Before you toss that 35-millimeter film canister, check out how simple it is to turn it into a flashlight.
- Step 1: Solder the short end of one wire to the uncut long LED lead. Solder the short end of the other wire to one of the leads on the push switch. Solder the remaining non-U-shaped end to the remaining lead on the push switch.
- Step 2: Cut two more pieces of wire four inches long and strip off a half-inch of insulation from three of the four ends. On the remaining end, strip one inch of insulation and bend the exposed wire into a "U" shape.
- Step 3: Solder the non-U-shaped end of this wire to the uncut short lead.
- Step 4: Using electrical tape, tape the two U-shaped ends of wire to the battery, connecting the positive side of the battery to the wire that is soldered to the push switch, and the negative side of the battery to the wire that is soldered to the uncut short LED lead.
- Step 5: Push the switch to test that your LEDs light up. Then, drill a hole in the film canister large enough to accommodate the switch.
- FACT: Conrad Hubert, who introduced the electric flashlight in 1899, left the bulk of his $9 million fortune to charity when he died in 1928.
- Step 6: Put the switch through the hole from the inside of the canister, and place the battery in the canister, making sure it settles comfortably on the bottom. If you need to, add a little hot glue around the switch to secure, and put the lid on. Congratulations! You have built a canister LED flashlight.
- Step 7: Cut another piece of wire four inches long. Strip one-half inch of the insulation from one end and one inch from the other. Bend the longer length of exposed wire into a "U" shape.
- TIP: If your LEDs don't illuminate, check that you connected the battery properly. If this isn't the problem, you probably soldered a positive lead to a negative lead.
- TIP: Add a little hot glue to the base of each LED to secure it in place. The glue won't conduct electricity, so it's OK if it touches the leads.
- Step 8: Insert the two leads of the LEDs into these holes so the bulbs poke through the outside of the lid. Alternate between long and short leads.
- Step 9: Use a sharp knife or a needle to poke eight small holes on the underside of the canister lid in four pairs, just inside the edge. Evenly space out each pair of holes so they are at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock.
- Step 10: Cut eight one-inch pieces of telephone wire. Strip about a quarter inch of the insulation at the end of each piece.
- Step 11: Solder the eight pieces of wire to the middle of the leads in parallel. This means the long (positive) leads should be soldered together with four pieces of telephone wire, and the short (negative) leads should be soldered together with the other four.
- Step 12: Test your work. Hold the positive side of the battery to the long uncut lead (the positive lead), and the negative side of the battery to the short uncut lead (the negative lead).
- Step 13: Using the wire cutters, cut six of the eight leads down to the solder, leaving one long and one short lead uncut.
- : Be extremely careful when working with a soldering iron. Always keep the tip away from your skin, and never set it directly on a work surface.