Cool, Efficient, Mag-lite




Replace the bulb in a 2xAA mag-lite with a bright white led. A cool burning led will give you longer battery life and won't burn your face off.

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Step 1: Collect the Parts

You'll need a 3.2 volt LED -- I think most bright white LEDs qualify. A ruler or caliper. An old, beat-up mag-lite, the kind that takes 2 AA batteries. Some wire cutters. A low speed or variable speed drill and 1/4" bit (not pictured). A small vice or pair of adjustable, locking (vice-grip style) pliers will come in handy (not pictured).

Step 2: Disassemble the Head of the Flashlight

My old mag-lite was already missing the bulb. Unscrew the front part of the head to gain access to the parabolic mirror.

Step 3: Drill Out the Hole in the Plastic Mirror

Place the plastic mirror carefully in a vice, hold it with a pair of slip-joint or vice-grip pliers... or if you have the hands of an oil-rig worker, with your fingers. Slowly drill out the center hole of the mirror with a 1/4" drill bit. This will allow the mirror to fit over the LED.

Step 4: Trim the LED Leads

Trim the LED leads to 1cm, .4 inches, or 3/8". You could probably go a little shorter to put the LED closer to the focus of the mirror, but this spreads out the beam the way I wanted it.

Step 5: Discard Mag-lite Bulb and Install LED

Wiggle the LED around until you can insert the leads into the two small holes that used to hold the mag-lite bulb leads. The LED should light up if the batteries are installed. If not, flip the LED around. Remember, this model of mag-lite is turned on by unscrewing the head of the flashlight.

Step 6: Screw the Head Back on the Flashlight

All done!

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    74 Discussions


    7 years ago on Step 5

    The only rechargeable 1.5 batteries are the rechargeable alkaline type. Nicad and NiMH are 1.2 volts (1.37v hot off the charger) and never 1.5 volts. If you have a rechargeable Nicad or NiMH marked "1.5v" show me a photo. I don't like the rechargeable alkaline because they leak.

    1 reply

    Reply 7 years ago on Step 5

    that comment was retarded made at 4 years ago and we all knows im wrong about rechargable 1.5vs

    come on shut your yap and move on!


    13 years ago on Step 5

    No current limiting resistor? How long has it been burning? Does it work with rechargables?

    10 replies

    Reply 11 years ago on Step 5

    It says 2AA battery equal as 3V, and this LED is 3.2V, so nothing is bad. And yes, rechargable works too, because they works as 1.5V each.

    i don't know i'm looking at my collection of batteries... (and i have a TON of AA's) and they all say that they are 1.5.... including the rechargeable ones.... what brand are you talking about???


    Reply 7 years ago on Step 5

    All my rechargable AA's say 1.2 V
    Just my 2 cents.. Where did you get rechargables that are 1.5?

    Rayovac, Radioshack, Sanyo, and a couple more generic Chinese brands that I have. If yours are newer and 1.5V, that's great, more compatability. But as of a few years ago when I bought my last ones, the standard seems to be 1.2V for rechargeable AA's.

    hmmm well then this is all news to me... this will be very helpful to me and my projects.... Thanks for the info 


    13 years ago on Step 6

    light output might actually be greater than the maglite bulb, depends on the led's mcd. If you find a "superbrite: white, the LED will make a laughingstock of the old bulb. Alternative to drilling out the focus (reflector), you can find the same ratings for ini's and sub-mini's that will fit without any modification except to the LED lead length. You will know a superbrite if it's hard to tolerate it shining directly into your eye, and perhaps leaves a bit of retinal burn.

    5 replies

    Reply 10 years ago on Introduction

    Pointing superbrite LEDs at your eyes can cause retina damage it's a very bad way to do it :)


    10 years ago on Introduction

    I have GOT to make this... im going to buy a flash light just for this =)