Replacing Old Flashlight Bulb With LED

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Introduction: Replacing Old Flashlight Bulb With LED

It was my boy finding this classic flashlight and asking me to make it works. Replacing the batteries with new ones didn't make it work. Then I took it apart, saw that the bulb's flashing wire had broken. Searching all around (my house) I couldn't find a replacement bulb. Seeing two AA batteries (3V) made me think of replacing it with a white LED. Why not? I have plenty of them around ^_^

Step 1: Parts and Tools

Parts :

  • A classic 2 x AA battery flashlight.
  • A white LED.
  • 2 cm of small cable [18-22 AWG will do]. We need its jacket only.

Tools :

  • Wire cutter.
  • Solder.
  • A small head screwdriver.
  • Hot glue [optional].
  • File [optional].

Step 2: Get the Bulb Base

Take off the bulb from its base. It is small and fragile. You just need to move it left-right-left-right until it get loosen, then pull it out. Clean the whole base using a small screwdriver.

Step 3: Prepare the LED

Bend the cathode (-) of your LED forming 90 degrees from the anode (+) of the LED. Well, for instant, the larger piece inside the LED is cathode and the smaller piece inside is anode. So far I keep remembering LED anode-cathode in this way, because I was once wrong when using longer-shorter pins due to factory's fault. For more confirm, please connect the led directly to 3 Volts battery, it won't light up if you put it the wrong way. Then bend the pin connected to the negative (-) of battery just like the photo above.


Get a small piece of wire, we need its jacket only, any wire whose jacket fit the LED pin. Pull out the wire strands, then put the LED anode (+) pin in it. This is to avoid shorting to the negative base.


Now bend the cathode (-) pin down to the former bulb negative solder pad then smoke it... I mean solder it there :)


We are almost done :)

Step 4: Finishing

I use clear tape to seal the border of the anode (+) pin to avoid short. Actually I intended to fill it up with hot glue to make the LED steady on its new container but at that time I couldn't find one, while the deadline given by my son was expiring that day :D

So.. I lighted it up anyway.



If you have a file handy, clean up the bulb negative contact which will be touched by the sliding switch connecting it to the negative of battery.


A happy Son, a happy Father, and an old stock brand new Flashlight ^_^

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    15 Comments

    cool very inventative :-)

    Thank you. Just do my best for iBle community ^_^

    been needing to do this to my old MAG light' the bulbs are just to dull, but never could figure out if I needed a resistor or not for it thank you very much great ible

    Red, yellow or green led has 1.8V forward voltage , yes you need 48 ohm resistor. But for white led, it has 3.3V forward voltage. I am using 2 AA batteries (2 x 1.5 = 3V) so I don't need a resistor. If your battery voltage is more than 3.3V then you need a resistor. Here is a good explanation about led and resistor needed :)
    http://www.evilmadscientist.com/2012/resistors-for-leds/

    You can use it without a resistor but you should use a resistor because without one the LED won't last long.

    Nothing better than father overcoming an obstacle to make him "shine" in his child's eye- nice work dad!