Introduction: Long Lasting Ultra Small Super Bright Bike Flashlight

After trying unsuccessfully several commercial bike flashlights, I decided to make me one that cover my needs:

- Lightweight and very small size.
- Rechargeable to prevent the continued waste of AA batteries.
- Cheap!!!
- Powerful and long-term for long night cycling routes.

Due to my limited knowledge of electronics, I assume that the circuit can be improved, so any help comment  or suggestion with this, will be welcome ;)

Step 1: Materials Needed

- Old Cellular phone with working battery and charger (as charging station).
 - Rf switch cable TV adapter from an old video game console or some similar size plastic case.
- Hard disk or some electronic device with contact pins.
- A small switch
- 10 white ultra bright leds with prototyping board for welding circuits.
- Solder
- Bicycle clamp from a broken bike light
- Wire

Step 2: Lights and Case

- Place the leds in parallel on the prototyping plate as shown in the picture.

| - +_|_+ - |
| - +_!_+ - |
| - +_!_+ - |
| - +_!_+ - |
| - +_!_+ - |
          |       |
         +       -

- Open the RF adapter and remove the inside circuit / wires to get the plastic box empty .
- Take measurements of the led board and cut / sand the plastic box until led board fits perfectly into.
- Unscrew the clamp from the old bike light.
- Mark in the plastic box where to screw the clamp and make the screw holes.
- Screw the clamp to the box ensuring it is firmly attached.

Step 3: The Battery Holder

- You must find a good way to attach the battery that allows you to easily replace to charge it.
- I have chosen a pin connector from an old hard drive.
- Unscrew the pin connector from the hard drive and remove some pins until you have only the positive and negative pins and a pair more for holding the battery.
- Sand the pin board until it fits into the plastic case.
- Solder wires to + and - respectively.
- Solder the positive wire from the pin board to the positive leg of the led board.
- Solder the negative wire from the pin board to the switch and from the switch to the negative leg of the led board.

Step 4: Finishing...

- Put the battery inside the plastic box making all components fits well and the polarities are correct.
 - At this point, maybe you will need to adjust the position and size of the inside components, so sand if you need before gluing the pin board!!!
- Turn on the switch and check if pin board makes good contact to the battery...
- If it works correctly, it's time to glue the pin board to the plastic case ;)
- Close the plastic case and plug the bike clamp...

Ready to go!!! ;)

When the battery runs out after SEVERAL hours of use, all you have to do is remove the battery and place it on the phone to recharge again...
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