Picture of Easy LED Color Changing
This is a simple color changing light that is great for kids and adults. Looks beautiful in a dimly lit room, great for the holidays, and makes a pretty cool night light.
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Step 1: Materials

Picture of Materials
Glue Gun - We are using a low temperature glue gun. It hurts when the glue touches your skin but it does not burn your skin

3V Battery

Film Canister - With inside closing lid (Fuji style)


Two Magnets - One must have a hole in it and not be bigger then the battery. The other magnet must be small enough to fit into the lid of the film canister

All these parts can be bought off of e-bay. We will be selling kits at Cat's Science Club if interested.

Step 2: Make the "Candle"

Picture of Make the
Take your LED and bend the longer (positive) leg at a 90 degree angle.

Insert the short (negative) leg through the hole of the magnet.

Bend the short leg up and around the magnet as shown.

Add the battery negative (-) side facing the magnet and LED.

Bend the longer leg around the outside of battery as shown.

We like to bend the positive leg around so that it is not touching the battery. There is a bit of a spring in the wire. In this way, when we set the "candle" on to the base the pull of the magnets forces the leg to touch the battery, causing the light to go on.

Hot glue around the bulb of the LED.

Move battery around to adjust as needed.

lokerin7 months ago

How long will the battery last?

Cats Science Club (author)  lokerin6 months ago

The battery life varies. We have had them last just over a week when on constantly. They will last much longer if you only have them on when you are using them.

tzq33tdq7 months ago
I think it would be a good idea to specify a colour changing RGB LED because some people may think you are talking about a 4-pin RGB (which are more common). Also, great instructable!
SparkySolar8 months ago

That looks really neat

billbillt9 months ago

Here is a short vid of me lighting up a slow change RGB with nothing more than a 3V button cell....

100_1786.MOV(516x387) 14 KB
iqu12 months ago

but why does it change color? is the voltage changing? or is it because the self induced magnetic field (due to the current flow) interacting with the voltage?

billbillt iqu9 months ago

The led has a chip built into it that controls the color change.... You have to do nothing but be sure the polarity and voltage is correct... All the rest is automatic... Just be sure you get a SLOW CHANGE led... A fast change one will drive you crazy like police car flashing lights...

junits15 iqu11 months ago

i think you have to use a color changing led

I think I have to try this!
Cats Science Club (author)  Hardwired221 year ago

Have you tried it yet? Pretty easy. We have had fourth graders build them :-) and they had very little trouble.

I saw on cat's science club's Facebook page the video of these. Very very cool!!!!

Glad you liked it!

MorpheusPA1 year ago
This is incredibly clever and the old canisters I had lying around are about to get turned into cute stocking stuffers! Thanks so much for the idea.
Cats Science Club (author)  MorpheusPA1 year ago
Made 52 of these in a few hours or less. I was playing with my phone too. ;-)

How did yours turn out?
Very cool. I love the changing colors.
Thanks! It looks even better then the pics can show.