As a long time musician and music lover I'm always looking for new ways and sounds to express myself, and just a few weeks ago I became interested on the cajon sounds in particular. Me being me I was not about to go to a music shop and buy one, nooo!, Instead I went the diy way and this is the result. You can find the link to my drawing with the cajon measures at the end of this instructable. I hope you like it!
1/4 sheet of furniture grade pine plywood, 15mm thick
1/4 sheet of furniture grade pine plywood, 5mm thick
4 pieces of oak for the corners
1 length of walnut veneer for the front and back tapas
41 1" drywall screws
4 rubber feet
Minwax fast drying poly satin
Tablesaw, router table, drill press, cordless screwdrivers
Step 1: Wood Cut to Size
Before cutting anything I made a plan on Illustrator, always do that with all my proyects. I had all the wood from previous proyects laying around so I just picked up what I had at hand, in this case some plywood and oak, and some walnut venner. Went to the table saw and in a few minutes the wood was ready.
Step 2: Routing Dados Into the Wood Sides
After checking all the 4 pieces where the same length, I did one 3/8" x 3/8" dado on each corner, with a straight bit on the router. That's where the side panels fit.
Step 3: Routing Rabbets Into the Side Panels
The router table was setup to leave a 3/8" rabbet on the the top and bottom sides of the panels.
Step 4: Test Fit
It was time to make a dry fit, it worked almost perfect, just had to sand a bit here and there but otherwise it worked as planned.
Step 5: Cutting Tapas to Size
Then I made the cuts on the 5mm plywood to get the front and back tapas, as my tablesaw and sled are small, I had to get a bit creative to make the long cuts. The cuts were made a bit larger than the final size, You'll see why later.
Step 6: Cutting the Veneer to Size
I took the veneer, looked for the best pattern and measured it a bit larger than the tapas so it would overhang some, placed some masking tape to protect the edges from breaking and used sissors to make the cut.
Step 7: Gluing the Venner to the Tapas
"Can't never have enough clamps" they say, and it was almost true this time!
After spreading yellow glue into the tapa, I placed the venner taking care of the alignment and carefully sandwiched the tapa/venner between some pieces of plywood, then went to do something else while the glue dried.
Step 8: Rounding the Corners Edges
While waiting for the tapas to dry, I went to round the sides of the cajon with a roundover bit at the router table, made several small passes turning the cajon around to match the curves on both sides.
Step 9: Gluing the Cajon
After the tapas dried I proceeded to glue the cajon, went first with the bottom panel + the corners, then the side panels, then the top panel + corners, the photo shows the last step, just waiting for the glue to dry again.
Update: added a drawing to show you where to apply the glue on this type of joints.
Step 10: Making the Sound Hole
As the back tapa was too big to fit on my drill press I had to get creative again. I found a good piece of 5mm plywood that would fit on the drill press and made a pattern so I could make the sound hole at the router table.
After the hole was ready, I took the pattern and glued it on the inside of the back tapa, to reinforce the hole as it is used to carry the cajon... one stone, two birds :)
Step 11: Fastening the Tapas
After carefully measuring the spacing and location of the screws to hold the tapas in place, the whole drill/countersink/screw dance started, 41 screws and one battery recharge later, it was done!
Step 12: Shaping the Tapas Borders
The overhang on the tapas was left so I could route them to the shape of the cajon with the pattern bit on the router table getting a better fit.
Step 13: Adding the Rubber Feet
Next, the rubber feet were screwed on the bottom. Just marked the proper placement, drilled a pilot hole and that's it, fast job. Then into the varnishing.
I went with minwax fast dry poly satin applied with a piece of foam in thin layers, I prefer the look and feel of this, instead of thick and shiny.
Step 14: Cajon Finished!
And this is it! As I had some stickers with my monogram from another proyects I added one to the cajon as a finishing touch. Later on I will add strings or a snare wire, haven't decided yet which sound I like to go with, but it sounds pretty good as it is.
Here is the link to download my drawing if you are interested, if you build a cajon, let me know ;)
Thanks for reading, and I hope you liked the instructable ;).
Step 15: Small Update: Snare Wire
So, for the time being I'm testing the cajon with a snare wire, it sounds good , maybe too prominent and there are some harmonics when tapping it so I may have to tweak the placement of the snare wire a bit to find a sweet spot, mabe add some sort of muffler.
Btw. thanks to everyone reading and adding this instructable as a favorite! I have a new one to publish soon ;)