Holdfast holes in apron for supporting boards horizontally.

A bit about the vise:

I used threaded 5/8″ rod I stumbled across in Home Depot. Everyone recommends acme threaded rod due to the wider threads. Hopefully I wont have problems going from going against that. I used a wide bolt 1 1/4″ long or so as the main support rider. I encased that in plywood as tight and firm as possible. However, I drilled holes in the caps so the rod can move in and out so that you can twist it all the way in and have the apron completely free.

As for the handles, I mortised a 3/16 deep hexagon for the 1/2″ thick nut into the red oak (not fun even after sharpening my chisel) then just did a rough 1/16 rectangle mortise into the plywood. I used a 1/2″ spade bit to find the center with the nut in place, removed the nut and drilled 5/8″ through for the rod. After a little work the handles spin nice and freely without spinning the rod and tighten up real nice.

For the Vise jaw my lady friend suggested i just use a piece of 1×6 pine I had left over from making the apron support. I scoffed saying i should use a hardwood, waited a second, said screw it and went ahead with it. Turns out it works great. The give and flexibility actually makes it easier to really lock down on something. I have large washers on so the handles wont wear away the pine.

To sum up: the vise works great, better than I imagined or hoped. Durability, we shall see, but I am very happy so far.

The bench is also great. Only complaint so far is I did not get the holdfast holes perfectly straight so when i tighten the holdfast the face is not nice and flat which effects clamping effectiveness. But that is a minor thing.

The weight is light enough that I can move it by myself with only a slight chance of a hernia, but heavy enough that it keeps the adjustable sawhorses from sliding around. If it comes to it, I have industrial water jugs I can put between the horses legs to keep them from moving, but it has not been necessary so far.

Next up: some jigs to keep the vise from racking on short pieces, some bench appliances for planing, sawing etc., some celebratory brews.