Originating in China, fireworks have been around since before the 16th Century and have been making people look to the night sky with delight. Firework formulas are closely guarded secrets handed down from generation to generation and the overall concept has not changed much over the centuries. Mix chemicals compounds, place them in a delivery device, light a fuse, and watch the fun. That was until now of course. At Soldering Sunday we wondered if we could use LEDs to create a firework display? The answer is a resounding yes, we can!
While there are thousands of forms fireworks, we focused on the aerial fireworks that make the big displays in the sky. Aerial fireworks have several components: a lifting charge to send it in the air, a container which holds the stars, charges, and fuses. The stars are what paint the sky with light and are made of various chemical compositions, shapes, and sizes. After some thought we settled on soda bottle rockets, like those found in Make Volume 05, to be our delivery device. The rockets have everything we need to deliver the LED stars into the night sky.
The container is the 2-liter soda bottle. The lifting charge is the compressed air and water. The LEDs are the stars and fuses. The charge that disperses the stars is usually black powder – it is what makes the big boom before the stars light. We are not using black powder so our charge is going to be gravity and the wind. What about the boom? If you have launched soda bottle rockets before you know that when they release they make a big boom on launch. We have all the elements of a successful firework: loud noise, pretty lights, and the element of surprise.
During our experiments we created the LED Chutie, which we brought with us to the 2013 World Maker Faire in New York City. The LED Chutie is an aerial version of the LED Throwie. The Chutie uses a plastic bag for a parachute, a LED, and a 3-volt coin-cell battery. If you can not get outside for fireworks, the Chutie is perfect for indoor fun too.
The Chutie is the basis for the stars in our firework. By combing the Chuties with ping pong balls, plastic practice golf balls, balloons, and straws we can make a wide array of effects in the sky. Just remember that everything that goes up must come down which means that your stars should be light and not a threat if it were to fall on someone or something. The stars with parachutes fall the slowest and spread out the widest from the rocket. The ping pong balls and the plastic golf balls travel higher and fall faster. If you are over asphalt or concrete the ping pong balls make fun sounds when they hit the ground.
We need to use a launcher for our rockets. The one I use is a combination of the one from the MAKE Soda Bottle Project and the release mechanism from this launcher on Instructables. Before you try all this at night, I suggest you test during the day to be sure you are comfortable how everything works and how your rockets behave. Besides, its another excuse to do more launches. Keep safety always and first in mind. These fireworks may be filled with water instead of fire but they still pack a lot of energy. During tests our launch crew decided to put on helmets for safety (but mostly for fun).
We hope you have a lot of fun with your Soda Bottle LED Fireworks. We are hooked. We already have plans for other forms of LED Fireworks. Keep in touch and check us out at SolderingSunday.com. If Make let’s us and we are ready maybe we will have a “Firework” display at the 2014 World Maker Faire in New York. We just need to build that Raspberry Pi launch controller we have been thinking about.