Smiling Pendant With LED Eyes (in the Style of the Def Con Jack)

When your outfit needs a little extra flare, this bejeweled smiley face with LEDs for eyes will do the trick. A conversation starter in any setting, with brightness adjustment to make sure it is always alluring and not overpowering. Plus, the "smiley" resembles the Def Con Jack logo. As someone who has to wear a tie and coat at work occasionally, I like to have the Def Con flair going for me.

You will need

• The pre-made jeweled face from a hobby shop (I got mine here)
• A PCB board (option), but I made it to make and sell these with more reliable connections, etc. I made a prototype with a simple Coin Cell and some LEDs (see below). The Fritzing File for the PCB is attached if you want to mass product your own!
• Coin cell holder
• Coin cell
• Switch (optional)
• A 10K Potentiometer (again not required, but I included for brightness control)
• LEDs. For the final production, I used the LED Sequins from Adafruit in Red, Green, and Blue.

And a soldering iron, solder, wire cutter, etc.

After purchasing the Brooch, I broke off the pins and then got a Dremel tool to grind down the mounts for the pins and also ground out the eyes. I think this piece was made from cast aluminum. Make sure to wear hand, eye, and breathing protection, as it makes lots and lots of tiny bits of metal. I tested it out with a simple coin cell holder, a couple of spare LEDs, and some cardboard. 

I wanted the LEDs to be as flat as possible. There were some variations in the brooches, so I decided to do something different and make a "bar" for the positive and negative LEDs instead of a through-hole mount. BTW, don't try to wire the LEDs in series because the variations in the LEDs are significant enough that one will be brighter than the other. This design allowed me to solder the LEDs as flat as possible and, if needed, move them a few millimeters to compensate for differences in the Brooch. I first put some solder on the bottom bar, then melted the LEDs into the bar, positioning the LED itself in the center of the hole in the PCB. I then soldered the top. After that, I quickly added the remaining components and tested them. I held up to the "Smiley" to ensure the LEDs were in the center of the eyes and made any adjustments to the LED locations.

The final step was to use 5-minute epoxy to very quickly glue the PCB to the "Smiley" face and also glue on the backing. (By the way, I tried jewelry glue, and it reacts with the PCB; don't use it!!).

Let me know if you make one. And if you would like to buy one from me, you can find purchase here.