Crank Flashlight Charger




Introduction: Crank Flashlight Charger

Learn how to turn a crank flashlight into your own personal charger!

Step 1: Take Apart Your Crank Flashlight

Remove all screws and separate the two pieces of plastic, covering the flashlight. 

Step 2: Get a Charger for Your Desired Phone

Cut the cord closest to the connector that goes into the wall. Once you have done this, you will need to take off some of the casing, exposing the inner wires of the cord. In our case we used a USB cord and cut off the USB port to reveal our wires. 

Step 3: Removing the Circuit Board

Unscrew and remove the circuit board from the crank shaft while also disconnecting the blue auxiliary wires from the circuit board. Allowing them to be connected to your charger's excess wires. 

Step 4: Putting It All Together

After exposing the blue auxiliary wires and your charger's wires, inter twine the negative blue auxiliary wire and the negative wire coming from your charger together. Then inter twine the positive blue auxiliary wire and the positive wire coming from your charger. For best results, it is recommended that you use electrical tape to secure the wires together. (Alligator clips are also an options and work as well.)

WARNING: do not crank too quickly for you may cause damage to your charging port due to the lack of resistors. ( removed with the circuit board previously)

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    7 years ago on Introduction

    This is dangerous and likely to damage your phone battery as there is no voltage regulator and spikes from rapid winding could ruin your phone

    As dan2525 said, you need at least a zener diode AND a resistor in a small circuit to prevent damage.

    Just buy a crank flashlight with the USB port already built in. It saves hours of work and is read to go, and you also have a working rechargeable flashlight


    8 years ago

    U could buy a Zener diode to Attach to blue wires so u don't worry about messin up your phonr