Flashlight Without Batteries--from the book, "Haywired"

In this project, you will make a flashlight that works without batteries. Even more amazing, you can recharge it in three minutes and it will run for more than 24 hours. Because the ultra capacitors can be recharged thousands of times, you may save the environment from ever receiving an old flashlight in the trash system. Parts List (2) 220 farad capacitors,, #589-1013-nd Insulated wire, black and red Solder LED, high brightness,, #217525 12" x 12" acrylic plastic sheet, 1/8" thick Permanent marker (2) C clamps Epoxy 1/4" jack, Radio Shack, #374-280 Metallic tape SPST rocker switch, Radio Shack, #275-693 Glue Electrical Tape Tools List Wire cutters Soldering Iron Scoring knife (for plastic) Single-hole paper punch 3-volt DC power supply--700 milliamp Drill 1/4", 1/16", and 3/4" drill bits Metal straightedge

Flashlight Without Batteries--from the book, "Haywired"

step 1Put capacitors in series

First, solder a wire from the (+) on one capacitor to the (-) on the other capacitor.

step 2Solder wire to (+)

Solder a 4-inch length of red wire to the unused (+) terminal on the capacitor. You will call this capacitor wire (+).

step 3Solder wire to (-).

Solder a 2-inch length of black wire to the unused (-) terminal on the capacitor. You will call this capacitor wire (-).

step 4Correct method to cut plastic

Next cut the 1/8-inch plastic sheet for the flashlight case. Generally, this is accomplished by scoring the plastic, then breaking it along scored lines. But first, mark t…

step 5Scoring Plastic

Using the scoring edge (not the knife tip) pull the knife along the fine line several times until you create a groove. The plastic can now be snapped along the score line. …

step 6Start the case

Now you're ready to build your flashlight case. First, cut out three 1 1/4 x 7 inch pieces of plastic and glue them together with epoxy. This is the flashlight body.

step 7Install jack

Cut a plastic piece 1 1/4 inches by 1 1/2 inches. Drill a 1/4-inch hole and insert the 1/4-inch jack. Hold the jack with one hand (to prevent it from rotating) while thread…

step 8Add wires to jack

Solder a 2-inch-long black wire to the end of the jack near the tab. Solder a 3-inch-long red wire to the other side of the jack (away from the tab).

step 9Attach jack to capacitor

Solder the red wire from the jack to the capacitor (+). Solder the black wire from the jack to capacitor (-). These wires form the path that will be used to charge th…

step 10Prepare for LED

Cut a piece of plastic, 1 x 1 1/4 inches. Drill two 1/16-inch holes in the center, side by side, the same distance apart as the leads on the LED. Cut a piece of metallic ta…

step 11Place reflector and LED

Remove the paper backing from the tape and fasten the tape to the plastic. This is part of the reflector for the flashlight. Insert the LED leads through the holes.

step 12On Off switch

Cut a piece of plastic 7 inches by 1 1/4 inches. Drill a 3/4 inch hole 2 1/4 inches from the end. This is the plastic switch holder. Press the on/off switch through the ho…

step 13Attach wire to switch

Solder one end of a 6-inch length of black wire to one end of the capacitor (-). Solder the other end to the on/off switch.

step 14Capacitor (+) to LED

Solder the wire from capacitor (+) to the long lead of the LED.

step 15LED to on/off switch

Cut a 2-inch length of red wire. Solder one end to the short lead on the LED. Solder the other end to the on/off switch.

step 16Glue jack piece to flashlight body

When the switch is on, power will flow from capacitor (+) through the LED, through the switch, back to capacitor (-). This will cause the LED to light up. Carefully place t…

step 17Separated jack and capacitor

Cut a 1 by 3/4 inch piece of plastic. Insert it into the flashlight body, between the jack and the capacitor. This will prevent the capacitor from sliding into the jack; th…

step 18Cover on/off switch wires

Place electrical tape over the on/off switch wires.

step 19Glue LED holder

Glue the LED holder into the flashlight body.

step 20Form reflector

Place metallic tape inside the flashlight body and on the plastic switch holder to form the reflector.

step 21Finish assembly

Glue the plastic switch holder to the flashlight body. Cut a 1 1/2 x 1 1/4 inch piece of plastic for the lens. Glue the lens in front of the LED.

step 22Charge and use

Plug a 3-volt DC power supply, (+) tip, into the back for three minutes. Remove the power supply and enjoy your new flashlight.

Via Instructables, Published: 2009.03.22

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