I did a homemade switch for Physical Computing class. I decided to make a lantern with a mason jar. The idea was to create a switch with the jar lid.
I used 5 LED lights, 5 resistors of 36 Ohms and 2 batteries of 3V. To figure it out how much resistance I needed I used the led calculator.
I did a parallel circuit and tested with a breadboard, and started sketching to figure it out how this circuit would look inside of the jar before I started building.
I soldered the LEDs, resistors and wires.
I placed the batteries on a battery holder and aluminum paper on both sides under the lid. The red wire (positive) connects to the aluminum paper on bottom and the black wire (negative) connects to the aluminum paper on top.
Where the lid touches the glass jar, I placed a small piece of aluminum paper on both sides to connect the positive and negative wires. The resistors are on the negative side (top).
When the lid closes the lights turn on. The positive side of the lid touches the positive side of the wires, and the negative side touches the negative wires by the use of aluminum paper as a conductive material.