Solar Geode City

thingiverse

This is a solar lighting source for Sirofsky's beautiful Geode City. The example LED holder file, pictured, is a bit rough but functional only. Five-millimeter diameter LEDs are used with space on the back for wiring and held in place by hot glue. Originally, rope/string lights were used, but they didn't direct enough light outward, so three LEDs were added to improve lighting. Clear or translucent filament should be used as it provides a better viewing experience. The interior white/translucent city piece is printed with Solutech Glow in the Dark, which doesn't glow much; however, a previous attempt with translucent PETG green blocked too much light. Any fairly clear or white translucent filament can work well. Links and samples are provided for reference only, and you may find better alternatives. A similar solar string light system is used elsewhere, but it has 100 bulbs compared to the current 50. To determine the correct resistor value, confirm the voltage coming out of the solar panel, which was about 10 volts in this case. Use a resistor calculator or formula, such as the one provided by LED Center, with information on voltage and current to find the right resistance. Three yellow five-millimeter LEDs were used, each with a two-point-one-volt forward voltage, and a common current of twenty milliamperes was assumed unless otherwise noted. A 220-ohm resistor was calculated to work well in this setup. Be sure to mark and identify the positive and negative wires on the resistor. The long leg on the resistor is the positive side, and it can be oriented either way. Hot glue was used to secure wiring and mounting in place. Hopefully, this information will make building a solar lighting source for Geode City an easy and rewarding experience.