Making Fireflies

In busy times, it takes a certain combination of inspiration, spare time and a little cash to stop dreaming and start making.  I was inspired to make a cheap solar light back in June based on an Instructables post involving deconstructing solar garden lights and reinstalling them in mason jars.  My inspiration held out long enough to search fruitlessly for some cheap solar lights but not long enough to make anything.

Fortunately for me, Evil Mad Scientist attacked the concept again recently, further reducing the time and money required to get something made.  Inspired again, I picked up 12 CR2032 3v batteries and a bag of 25 diffused 5mm yellow LEDs at my local electronics store.  A twenty-five cent roll of tape from the bargain bin completed my purchases.  Total cost was under $20. One firefly was about $1.50.

I made the first firefly at a stoplight on the way home.  Unwrap the battery, slide one leg (lead) of the LED onto each side of the battery and you have a firefly.  A little tape around the battery covering both leads keeps it lit. If it won’t light up, flip the LED around for a quick polarity lesson. The longer leg is the positive anode.

At my house, proper presentation is the key to early adoption.  You can’t be too excited about a new project or they’ll go back to the couch.  Casually toss a lit firefly on the table and instruct them to stay out of your bag and they’ll have ten of them glowing before dinner’s ready.

True to their nature as little makers, they started testing multiple LEDs on the same battery.  Luck (and some bent LED leads) taught them about switching the power on and off.  We put one firefly in an empty widemouth drink bottle and made a garden lamp, no glass jars required.

This project was painfully simple, requiring absolutely no skill and little cash.  It was fun to see the boys light up their fireflies and run around in the dark.  Inspiration, time and cash all came together.

LED’s, Fireflies, Li-ion Battery

(Grab some multi-LED’s and switch the polarity, they’ll switch colors)

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