Tiki torches are a fun summer lighting solution. Although fire is generally very entertaining, there are times when a more subdued form of illumination is called for. If it can change colors like this red-green-blue (RGB) “torch,” even better!
Adafruit engineer Tony DiCola decided to make this as a “way to use RGB LEDs that could animate and pulse with different colors, yet be weatherproof enough that they could stay outside for a while.” An upside-down mason jar fit the bill perfectly and was the right size to fit into a tiki torch housing.
To make this display, part of a NeoPixel LED strip is used to provide lighting, and depending on the size of your jar, between six and ten individual LEDs seem to work well. Conveniently, these strips can be cut to size and resoldered, so if you have a longer strip, it can be separated into the material for several lights.
The brains of this operation is an Arduino Gemma board, which can be programmed using the latest Arduino PC software. It comes in a convenient package and at a low price point that makes it great for simple projects like this. Optionally, you can implement an infrared remote control in this project if you feel the need.
The LED light is diffused using clear plastic beads, which can be found as “vase filler material.” Another diffuser option would be to sand-blast the inside of the jar, and DiCola also mentioned that etching cream rubbed on the inside could also work. Though, he would recommend still using the beads as they keep the hardware from moving around too much.
Like many of the projects here, this tiki “torch” is begging to be expanded upon. DiCola mentioned that one could “add a microphone and make the lights sound reactive,” (see this sound-reactive tie project for some idea of where to start) but that a larger microcontroller might be needed since the Gemma is quite limited space-wise. Control from the Web or via bluetooth would also be a possibility, opening up all kinds of possibilities for coordinated lighting!