This is a little display that I tossed together to illustrate some of the fun light shows that can be made with an RGB LED by using a microcontroller to generate different patterns and colors. Enjoy!
Step 1: Light Source Selection
Pick a light source. I am using a custom RGB LED driver board with several 'canned' blinking modes (ColorBeam RGB LED board from "Tindie"). However, this project would be great for you to program using, for example, an Arduino. I like the custom board as this display is just for fun and I don't have to tie up one of my Arduino boards to run it. Turning on/off an LED (or 3 if RGB) using an Arduino is well explained in many places, so I won't do that here.
Step 2: Make the Structure
Create the pyramid frame. Here I used an existing "Calibration Pyramid" as can be found on Thingiverse: (Thing number 8757). The structure has the advantage that it was designed with a solid base, but is a framework for the rest. You can also make one in a similar fashion by folding up a paper or cardboard cutout of the same size and cutting out the 'viewports'.
Step 3: Color It
I used Testors model paint to color mine gold (it started as white). I wanted something that was reminiscent of the gold pyramid spacecraft on StarGate. I used a cotton swab and gave it a couple of coats. Don't go overboard with the paint as a little goes a long way. It is better to put more thin coats down than one thick and goopy one.
Step 4: Drill a Hole for the LED
You could do this before step 3 if you like. I did it afterwards so that the hole for the LED could be as smooth as possible and not filled up with any paint. I measured the outside diameter of the LED with some calipers and then got a drill a bit larger. If you buy an LED, the vendor should supply data on the size, but may only state the LED size designation. You can look up what that translates to on the web. Don't worry if the hole for the LED comes out a bit too large, you can always wrap a little bit of transparent tape around the base of the LED to snug up the fit. The ABS plastic I used for the 3D print is pretty slippery, so a closer tolerance works fine.
Step 5: Make the Diffuser
I used a light source that has a non-diffused envelope, so the light tends to come out as a spot. This is worse since I used an RGB type and the emission spots from the individual LEDs don't quite overlap perfectly. I had first tried to make a set of diffusers that would be stuck from the inside but that was too much 'ship in a bottle' for me, so I cut a set as one piece (see PDF file for template) that has the size about right for just friction fitting into the structure. If you use the file, you will have to play with the magnification to get the fit right for your pyramid. Once you cut the template out, then cut out a diffuser using parchment paper or wax paper. It can be tough to trace onto either, but I had sufficient results using a fine point Sharpie pen. I left the bottom intact (no hole for the LED), so actually the light gets diffused twice: first at the very bottom and then again at each side panel (spacecraft viewport!).
Step 6: Insert the Diffuser
See the picture for assistance. Insert the diffuser and then spread out the legs away from the pyramid. Then fold them back up and use the friction with the frame to keep the diffuser in place.
Step 7: Insert LED and Admire
You can now insert the LED from the bottom. You will need a little ring or box underneath to space the bottom of the pyramid from the surface on which it will rest. Light 'er up and enjoy! I have this running in the lab on one of our workbenches . It is somewhat hypnotic to watch and the colors cycling through the visible spectrum is quite pleasing. Set your pyramid next to your model jaffa and you are all set for wormhole adventures!