Instructables
Picture of Candied LEDs
A fun experiment combining simple electronics and common food stuffs. You'll need 4 cups of sugar, 2 cups of water, wire, electrical tape, assorted LEDs, paper cups, wax paper, a stove and a medium sized pot!
 
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Step 1: Preparing the Sugar Syrup

Picture of Preparing the Sugar Syrup
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Boil the 2 cups of water in the medium sized pot, adding the sugar 1 cup at a time and waiting for it to dissolve. It's important to keep stirring the pot and not to let the sugar cook too much or it will burn.

Step 2: Wrapping the LEDs

Picture of Wrapping the LEDs
Take the LEDs, wire and electrical tape and wrap the wire around the leads, securing them with the tape. Wet the heads of the LEDs slightly and roll them in sugar to coat them and provide a base for the crystals to grow.

Step 3: Pouring the Syrup

Picture of Pouring the Syrup
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After turning the sugar syrup off wait 5-10 minutes for it to cool, then pour it into either glass jars or paper cups. My first attempt was with glass jars but I found the crystallization took too long so I transfered the mixture to individual paper cups and that made it much easier. Wrap the ends of the wire around a pencil and lower it into the cups, adjusting the wire wraps to the height of the sugar line so that the head of the LED is totally immersed in the sugar.

Step 4: Unwrapping the Crystals

Picture of Unwrapping the Crystals
Set aside in a cool place away from direct light and wait 1-4 weeks, depending on how large you want the crystals to be. Peel off the paper cup from the sugar crystal and carefully break off the unconnected crystals from the main crystal formation around the head. Running it under warm water helps.

Step 5: Dry and Test

Picture of Dry and Test
Set on a sheet of wax paper and allow to dry for a day or so. After completely dry, test with a 3V coin cell battery. You'll notice that the sugar helps diffuse and extend the luminosity of the LED to a much larger area. 

Step 6: Play!

Picture of Play!
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I'd advise you not to eat this experiment- LEDs are small enough to be accidentally swallowed so use caution if you do this experiment with kids. Have fun!
Paulus442 months ago

What if you put the LEDs in a clear drinking straw before dipping in the sugar. Then you can use it maybe as a candy. Anyway great idea. Thanks

That's certainly a first.

kcvrokz1 year ago
this is great..
emdaniels (author)  kcvrokz10 months ago
Thanks!
spiderstones10 months ago
what kind of battery did it take?...nice job!
emdaniels (author)  spiderstones10 months ago
Thanks! A 3V coin cell battery works well.
nice job, will these rot go get sticky if i for say left them in my pocket
emdaniels (author)  The_HandyMan1 year ago
Most likely- it's sugar so if they are exposed to moisture and heat they'll melt a bit.
LED Lollipop?
ledsign2 years ago
It's very cool!
Thanks!
well done for winning the ipad 2!!!!!!!1
:)
emdaniels (author)  harry potter rules2 years ago
Thanks!
tato3123 years ago
wow, those look cool, you have my vote! :D
emdaniels (author)  tato3122 years ago
Thanks tato312!
mrdz vela3 years ago
You got mine too, I can't wait to try it myself. Thank you!
emdaniels (author)  mrdz vela2 years ago
Thanks mrdz vela!
bakesalot2 years ago
I've made rock candies but never thought to do them on lights! Really like this idea (:
emdaniels (author)  bakesalot2 years ago
Thanks! :)
Kaisei133 years ago
It defiantly wouldn't be edible, but I wonder if this would work with borax crystals?
emdaniels (author)  Kaisei133 years ago
Yes I think so- you could probably make one with epson salts too.
:O I want to make candied throwies for Halloween!
Gizah3 years ago
I really like the way they look, is there any way of conserving them to use them in an actual project? I mean, I guess they do get old and ugly eventually? Anyways, awesome instructable
emdaniels (author)  Gizah3 years ago
Rock candy typically lasts anywhere from 8-24 months depending on humidity, temperature and packaging. If you are not planning to eat it I'm sure the shelf life is for as long as you can keep it away from water and high temperatures. It's sugar in it's purest form, so barring any food coloring that would most likely fade over time, the crystals should stay clear.
scoochmaroo3 years ago
This is amazing. I want to eat them.
emdaniels (author)  scoochmaroo3 years ago
Thank you scoochmaroo! They are probably fine to eat if you can get lead-free LEDs.
excaza3 years ago
This takes over the spot in my heart previously stolen by LED throwies. This is definitely the most creative use of LEDs I've ever seen!
emdaniels (author)  excaza3 years ago
Thanks excaza!