LED Microcontrolled Stained Glass Firefly Pendant





Introduction: LED Microcontrolled Stained Glass Firefly Pendant

This Instructable will walk you through the steps needed to make a stained glass pendant with anLED that blinks in a pattern using a microcontroller.

The blink pattern is an actual firefly song of a type of Japanese firefly. It is a scaled down version of the Jar of Fireflies code that my partner wrote. I have included the code here.

Step 1: What You Need

art glass (from a glass supply store)
copper tape (from a glass supply store)
a glass cutter (from a glass supply store)
pliers (glass pliers are best but you can substitute regular pliers and coat the tips with rubber like the ones below)
soldering iron
soda can

tiny wires, preferably two different colors
ATTiny45 chip (code attached*) (Digikey #ATTiny45v-10SU-ND)
LED (Digikey #160-1423-1-ND)
tiny switch
CR2016-1F2 battery (Digikey #P222-ND) (Really, any 3v battery will do. This one was chosen for form factor.

*Getting the code on the chip could be its own Instructable. When I am a microcontroller guru someday I will post on how to do that.

Step 2: Score & Cut the Glass

The first thing you need to do is decide the size of pendant you want. I made mine *just* big enough to fit everything on the back. This is mostly dictated by the size of the battery.

Art glass is a bit softer than window glass. It is much easier to cut as well. Draw your lines on the glass. Dab a little mineral oil on the cutting wheel to keep it moving nice and smoothly. Apply slight and even pressure and roll all the way to the other side of the glass (past your markings).

Glass pliers are very nice and specifically designed to break your glass along your score. They're kind of rounded on the ends and have rubber pads to protect the glass from scratching. The pliers below are regular pliers that have been dipped in liquid rubber several times to get the same effect - mostly anyway. Either way, they will break the glass *way* better than your hand.

Score and break until you have a square.

Step 3: Prepare Picture

Cut your soda can and vellum to size. Your picture and glass should already be to size.

Cut a hole in your picture and your aluminum that the LED can shine through.

There will be four layers for your picture before we start on the electronics. Stack layers in the following order:


As you can see, we're using the vellum to diffuse the LED light.

Copper tape is not difficult to work with. Line the edges first. Squish two opposite sides down flat. Run your fingernail or other flat surface over them to make the edges sharp. Then squish the other two sides taking care to make nice corners. The flatter your fold against the glass the nicer your solder will look when you're finished.

Step 4: Solder the Edges

Using a syringe and/or paintbrush apply flux to all of the copper surfaces. It's pretty difficult to get too much on there. Don't worry about getting it on the glass. We can clean it up later.

Use your 80 gigawatt soldering iron to solder around the edges. If you've never used a stained glass soldering iron before get ready for a treat. They're loads of fun. They heat to around 800 degrees F so don't get them anywhere near electronics or you'll fry everything. That's why we're doing this beforehand.

Bend a thin wire around a paintbrush to form a jump ring. This will give you somewhere to hang your pendant.

Step 5: Solder Electronics

These components are beyond tiny. That's what makes them so cool! But you are going to be a soldering ninja after this so hang in there!

The LED is probably the most difficult to solder. It is quite handy to stick it to some double sided tape before you begin. You want to have more than one handy just in case. They're invisible if you drop them!

I have marked Pin 1 on the back of my chip with a white dot. You can also tell by the printing on the back and dot on the front. You may need to cut the soldering leads on the battery and the switch to fit. I recommend you wait until everything is soldered before trimming though. Solder everything per the schematic and glue down the chip & switch.



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    Where did you get your switch?  Digikey?  If you did, could you give me the product code.

    A company named Canfield makes a great lead free solder. Most stained glass stores have it or can order for you. Try delphi.com.....by the way, it isn't made from silver.

    Hey I'm just getting started with micro-controllers and just got my Arduino learning kit. I was wondering how you physically interface the micro-controller with your computer to get the code in? Must be some USB micro-controller or something can you help me out? Cheers!

    Where do you get your silver solder? I am having a hard time finding it in a stain glass shop. Weird. Awesome project! I have been trying to put together something similar, I am using the regular lead mix solder for ornament type pieces, with pictures on both sides.

    1 reply

    Most of the stain glass stores have a lead mix solder but you should be able to find a lead free version in any electronics store.

    Where can one find an "80 gigawatt" soldering iron? Something Doc Brown has in the delorean maybe? ;D Might wanna fix that

    2 replies

    Oh sorry! You're absolutely correct. It should have been "jigawatt".

    1.5 jiggawatts? WHAT'S A JIGGAWATT?!?!

    beautiful.... simply beautiful.... I think this could work with a valentines day pendant too. I would make one for my girlfriend.

    Very nice project, I work with silver and gold when I'm doing jewlery and adding the glass with a nice gold trim and siver backing would set it off very nice. Do you have the program that you could post for those of us that know how to burn a chip. I could program it my self but I like the way it operates as is. I will do this instructable but just replacing the siver solder trim with a 14K gold outline and enclosing the back with sterling silver with a hinge so it will open like a book to hide the electronics for a finnished looking project. Also I would change from a picture to a stained glass using opque colors so the electronics wont show through the glass. One other note: I was supprised that you did not include a diode to protect the chip just incase some one installed the battery backwards. The diode would protect this kind of thing and a resistor to the LED to control the current so the battery would last longer and protect the chip from over heating. I know yur just using a 3v battery but you never know with MCUs what could happen. I think this project is well deserving to include it into the book contest so please enter it and You'll get my vote for it. Great Job!

    2 replies

    Hi! Thanks for your reply. I'd love to se this done in silver & gold. It would be lovely! I just moved from solder to silver myself. The code is actually posted on this page. The name is firefly_pendant.tgz. I think a hinged back would really finish the project. Good luck! I don't think the piece is really finished enough to be included in the book. But thanks for the compliment regardless. :)

    clamoring, of course this instructable would be great for the book even if you don't have the back on it. It will inspire people to make it a little diffrent. I still say go for it so I can vote for you. I'll post my finnished pendent when I get it done i'll post a pic here on your comments. Jax

    Honestly, I'd just remove that switch (it can't be very comfy) and just solder a thin plate to the red lead coming from the IC. That way you could just shimmy it under the battery guard. If you wanted to go a little further you could also make the frame a bit deeper and embed the battery and the IC (since they seem to be the same height) inside the unit. Would make a better presentation. Just my 0.02$ -J Also, do you know of any good howto's on flashing that program. I was actually going to try this instructable. :)

    Neat. Smart. Awesome. Really cool. +1 rating. I like it A LOT. Wish I could try this out.

    6 replies

    You can do eet! I believe in you!

    This is most likely way to hard for me. :P I'm only 13!

    Don't let that stop you. Your instructables are very good! Part of being a member of a community is asking for help when you need it. Otherwise what are you here for? What part are you stuck on?

    Thanks! Right now in the Share the Love contest, I'm in 6th place for the ratings on my LED one... wishing I could get 1st for a T-Shirt. Anyways. Well, I haven't attempted this yet, but I might, and I know I'll get stuck on the soldering. I'm okay at it, but not with small objects, I will probably drop a chip and lose it, or totally destroy it. It's really cool though.

    Two tips for soldering tiny components: use double-sided tape, and don't hold the soldering iron on for long... use more of a brushing stroke. Oh, and buy a very tiny tip. The standard tip is too big for something like this.