Today we're making a Christmas tree ornament using Sugru. Once the Sugru sets, we'll add some color changing LEDs.
At the moment, this is a work in progress. I will add the final steps once the Sugru has hardened.
Bill of Materials
- 1 multi-color package of Sugru
- 1 small balloon
- 1 2032 battery
- a few multi-color LEDs
- Some bits of wire
- 1 small binder clip
Notes on the BOM
The LEDs blink in different colors with no additional circuitry. I bought mine from ebay pretty inexpensively. Search for "rgb flashing led." You're looking for 2 pin LEDs, not 4 pin.
Step 1: Making Green Sugru
I wanted to make a red and green ornament. However, Sugru isn't available in green. I made my own green by mixing 2 parts white with 1 part each blue and yellow. After working the Sugru for a minute or two, I obtained a nice shade of green.
For the size ornament I chose (about 4" diameter) and the pattern I laid out, I used 1 packet of white and a half packet of the blue and yellow. I split it all in half and rolled it around in two separate batches.
Step 2: Rolling It Out
I put a few strips of painters tape down to roll out the strips of Sugru. I found that it stuck a bit to both acrylic and wood. If you don't have painters tape, try a cutting board.
Rolling the Sugru out took a little patience. I was going for nice, even cylinders to stick to the balloon. If I rolled a spot to thin, I would simply fold the strip in half and start rolling again. It remains pliable for quite a while so there is not urgency to get it done. Work the material until you get the results you're looking for.
dry 24 hours.
Step 4: Adding LEDs
To prepare the LEDs, I bent the leads directly away from the bottom of the LED in opposite directions. Make sure you remember which one was longer. The trick that worked best for me was to bend the leads on the LED a certain way. The anode (+), which is slightly longer than the cathode (-) was bent in a tight hook so that is was flat when viewed from the top. The cathode is bent into a loose hook vertically.
Once that is done, I started with one LED and pushed the leads between the balloon and the sugru. I wrapped the bigger hook around the Sugru and then engaged the small loop from a second LED and pressed them together with a pair of small pliers. I continued around the ball until I had all LEDs in place. Do not connect the last two open wires.
Step 5: Pop the Balloon
Before you pop the balloon, you'll want to be sure the Sugru is not sticking to it. Push the balloon away from each piece. This will keep your Sugru ball from imploding when the balloon is popped. I chose to carefully untie the balloon to let the air out slowly. Once the balloon is deflated, remove it.
To power the LEDs, I needed a stack of five 2032 cells. Because the LEDs are connected in series, it requires a fair amount of voltage to get them all to fire up. I taped the stack of cells together with electrical and inserted the wires into the appropriate ends of the stack.
I plan to make a themed battery holder to print on the 3D printer that I can suspend from the middle of the ornament. For now, I use the battery to hand the ornament.
Please enjoy this short video of the LEDs in action. https://www.youtube.com/watch?v=Fp4qh389vXc