A while ago I was contacted by Philippe Chretien who had invented a “Fibonacci Clock” and asked if I would be interested in helping him fun his Kickstarter campaign to develop and manufacture them. It was amazing how quickly he raced passed his funding goal and raised over $181,000.
Philippe’s Fibonacci Clock seemed to strike a geeky chord in all of us. Telling time by using the mathematical Fibonacci Sequence is both beautiful and absurd! Briefly, the clock has no numbers, only values related to changing colored squares. It changes every five minutes and requires you to do a bit of simple arithmetic to determine the time.
It’s a great conversation piece and has several display modes so you can use it as a cool high-tech lava lamp, randomly morphing colors, if you prefer. Philippe is taking orders for his next round of clocks. You can get it as a complete kit with a CNC cut wooden enclosure, or just get the electronics and build your own box. Frankly, this would be a perfect CNC project: making all the little grooves by hand is a bit challenging. Nevertheless, here’s how I did it.
Making a custom enclosure
I wanted to use up some curly redwood I’ve had in the shop for a long time. To make the four sides of the enclosure, I cut the pieces with 45° bevels on their ends so I could build the box using miter joints.
There are a lot of precise slots to cut on the insides of the box for the dividers to slide into. (A CNC would be so useful here!) Of course, I used my table saw. This mainly requires carefully planning how to cut them, in what order, and running a lot of tests. In the plans I have included lots of measurements to help out. It is also extremely important to mark the orientation of each board so you don’t get them confused.
I used very thin 1/8″ (3mm) plywood for the dividers. My regular saw blade was slightly too thin, so I used a blade from my dado set which gave me a perfect fit.
The it was just a matter of setting the blade to cut through about half the thickness of the wood and making the grooves, triple-checking my measurements each time.
I also cut rabbets along the two long edges of each board to hold the back panel and the front, plexiglass panel. Once all this was done, I dry-assembled the enclosure, holding it together with a strap clamp. Then, I marked where I would need to cut the back plywood panel to fit into the rabbets.
Using my table saw, I cut the rear plywood panel, the center plywood panel (which holds the lights), and the translucent acrylic (Plexiglas) for the front.
Cutting the thin dividers to fit into the slots on the sides is easy.
Cutting grooves in 1/8″ material is not easy! Lots of testing to ensure they are about 1/16″ (1.5 mm) deep. (Did I mention how much easier this project would be with a CNC?)
Eventually I got everything to fit! Then I traced squares on the center panel so I would be able to tell where I needed to drill holes for the lights.
Hooking up the circuit board is easy. Just three wires to screw in.
I cut a rectangular hole in the back panel for the four buttons to fit through.
As it turned out, the 1/8″ plywood was too thin and the circuit board wouldn’t seat properly.
So I used 1/4″ (6mm) plywood and cut away parts of its surface to allow for the irregular surface of the circuit board.
Next, I glued the box together, using glue on the miters. The light panel just floats in the slots without any glue. I also glued in the little dividers.
Darkening the edges of the dividers with a marker will make the divisions between the squares stand out better behind the translucent Plexiglas.
After spraying several coats of lacquer on the box, I popped the LEDs into place and screwed the back on.
Finally, I glued the translucent acrylic into the front rabbet using just a few drops of all purpose adhesive.
But how do you tell time with the Fibonacci Clock?
No worries, Philippe included a handy card in the kit. It’s not difficult, and it actually kind of fun! As a former homeschooling dad, this would make a great learning tool for kids.
Note: my plans are based on Philippe’s original Sketchup drawing and modified to fit my situation. They are not perfect. I suggest you review his plans if you want to make your own enclosure. All of Philippe’s materials are open source and can be downloaded here.