LED upgrade for Wietek military flashlights

Custom PCB with 3W LED and boost converter to replace the internals of a vintage flashlight

Joris Wegner

Following Follow project

Liked Like project

Become a Hackaday.io member

Just one more thing

To make the experience fit your profile, pick a username and tell us what interests you.

OK, I'm done! Skip

Similar projects worth following

View Gallery

Description

My grandpa once gave me an old flashlight from the German army. It collected dust on the shelf until I got a jacket the flashlight could be attached to. I replaced the internals, consisting of a small incandescent light bulb and huge batteries, with a custom pcb carrying a 3W LED, a boost converter and a battery pack for standard AA cells.

Details

This was just a quick project after realizing how comfortable it is to have a flashlight attached to your jacket. It proved to be ideal for long hikes in the cold woods when you rather want to put your hands into your pockets.

I used a schematic I found online and it works very well. The batteries last quite a while and the flashlight has just the right brightness - It illuminates the way nicely without glaring everybody.

I did the design with KiCad. I also had a lot of fun while making the silkscreen pattern.

Files

WietekLampConversion.zip

KiCad files

Zip Archive - 3.17 MB - 10/26/2018 at 20:34

Download

Components

1 × Wietek Bundeswehr-Taschenlampe I guess there are a lot of versions of this lamp out there. Unfortunately I don't know a lot about them except for the fact that they are very cheap on ebay.
1 × Custom PCB Hit me up if you need one or make your own
1 × ICM7555 DIP package
1 × 1uF film capacitor 5mm pitch
1 × 3W LED

View all 16 components

Build Instructions

Collapse

1

Add PCB mounts to the flashlight

I glued four M3x18 screws to the chassis using cheap epoxy. The unpopulated pcb served as a template. I carefully adjusted the position of the screws until the footprint of the LED was placed exactly above the hole in the reflector. I also carefully removed some of the reflective coating on the reflector that faced the inside of the lamp using fine sandpaper. It seemed to be conductive, so it is just a safety measure against shorting out the leads of the LED.
2

Modding the original internals

I wanted to continue using the original switch of the lamp. Therefore I soldered the wires from the battery pack and the PCB to the former battery and lamp holders. I had to shorten them quite a bit using a dremel to have enough space for the PCB.
(All the components are already in place because I took the photos after completion, sorry for that)
3

Solder components to the PCB