Hot Glue is cool. You can make lots of fun stuff using Hot Glue. You can make jewelry, you can make box, phone case, make your circuit waterproof and you can use it as Led diffuser. Recently I made a multi-color Egg Lamp using Hot Glue. The lamp has color changing knob and by rotating the knob you can produce many colors. The lamp can be powered from a wall adapter or from any USB power source like power bank or laptop USB port. I think you will like it. You can make it yourself very easily by following the instructions. First, watch my video and if you like it then follow the steps below to make it yourself.
Step 1: Stuffs You Need
Step 2: Preparing the LEDs
RGB LEDs contain red, blue and green LED's. As you can see in the image at right, blue and green combine to produce turquoise, green and red combine to produce yellow, red and blue combine to make violet, red, green and blue combine to make white. There are literally more than produce over 16.7 million different colors!
Many people can't understand or believe that 3 simple colors can make 16.7 million different colors...but it is true. To believe it, you need to understand how colors work. Lets take red for example. On the red scale, there are 256 levels or shades of the color. Red, being a primary color, is key to making those 16.7 million different colors, as are green and blue. All three of those colors have 256 different levels or shades and by varying the shade of the light, you can create the 16.7 million different colors. It's easy when you do the math:
256 X 256 X 256 = 16,777,216.
A RGB LED has 4 pins. Three pins for three colors and one common pin for all three LEDs. Common pin may be anode or cathode and both types are available in the market.
You can vary the shade of red, green and blue very easily by connecting each pin (red, green, blue) of the LED to a PWM output of a microcontroller and we will do the same for our project.
First thing first:
Take two RGB LEDs. Bend all the lags of the LEDs as 145 degree as shown in the image. Take another LED, keep it straight and solder the bent one with one side of it. Be sure about that, you soldered same pins of each LED together. Take the rest bent LED and solder it with the other side. Finally, solder a 10 cm long wire to each pin of the soldered LEDs.
Step 3: Preparing the Eggshell
Take an egg and wash the eggs with soap and water. Using a pin, poke a hole in the top of the egg. Just be gentle! You don't want to break your egg. Carefully enlarge the hole around 1 cm in diameter. Now drain the whites and yolk out of the egg and pour to a small bowl. This can be a little tricky. You might need to shake the egg a bit and puncture the yolk to get it all out, you can use the handle of a table spoon to do the job easily.
After getting the shell wash it with water clearly so that no whites or yolk remains within the shell. Now, fix the shell with a stick or wooden spoon with scotch tape. We will sink it in boiled water later with glue.
Step 4: Filling the Eggshell With Glue
Fill the half of the eggshell with hot glue. Then placed the soldered RGB LEDs into the shell above the glue. Now, fill the rest half with the glue. Sink the filled eggshell in the boiled water in such a way that 90% of the shell is placed under water. Wait 1 or 2 minutes to completely melt the glue so that no gap remain between glue and eggshell. Now, take it out from the water and give it time to be cool.
Step 5: Discovering the Glue Egg
After being cool remove the shell from the glue with your finger nail. You will get a cool egg of glue with integrated LEDs inside it. You may need to wash it in-case of any white membrane attached.
Step 6: Glue Egg!!! Impressive!
After washing out and removing membrane I found a very nice glue egg. I was impressed what I made!
Step 7: Making a Glue Wheel
Now, make 2 solid wheels using the glue. We will use it as base of our lamp. We are using two because we will place the circuit components between this two wheels. To make the wheel first make a paper ring shown in the photo. Place it in a plane surface and put enough glue in it. Wait for a while to make it strong and then remove the paper ring. You will get a nice glue wheel as shown in the image.
Step 8: Attaching Egg With the Wheel
Make a hole into the center of one wheel so that you can bring out the wires from the egg to the circuit through the wheel. Bring out the wires of the egg through the wheel and attached the egg with the wheel using some glue.
Step 9: Making the Circuit
Let me explain the circuit diagram first. The heart of the circuit is an Arduino microcontroller. We will drive the RGB LEDs using the PWM pins of the microcontroller. For controlling color an input is taken from a variable rheostat. A 10k potentiometer is connected with an analog pin (A0) of the Arduino microcontroller (ATmega328). Duty cycle of the PWM output is changed according to the input from the potentiometer. The potentiometer's value can be changed by changing the knob of it. Arduino sketch for the microcontroller is attached below.
For powering the microcontroller I added a 5V regulator LM7805 with the circuit. If you want to drive the circuit from USB power source, you don't need to connect voltage regulator. Just connect a USB power output directly to the power port of the microcontroller. You may also omit the on/off switch.
Let's connect all the components:
According to the circuit diagram solder all the component to a small pcb board. Select the size of the board according to the wheel. For generating multiple colors I used most popular Arduino mcrocontroller ATmega328P. Three pins (red, green, blue) of the leds are connected to three PWM pins (9, 10, 11) of the arduino microcontroller through a 100 ohm resistor in each pin. With pin #12 two white leds are connected through a BJT because microcontroller's pin is not capable to provide enough current for ultra bright white leds.
For soldering the microcontroller IC i used IC base, I always suggest to use IC base than directly soldering an IC to the pcb board. Upload the attached sketch to the microcontroller using Arduino board and place the microcontroller to the IC base of the circuit.
Step 10: Attaching the Circuit to Lamp
If you completed the circuit now it is the time to attached it to the glue lamp. Attached the circuit with the wheel which one is attached with the egg. Use your glue gun to do the job. Place the circuit with the lamp in a way that knob of the potentiometer can be rotate from outside. Others components of the circuit should be invisible from the outside for better outlook. After correctly placing the circuit add some glue to fix it with the wheel. Now, attach another wheel above the circuit and fill the blank place between the two wheels with enough glue.
Step 11: Final Step
Now, add enough glue between two wheels to tightly attach the wheels with the circuit. Add enough glue to completely hide the circuit without the potentiometer knob. Remove any extra glue by a knife as shown in figure.
Your Egg Lamp is now ready. Power up the lamp from an USB power source and enjoy.
Step 12: Enjoy!!!
Enjoy your multi-color egg lamp, show it to your friend and take credit from them.