100w LED Flashlight





Introduction: 100w LED Flashlight

It this tutorial Ill be teaching you how to build an extremely powerful flashlight!

Its very easy to make, and extremely cheap as well!

This flashlight has many uses, Pure white light means its great for filming. Or you could use it as a motion activated spotlight in your backyard! The possibilities are endless!

Step 1: Gather Supplies!

You will need

Metal box (used as a heatsink)

12v battery

100w LED

Thermal paste

12-35v step up transformer

Thats it!

You will also need assorted tools

Step 2: Connect Some Wires!

Add connections to the 12v battery and wire it directly into the transformer

This is not permanent because we will be adding a switch here later

Step 3: Step Up Voltage

Using a multimeter measure the voltage of the transformer.

Use a small screwdriver to slowly turn the voltage up to about 34 volts

Step 4: Add a Switch

Now cut one of the wires going into the transformer and add in a switch

You will also need to use a dremel to cut a square into the metal tool case and feed the switch through there.

Step 5: Scratch Away Paint

Using a dremel, scratch away the paint until you have a big square that can fit your LED

This is alot harder than it looks and took about an hour.

Step 6: Final Touches

Now add some thermal paste and mount the LED directly onto the metal parts, being sure that the positive and negative tabs dont touch.

Then solder on wires from the transformers output onto the correlating LED tabs (+ and +) (- and -)

Step 7: You're Done!

You're done! You now have an extremly bright flashlight!

Thanks for reading my instructable!



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    nice, can you help me here


    Have a look at < >. The presenter uses a variable power supply to show that many of the LEDs are actually defective!

    I have a bit of a fetish for LEDs and LED lasers, especially since living next to China, in VietNam, where we buy LEDs by weight and not by the count - at least up to 3W units.

    My LEDs are from an importer which means my supplies are 'loose' - and one of the things I buy are circular alumin(i)um PCBs. The conductive tracks are insulated from the alumin(i)um by a carrier film.

    Where the LEDs are situated are naked circles of exposed alumin(i)um so that heat transfer, using heat conductive paste, is optimised.

    The LEDs are of the builders choice, the only constraint being the PCB, but I use 3W units connected in series / parallel which is the choice of the professional illumination companies. They never use a single high-power LED. The series / parallel configuration allows the LEDs to be driven at optimum levels from a 12V power source. And don't forget a breaker or fuse in the power feed.

    Power consumption is minimised by use of PWM based on a 555-timer chips and a handful of components. The frequency and waveform ratio can be preset or brought out as controls.

    In a couple of my larger 'flashlights' I have mounted a single LED laser - green is best for temporarily blinding people - under a separate control. I use stainless steel Grade 302 for my cases.

    I use LEDs on my motorcycles for daylight running lights, the headlight, etc. Bus drivers, who tend not to dip their headlights for motorcycles, get respect when I crank all the LEDs up to brightest.

    It would be less confusing to call the DC-DC converter by its correct name instead of calling it a transformer (which is an AC-only device).

    I don't mean to take away from your main point, because you are right, but you CAN use a transformer for some special-case DC work.

    nicely done. here is one i built. 100w led as well


    Awesome! At first glance I thought it was a 20W in a flashlight body, but looking closer, it's much bigger than I thought!

    thanks, it is 2.5ft long. the tube helps the fan keep things cool.