The incandescent bulb found in most flashlights does not provide a light as bright as a comparably-sized LED bulb. You can build a simple LED flashlight from a breath-mints box that will provide a bright light even as it conserves battery power. Parts from an electronics store will be needed along with skill with a soldering iron. The simple LED flashlight you will build will be more dependable than a flashlight using an incandescent bulb and will provide a brighter light source when needed.
Instructions
1
Put some newspaper down on a table. Empty the contents of a plastic breath mint box. Drill a small hole at the bottom of the breath-mint box. Drill a slightly larger hole in the top of the lid of the box, and then pull off the lid.
2
Duct tape three AAA batteries together with the positive contacts all at the same side. Cut six 3-inch strips of electric wire using the wire cutters. Strip the insulation off of both ends each wire using a stripper.
3
Solder one wire to the top of the leftmost AAA battery. Solder a second wire to the bottom of the same battery, and solder the other end of that wire to the top of the center battery. Solder a third wire to the bottom of the center battery, and solder the other end to the top of the rightmost battery. Solder a fourth wire to the bottom of the rightmost battery.
4
Solder the free end of the wire attached to the top of the leftmost battery to one end of a 27-ohm serial resistor. Solder one end of another wire to the other end of the resistor. Solder the free end of the wire attached to the resistor to one contact of the LED. Solder another wire to the other contact of the LED. Solder the free end of the wire attached to the LED to one end of the micro switch. Solder the free end of the wire attached to the bottom rightmost battery to the other end of the micro switch.
5
Insert the micro switch into the plastic breath-mint box and push it out of the bottom hole. Insert the LED into the hole in the lid of the breath-mint box.
6
Put the batteries with their wires and the resistor inside of the plastic breath mint box. Apply some bonding glue to the rim of the lid and put the lid onto box. Apply bonding glue around the micro switch hole and let it set to cure.
7
Press the micro switch to illuminate a bright beam of light from the simple LED flashlight you have made.