In this tutorial Bare Conductive
will show you how to make a light-up greeting cards with LEDs! To do this we will use some Bare Paint, a battery and some standard, flashing and surface-mount LEDs.
To help you complete this project we've made all the components available in a Kit which you can buy at our online shop. Just select the Greeting Card Kit
. Alternatively you can source the necessary components yourself through Farnell or Digi-Key!
Step 1: What You Will Need
Bare Paint or Bare Paint Pen
A4 Coloured Paper - You can download the templates HERE
Scissors / Craft Knife
Cutting Mat (if using knife)
- We've included the links to where you can buy some of the components in case you want to purchase them individually
Standard LEDs - Digi-Key
3V Coin Cell Battery - Digi-Key
Step 2: STEP 1. Download and Print your Templates
In this tutorial we will show you how to paint a circuit with either a brush or a Bare Paint Pen. We will be making the blinking robot card and the mother's day card but you can use these instructions to make lots of other card designs too - download the PDF for the Robot cards below.
Step 3: STEP 2. Make card body
Print your template onto coloured piece A4 paper. Cut along the cutting lines and fold along the folding lines. Keep cut off bits for later. If you are a little person please be careful and ask a parent or teacher to help you with the cutting.
Step 4: STEP 3. Paint your circuit
Using a paint brush, carefully trace around the printed black line on the template with Bare Paint. Make sure your line is fairly thick and a consistant width (about 3mm).
Or… if you have a Bare Paint pen you can trace around the circuit with your pen.
Step 5: STEP 4. Applying components (POLARITY)
Open up your card and have a look at the circuit key at the top - notice the little symbols with the plus and minus signs - these show you where your components go. Batteries and LEDs are polarised which means you have to put them into your circuit the right way round for electricity to flow. This little map is going to help you do that. The only thing you have to remember is that the long leg of the battery we're using is positive and the long leg of the standard LED is also positive. (We'll talk about surface mount LEDs later). If you're making a robot card you can also use flashing LEDs to bring your robot come to life. Lay out your components on the componeny key so that the long leg is on the positive side and the short leg is on the negative side. Now splay out the legs of the battery with the pliers and the LED. Snip the legs of the LED to within 3 mm of the lamp. Don't forget which was the positive - mark it with a permanent pen to help you remember.
Now if you are using surface mount LEDs it's a little more complicated. The surface mount LEDs we are using have four legs. Two legs are positive and two legs are negative. Pick one up and have a good close look at it. You will notice that there is a little dent on one side - this side is the positive side. For a closer look at these LEDs check out our Circuit Basics tutorial (coming soon). Lay out your components on the circuit key so that the positive legs are on the positive sides. We're now ready to start glueing components in!
Step 6: STEP 4a. Attaching the Components
Now take a look at the template and note the gaps where the components go. If you are using a paintbrush put a nice blog of paint either side of the gaps for the LED and battery. Carefully position the components into the gaps, pushing the legs into the blobs and making sure they are the right way around according to the map. Then put another blog of paint on top of each leg to make them secure. Make sure the paint doesn't join underneath the component otherwise you will have short-circuited it - the current would much rather go through that than your component!
Step 7: STEP 4b. Attaching the Components
Applying surface mount LEDs is a bit more tricky. Make a couple of long blobs either side of the gap using your brush or pen either - the positive legs are going to sit on one side and the negative legs on the other - check your diagram and LED closely to make sure you put it in the right way around. Really important to make sure the paint doesn't connect underneath otherwise it will short circuit. If you make your blobs too big and they splurges togther try scrapping of the paint off with a craft knife and try again.
If you're making a card like the Mama mother's day design which has a hidden battery then you don't want to glue it in yet - in a minute we're going to make a little pocket that combines a battery-holder switch!
Step 8: STEP 5a. Making a toggle switch
Switches are useful if you don't want your card to be on all the time (and especially if you want to post it to someone). This switch is just a simple flap of paper, painted with Bare Paint to bridge a gap in the circuit.
Find that little bit of card that you cut off at the beginning. Cut about a third off. Discard the big bit and fold the small bit in half. Position and stick one side down so that it can flap back and forth on top of the circuit break - it needs to completely cover the gap.
Next we're going to paint it with a patch of Bare Paint so that when it closes, it makes a bridge across the gap and turns the circuit on!
Step 9: STEP 5b. Making a battery-holder switch
This switch is useful when you want to hide or cover the battery. Here we're going to show you how to make a paper battery holder that doubles as a switch:
Cut a piece of paper 68mm long by 25mm wide using scissors or a craft knife. If you are a small person then please do ask an adult to do this bit for you. Divide the strip into 4 sections with a pencil, as shown. Make two slits in the middle of one section as shown with the knife - and push the battery through with the postive leg (long) at the top and the negative leg (short) at the bottom, as shown. Flip it over and bend apart the legs using the edge of the pliers. Then turn it back over again and position as shown.
Fold in half lengthways and again, as shown. Unfold completely and glue left end. Fold over once and stick.
Using a brush or pen make two nice big blogs on top of the flattened battery legs - these contacts will bridge the gap in the circuit, effectively connecting the battery which will turn the circuit on!
Step 10: STEP 6. Let it dry and put finishing touches
If you want to get more creative you can add a few more lines and squiggles to your graphic. Just make sure you don't connect to the existing circuit otherwise your might divert the current and make a short-circuit!
If you've made a battery-holder switch glue the switch in as show inside the card. Position the flap so that the big blobs make contact with the small blobs when folded over - this connects the battery into the circuit and turns the LEDs on!
Step 11: STEP 7. Test your circuit!
Close your switch - tada!
For any suggestions or help get in touch with us at firstname.lastname@example.org - and send us your own designs so we can post them on our community page!
Step 12: Troubleshooting
If your LED doesn't come on don't fret, there's a few things you can try -
1. Is your paint completely dry? If not leave it overnight or put in a warm place.
2. Are your components short circuited - is the paint joined up underneath it? If it is take out the component and remove the paint with a knife then re-apply.
3. Is you component in the right way round? Check your componeny key to make sure you have the polarity correct.
4. Are your lines too thin enough or broken? Your lines may be too resistant to pass sufficient current - try making wider or thicker lines.
5. Are your switch contacts in right place, are they actually bridging the gap in the circuit when you close the switch? You may need to reposition them.