Fiber Optic and LED Minature Garden Light





Introduction: Fiber Optic and LED Minature Garden Light

About: Always making something....

This project uses LEDs and fiber optics to light up a tiny garden full of flowers, leaves and grass. The box is built from acrylic sheet, it runs on a 9 volt battery and has a sliding door on the bottom for easy battery access.

I've been collecting up little plastic flower beads for a long time. The matte finish has a bit of a glow to it in ordinary daylight so I thought they would be perfect lit up. The fiber optic cable was a semi impulse buy (I've wanted to play with fiber optic since I was a little kid and my parents got me one of those glowing flashlights that were more effective at poking eyes out than anything.) The electronics are easy to get at any Radio Shack (though ordering them in is much, much cheaper) and the rest of it can be rounded up with a trip to the craft store.

I'm really proud of the way the battery access is set up. I've been working on a way to do that for a long time. The wiring is all wrapped in shrink tubing.

The finished light has a 3 by 3 inch base, and looks great on a bookshelf (where mine is) and would be fantastic in a little girl princess room as a nightlight.

Step 1: Materials and Tools List


- about 6 by 12 inches of 1/16 inch thick clear acrylic sheet
- black spraypaint
- 1 minute epoxy (be sure it's a plastic and metal friendly version)
- a switch - anything small enough to fit on a side wall
- a 9 volt battery
- a 9 volt battery snap
- 14 3mm LEDs - I used white
- a resistor appropriate to the LEDs you're using - this site is super helpful:
- a few feet of 1/16 inch black shrink tubing (in the electrical department if you've never used it)
- around a foot of 1/8 inch clear plastic shrink tubing
- about a foot of 12 strand plastic fiber optic
- 24 gauge wire (mine is craft wire from wal-mart, use whatever you like)
- plastic flowers and leaves - I used about 35 flowers and 50 leaves
- plastic lacing in various greens and yellows - this is what 'lanyards' are made of, you know, the classic summer camp craft stuff


- heat gun
- needle nose pliers and wire cutters
- something to drill holes and something to drill into (to protect your workspace)
- something to cut acrylic sheet - this is thin, so an 'acrylic cutter' that scores and snaps will work - I use a dremel to drill holes and cut the hole for the switch
- masking tape

Step 2: Cut the Acrylic Sheet

I included a file with the appropriate pieces. Cut down your sheet of acrylic to the sizes listed, then spray paint one side of each. I didn't paint the piece everything attaches to, but you can if you want. The painted side of the sheets needs to be the INSIDE of the box.

Step 3: Make the Flower Stems

Cut a chunk of the fiber optic cable - 3 to 4 inches, and pull the strands out of the tube.

Place a small pieces of masking tape over the back of each flower.

Use a pin or piece of wire to poke a tiny hole through the tape that goes through the center of the flower.

Push the fiber optic cable end just through the hole.

Put a drop of the 1 minute epoxy into the center of the flower to hold the cable in place.

When it's hardened (around 10 minutes or so) peel off the tape.

Do this to all of the flowers you plan to use.

Step 4: Make the Leaf Stems

Cut a 5 or 6 inch piece of wire.

Fold it in half.

Thread a leaf onto it.

Give it a twist or two to hold it together.

Thread on a short piece of shrink tubing and shrink it.

Keep adding leaves and tubing this way until you like it. Leave plenty of un-leaved wire at the end, but finish it all in shrink tubing.

Make enough of these so that there is one leaf stem for every 2 to 3 flowers.

Step 5: Attach the Flowers and Leaves to LEDs

Group a couple flowers (3 worked the best for me) and one flower stem.

Arrange them together so that the heights look good to you.

Cut them all off evenly.

Thread them into the clear shrink tubing a bit. The goal is to find a length of tube that supports them and lets them move around a bit.

Cut the clear tube off with about 1/4 to 3/8 inch extra.

Push the bulb of an LED into the end of the tube. Fidget with it until the LED is solidly in the tube and the fiber optic cables touch it.

Heat shrink it together. BE CAREFUL. The fiber optic is a thermoplastic and will melt with heat. Try to move the heat gun around as much as possible and focus the heat toward the bottom.

Repeat this until all of your flowers and leaves are used up. I ended up with 10 groups.

Step 6: Make the Grass

Cut lengths of the lanyard plastic that are around 4 inches long.

Group them in 4 to 7 strand bundles.

Use a short piece of wire to twist them together. This wire will push through the base to support the grass.

Wrap another piece of wire around the whole group folded in half to keep the strands upright (look at the pictures - it's easier to see than to explain).

Repeat this until you have about 24 groups.

Step 7: Glue Up the Acrylic Box

You have 4 pairs of plastic pieces for the wall of the box. A pair is one large piece, and one that is shorter and slightly narrower. Glue them so that they are centered horizontally and line up at the bottom. The epoxy works well for this. You want the masked side out - glue the painted sides together.

When they're set up you'll need to cut a hole in one pair for the switch. Mark it out - close to the bottom, not too close the the end of the piece. Drill the corners of the switch then cut between them (I used a dremel with cutting wheels and bits.)

This is a time to really, really use your safety glasses. Plastic sends small sharp pieces flying around when it's drilled or cut this way. You only have 2 eyes, and even if you only blind one of them you're going to have a hard time not running into things.

Two sets are longer and two sets are shorter. This is so that they fit up to make a proper box. You need to glue them together with the epoxy. Tape them together while it sets up, and tape it all to the square ring to be sure it sets up nice and square (again with the pictures - visuals make more sense here.)

The square 'ring' and two 'U shaped' pieces form the bottom. Glue the narrow 'U' onto the square. Then glue the wider 'U' on top of that. This forms a track for the battery door to run in. The other square piece is a door, and the narrow strip is the handle. Glue the handle to the door.

Once the bottom is set up glue the sides to the bottom. This will form the box, and the panel with the flowers attached will drop into the top.

Step 8: Attaching the Flowers and Grass

On your remaining plastic decide where you'd like the flowers to go. Spread them out as equally as you can. Drill pairs of holes for the LED legs to go though, keeping in mind a 'route' for the wiring. All of the positives need to connect, and all of the negatives need to connect. I added 4 LEDs without flowers to help brighten it up.

Once those are drilled fill in the board with single holes for the grass. Again spread them out, and make sure there's a row of grass around the outside edge to camoflauge any visible LEDs.

Push one LED through the panel. On the bottom fold the wires over in the direction of the next LED you plan to wire.

Cut two lengths of wire long enough to trace the entire patch of the LED wires.

Leaving a short tail, twist one of them around the positive wire of the LED on the panel. Cut a piece of the black shrink tubing long enough to reach from there to the next LED (plus a bit, because it will shrink along the length of the wire as well.) Thread the tube on and shrink it. Do the same to the negative side. Trim off any extra LED wire. Add another LED and keep wiring the same way. Connect up all of your LEDS being REALLY careful to keep all positives connected to positives and negatives connected to negatives.

At the end of the positive wire cut it down to an inch or so, then add shrink tube and a resistor.

Push the grass pieces through their holes, fold over the wire on the back and secure it with a bit more epoxy.

*All images are the BOTTOM of the panel.*

Step 9: Final Wiring

Attach the positive resistor end to one terminal of the switch - add a piece of wire and some shrink tubing to do it.

Connect the other terminal of the switch to the positive side of the battery snap and cover it in shrink tubing.

Connect the negative wire from the panel to the negative wire from the battery snap and cover it in shrink tube.

The shrink tubing ensures that the positive and negative never touch, and it makes for a nice, finished look.

Step 10: Final Step

Drop the panel full of flowers and grass into the top of the box. You'll probably want to glue it into place for security.

Turn it on and put it somewhere awesome.



    • Woodworking Contest

      Woodworking Contest
    • Clocks Contest

      Clocks Contest
    • Planter Challenge

      Planter Challenge

    We have a be nice policy.
    Please be positive and constructive.




    I'd like a whole nocturnal garden of this kind of stuff. Neon lights, uv, glow in the dark, water falls with lights. ;)

    1 reply

    Inside of my head, that looks awesome. lol

    Also, where can I get the flowers and the leaves from? Can you list the kind of LEDs you used and the resistors? If I used a 9v dc wall wart, would I need to use different resistors and other crap? Please help me out. I'd appreciate it a lot. I know very little about electronics. This is going to be just my 3rd project so yeah I still need to gain more experience and knowledge. Thank you!

    11 replies

    The flowers and leaves are from Hobby Lobby - I think Wal-Mart carries similar pieces. Pretty much any craft store should have them. The LEDs were a pretty standard white, 3.3 for forward voltage and 20ma. I used a 150 ohm resistors (I technically cheated this a bit - they came with some other LEDs I ordered and are designed for 12v power, which I guess is used in cars, and I should have used a few resistors but I just used the one. Overall, on a project like this, I'm mostly concerned with it lighting up and looking good, not whether I've technically picked out exactly the right resistor the the situation.) As far as a wall wart goes, 9v is 9v, so you should be able to use the same. The LED calculator website is really where I learned almost everything I know about resistors and such, it's a great resource. This is only a bit better than the blind leading the blind - I'm entirely self taught on electronics, and just sort of play around with things until they work. I figure that with LEDs at about 3 to 4 cents each I can afford to screw around a bit - it's cheaper than almost any other entertainment out there! Let me know if you have any other questions and I'll do my best to answer them. Good luck!

    It actually would depend on the amperage of the wall wart. If it's amperage is the same or at least fairly close to that of a nine volt battery, then you shuld be able to keep things the same, If it's higher, then you'll need to adjust for the power increase, or your system will burn out sooner, if not immediately. 9v really isn't 9v. Volts and amperage make power. look at the difference between between 12v batteries for a good example. An A123 will give you a good buzz to your tongue if you touch both ends, but a car battery can provide a dangerous, if not lethal, shock. Not that I've seen many dangerous 9 volts in my time. Sorry, but I don't know what the amperage rating of the average 9v is, off-hand.


    Sure, volts(amps)=watts. But in reality the amperage is determined by the voltage(resistance). It makes sense if you think about it. If you have a dam with a difference in water levels on either side and so there is a difference in pressure (like voltage). It is how much you open the flood gates (flood gates having a sort of resistance) which produces the speed of the water flow (water current, like electrical current aka amps). If the pressure on the dam is higher the next day, the current will be more though the gates are open the same amount.


    So amps comes from voltage divided by resistance (made a mistake in original post) and is completely dependant on those two. An amp rating on a device is how much it can take before it dies, not how much it produces.

    Ever tried to charge a cell phone with a charger that has different amperage than what it requires? It either confuses the phone into thinking it's charged early, or it likes to heat up the phone until you unplug it or it's trash. I've got a wall wart that converts to a car lighter socket at the end, and I've only found a couple of gadgets that are compatible with it, even though they are rated for 12v from a car battery. Most things fritz out, and one stopped working entirely (it was old), when I tried them with it. Even my dad's tire compressor didn't work with it. Though, I'm not sure what the Amp rating is in a car lighter normally, so can't tell you exact difference. That's really what got me thinking about it. And there is an output amperage on wall warts as well, not just input limit. i.e. my phone charger has an input rating of 0.2A and an output rating of 550mA. Gotta pay attention to that when you pick your chargers, they make a huge difference. Some gadgets aren't as sensitive to a bit of variance, but most don't like to be 'overfed'.


    The polarity of the socket may be important. Most wall warts are negative outside positive inside, but not always. The input refers to what kind of plug it was designed to plug into. The output refers to how much it can supply before it becomes damaged. If you plug in something to a power source that has the right voltage output, right polarity, and right waveform (ac/dc), it should work as long as it can supply enough current. If you try to pull too much current through a wall wart for too long, you can damage it and cause it to behave incorrectly.

    Yes, but car lighter sockets are fairly universal at least in polarity of the socket, IIRC. That's why I used it as my example. When you get down to it, amperage kills electronics a lot faster than voltage Like people. O.O


    Maybe it was just a faulty socket. In general, you are right about amperage, but amperage aka current can't exist without voltage aka pressure existing to push it.

    Perhaps. Still charges my DS fine, so I'm not likely to toss it anytime soon though. lol I know how amperage works. My point was that 9v at 5 amps is not the same thing as 9v at 10 amps. A camera battery is twelve volts and will only buzz you a bit, but a car battery can kill. Still, you might be right about the socket on my charger. Hadn't really thought too much about it, since it actually works for the device I bought it for.

    Nice job! One thing to watch out for is the actual transformer voltage. When using a light load such as a few LEDs the actual voltage may be much higher than stated. I have seen some 9 volt transformers have a voltage of 13 volts until a significant load was placed on them.

    If you are looking for a small number of LEDs with cheap shipping ($3.00 shipping to anywhere in North America) have a look at our LED store.

    Hi. Thanks for replying quickly. I already ordered the parts from eBay. Great instructable and thank you for the help!

    This is a very eye catching piece. Could double as a nightlight :)

    I've found all my LEDs for other projects on eBay. There are tons of choices at good prices. Here are my search results if anyone is interested.
    3mm LEDs

    1 reply

    Thanks! Yeah, I get all of my LEDs from eBay because I pretty much get stuff then come up with projects. It's nice to have a ton of parts around for doing that kind of thing.

    is there a way that i can get fiber optic wire from every day stuff example: open up a ethernet cable

    1 reply

    I have no idea - but when I was checking into supplies the 'fiber optic lighting' cable I found was way cheaper than ethernet cord so I didn't really investigate any further!

    This is very creative! I Love it! 5 stars!

    Very cool project, Techno.