Do It Yourself: LED Throwies

LED throwies are simple home made illumination devices using a LED, a battery, some duct tape and a magnet. They were created mainly as a way to do urban graffiti but can also be used as simple illumination devices, trail lights and markers.

The basic throwie model requires a 10mm LED (red pictured but other colors can be used), a 2032 coin cell battery (very common and easy to get), some duct tape and a magnet, neodynium magnets recommended.

The construction is simple just make the LED legs contact the positive and negative sides of the 2032 battery, since a LED is a diode this will only work in one position. Stick the magnet to the positive side of the 2032 battery and wrap with ducttape. To use it just stick it to a metallic surface and voila!.

Runtime for a simple throwie can be several days, with a red LED one week of runtime is normal depending on the LED used and the quality of the battery. If you want to use the throwie as a marker or locator you can use a small piece of paper to prevent the contact between the battery and the LED and remove the tab when you want to use it.

Variations include the use of a photocell to turn on or off the LED based on ambient light extending runtime, adding a simple switch, use of 3mm or 5mm LED and smaller batteries to make it even smaller etc etc.

For the ones that like minimalistic EDC you can always have one ready in your kit with a tab to prevent activation and use it when you need it, they are easy to do, can be made by children, fun to use and economic.

If you want even more information you can read this article at Instructables.com