The project I was most excited about was my plan to create some kind of artistic glowing LED Centerpiece to go on each table for our Reception. I had picked up a bunch of hurricane vases and originally thought of using those with a bunch of LEDs and polyfill clouds. But while arranging for flowers at "Flowers and Weeds" I saw that they had these mini terrarium globes, and I thought they looked very beautiful and a little Sci-Fi, and I decided that incorporating them would be the easiest way to add some organic beauty to my electrical art. I had also seen a few projects around the internet that used ping-pong balls as LED diffusers, and I thought they would make nice floating planets/stars. With an arduino and some breadboards I created the first mockup.

Next, I wanted to make my first forey into creating my own custom PCBs. I figured it would save me money and look better than buying a bunch of arduio boards and LED drivers. I started in Eagle to create my board, but there was a steep learning curve, and I realized I wanted to get creative with the design, so I exported it to CAD, and 5 iterations later had this design:

My first attempt was to use the toner transfer method, but since is was such a large board I didn't have much luck.

So instead I decided to try a method Ryan had come up with. We used a powdercoat gun to add a layer of toner to a board, and then put it in the laser cutter on lower power.

It melted the toner to the board, and since I had used autoCAD i was able to split it into a combo of fine outlines and engraving outlines for the big ground planes.

wash off the un-melted toner and you are left with a beautiful etching mask!

To Etch away the exposed copper I decided to try the Hydrochloric Acid and Hydrogen Peroxide method. At first I didn't think I would really need to agitate more than swishing it occasionally. But it was taking longer than I wanted (even with the ad-hoc bristle-bot agitator).

Swishing seemed to help the most, and since I was at the Hackerspace it was a piece of cake to whip together a simple auto-agitator. It served its purpose gallantly, and a dozen boards later it was quickly returned to the scrap pile

Drilling out all the pin holes was pretty easy, as the bit nicely centered in the copper rings I had made (as opposed to full copper pads). Using the Dremel drill press also worked better than the large one in the shop, as I think this was the smallest drill bit I've ever used.

Soldering the 4-pin LEDs to the stiff red wire was rather tricky. I wanted the connection point to be as small as possible, as it was very visible, which meant heat shrinking each wire individually wasn't possible. So instead I design and 3D printed a bunch of these separator rings. I just trimmed the LED legs and wires and inserted them in from either end, no further insulating needed. They actually had a pretty good frictional fit, but I still dabbed on a little solder, then covered it up with a single piece of heat shrink.

The wedding was quickly approaching, and I finally had one assembled! I had a small 12v Lead Acid battery in the base for power, as it was cheap, long lasting, and added some good, stabilizing weight. The Ping pong balls worked really well, but I recommend scuffing up the outside of the LED as well.

Its a late night of testing, and you can hear my frustration that it isn't working as I expect. I'm also starting to realize that I'm running out of time. The microcontroller seams to be running slower than it should, and possibly resetting. I suspected heat was the problem, as the LED driver was getting really hot. I later learned that there was a heat sink pad on the bottom of the chip that I should have soldered to a large ground pad. Instead I had stuck on a heatsink and lowered the power a little, and I was able to at least get a nice slow random color fade going.

In the end I was only able to fully complete 3 of the centerpieces with the ping pong ball planets. I decided I would use the best one for the head table, and all the rest were a made a little simpler.

Each table had a different Sci-Fi/Fantasy theme/Planet. A Sandworm from Dune, The Aliens from Pizza Planet (Toy Story), The Arcade cabinet from "The Last Starfighter" (Rilos), The Tardis from Gallifrey (Dr Who), Marvin the Martian from Mars, The Statue of Liberty from the Planet of the Apes, The Tree of Souls from Pandora, Luke's home on Tatooine (Star Wars), Robbie the Robot from Altair 4 (Forbidden Planet), the Ouran from Fantasia (Neverending Story), and a Horga'hn from Risa (Star Trek).