Adding math, electronics and wood working together, what could be better? In this instructable I got my inspiration from the Pi Contest going on right now. The project is a wooden cube with the symbol of Pi carved into it that is illuminated by a RGB LED and a AT-tiny 85 micro controller. The project is ran on an Arduino IDE code that I had modified, see RGB attachment. (If you do not know how to program the AT-tiny 85 this is a great instructable, click here).

I will separate the whole instructable in to 3 major parts, "The Box", "The Circuit", and "Putting it Together".

## Step 1: Supplies Needed

For The Wooden Cube:

-Wood ( I got a big sheet that is 1/4'' thick)

-Pi stencil (found above)

-Wood glue

-Router (to carve out the Pi symbol in the wood)

-Drill gun

For The RGB LED:

1 x RGB LED

3 x 330 ohm resistor

1 x AT-tiny 85

Perf Board

-Soldering Iron

-Solder

-5v AC/DC wall plug

You can buy many of the electronic components from Amazon or Radio Shack.

## Step 2: Step 1: the Box: Top and Sides With Pi Emblem

a) First we are going to make the top and the sides. My idea was to carve the Pi emblem into the wood.

-Use a square (or something like it) to trace a square on the wood that measures 6'' by 6''.

b) Now use the Pi stencil to trace the symbol onto the wood. Here comes the tricky part, you need to cut out the wood. I used a router and a Dremel but there are all sorts of tools that can be used to do this.

c) Once you are satisfied use a jig saw to cut out the square of wood.

TIP: To make the Pi symbol look better use sand paper to smooth-en out the insides.

REPEAT:

Now you are going to repeat the first step three more times. Once you have finished you will have 4 sides that all look the same.

These will be the top and 3 sides of the box.

## Step 3: Step 2: the Box: Back and Bottom

a) Now we are going to do the same thing as we did in step one except we won't carve out the Pi symbol.

CAUTION: THE DIMENSIONS ARE STILL 6 INCHES BY 6 INCHES.

Once you have finished you should have two sides that are blank.

These will be used for the back and the bottom of the box.

## Step 4: Step 4: the Cuircut: Layout

The circuit itself is a very simple one. There are just a few things I want to touch up on. When Working with RGB LED's the longest lead is always ground. Then the next longest is green then blue and then red as shown in pic 1. For the barrel jack we will only work with 2 of its pins. Corresponding with picture 2 we will only use the top and the bottom. As for the attiny85, we will use pins 0, 1, 2, ground, and VCC.

With all of that said lets talk about the connections. First the barrel jack Positive will connect to VCC on the attiny and likewise ground will connect to ground. Then the Red lead on the RGB will connect to pin 0, the green to pin 1, the blue to pin 2 and finally the ground pin to ground on the attiny.

Lets make it happen for real now!

## Step 5: Step 5: the Cuircut: Power

a) Now we are on the circuit part of the instructable.
The first step is to get your dc barrel jack and insert it into the center of the perf board as shown in picture 1. Then solder it.

TIP: Again for the next part the IC socket is not needed but I'm running low on attinys so I like to reuse mine. If you aren't going to use a socket then pretend the socket is just the actual attiny for now.

b) Now you will insert the Socket. If you want, put it straight with the barrel jack for neatness. Once you are done just solder it on.

c) Next you will use trail soldering to connect the positive terminal of the barrel jack (In pic 4 it's the furthest to the right) to the positive side of the Socket/attiny.

CAUTION: PUT THE POWER SIDE OF THE SOCKET OR ATTINY OPPOSITE OF THE BARREL JACK SO YOU HAVE EASY ACCESS TO PINS.

d) Then you will do the same thing but this time with the negative terminal. (the top left as shown in pic 5)

## Step 6: Step 6: the Cuircut: RGB LED

a) Now insert the LED. Remember the connections from step 4. Once you have finished solder it on.

CAUTION: REMEMBER WHICH LEAD IS GROUND, RED, BLUE, AND GREEN.

b) Now for the resistors, connect a resistor by the red lead and put the other by the bottom of the IC. Next do the same for green, you must turn the resistor diagonally to connect it to the second pin to the bottom of the IC. Finally, do the same for blue and again turn it diagonally so it will connect to the third pin from the bottom. Pic 2

c) Finally, solder the red lead to its resistor and it's resistor to it's pin on the IC. Do the same for Green and Blue. Pic 2

d) Ground Pin. This is an easy step, just use trail soldering to connect the ground pin of the RGB to the ground of the IC/attiny.

## Step 7: Putting Them Together

a) All right, first if possible screw your circuit to the edge of the bottom piece. Then get your back piece and trace the outline of the barrel jack and then cut it out.

b) Finally, use the wood glue to glue all of the sides together.

TIP: I DIDN'T GLUE THE TOP SO THAT I COULD HAVE ACCESS TO THE CIRCUIT.

## Step 8: FINISHED!

Let this lamp be an inspiration for you to do math because of it's beauty and glory. I hope you have enjoyed the way this looks a works. Please leave comments and questions, I'd love to see what you think.

Thanks for reading and I hope you have enjoyed this!