I'm gonna be honest with you guys, I'm 24 years old and I still need a night light sometimes. I've had plenty of time to look into all sorts of lights, be it motion-controlled, light-sensitive, changeable brightness, etc., but none have had the charm or usefulness to suit my tastes. None of them are also portable or half as stylish as this, and so I present The Star Jar!
The Star Jar initially started as a glowy mason jar that I charged with regular light or a small blacklight. It was cute, but the glow effect didn't last very long, and the blacklight stuck out the top of the jar a good few inches. Not practical in the least. So I think, "Why not add a UV LED to the top of the jar?" Being a broke college kid made that part more difficult than I would've liked.
Ultimately, the parts used were:
For the circuit-
- 1 UV LED
- 1 resistor (these came with the LEDs, but the colors on them are pretty wonky. You might not need this.)
- 9-volt battery clip
- 9-volt battery
- 1 small switch (I used a tiny SPST switch from Radio Shack, use whatever switch/button you'd like however)
- Soldering iron and solder
- Some electrical tape to cover the exposed parts
- Duct tape to hold the battery in place
For the jar-
- 1 mason jar (whichever size suits you)
- Several different colors glow-in-the-dark paint
- Something to dot the inside of the jar with (I used a broken mechanical pencil)
- A lid for the jar (preferably the kind that come in two pieces)
All of these parts I had laying around except for the switch. The LEDs came from a friend who bought the wrong kind and the electronic parts were mostly gutted from some useless walkie-talkies.
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Step 1: Painting Your Jar
The first thing you'll need to make a Star Jar is the jar. Find one you like, and one that'll look good with whatever you're using it for, be it decoration or personal night-light-y use. I think mine is a quart. You'll also want one with the two-part lid, so you can take the flat part off for making the circuit, but if you can make it work then go for it!
You'll want to assemble a variety of glow colors so the jar isn't one big blob of a color (unless that's what you're going for). Find a utensil like a chopstick or a paintbrush to generously dot the inside of the jar. Wait until it dries. Easy peasy, right? Set the lid aside for the next step in the meantime.
Step 2: Gutting the Walkie-Talkie for Parts and Assembling the Circuit
I knew I needed some sort of battery for my jar, but being broke kinda took all the fun out of shopping for parts online. I found these while cleaning out some boxes and realized I could just recycle these instead of spending money.
Opening the walkies was fairly simple with a standard phillips head screwdriver, but depending on where you get your parts it could be different.
The board had all sorts of neato parts on it. There was a spring-loaded pushbutton, a switch, the squawky parts, a tiny speaker, and the battery clip with a bunch of extra wire. All I used for this project was the clip and wire though. If your walkies/toys have any extra doo-dads that you think would be awesome, go for it!
Next, I prototyped the circuit on a little breadboard my boyfriend had laying around. Before we decided 100% to use the 9-volt clip, we tested the circuit with a variable power source to see how the unknown LED did. It turns out 9 volts was perfect! After double-checking that a 9-volt battery would fit on the underside of a jar lid (it was also perfect!) we moved to assembly.
We taped the battery down and marked where we wanted the switch to go. I drilled a hole in the lid and did a test-fit to make sure the switch would be alright. Then we soldered.
I asked boyfriend to show me how to solder, but he did it all himself. Sorry about the lack of pictures :(
I included a close shot of the final circuit as a sort of diagram since it's not a complicated setup at all. Boyfriend says make sure the resistor is on the positive side of the LED. (Seriously though if you have any questions feel free to ask! I'm still learning though.)
Once the circuit is soldered together, all that's left is to test it and attach it to the lid. I used some spare duct tape to make a tube (tape on the inside and outside) so the battery can be changed easily. Attach the battery tube to the lid to hold the battery in place, then attach the switch to the pre-drilled hole, then drop the lid onto the jar and screw on. Viola! You made a Star Jar!
Step 3: Turn It on and Impress Everyone!
Go ahead, you know you want to try it. Flip the switch and watch your jar light up! Go hide in a dark room and try it too! The best part is the glow paint will continue glowing for a bit after you turn the jar off, depending on how much paint you used at first. The best part about this is that if you get bored of the pattern in the jar, you don't have to make the whole thing over again! Paint another jar and just swap lids, or keep several jars around for different occasions! Change the LED to a different color and frost the glass instead and make a cute lantern! The possibilities are endless, so get started!