Aluminium • Electronics • LED
December 9th, 2014
While searching on Amazon, I found most flashlights were too “tactical” for my taste so I decided to make my own. I also thought this will be great way to learn more about DC power supplies like boost controllers and constant-current drivers.
The torch is charged via a mini-USB port and accepts a 5v power source.
The area around the port lights up and pulsates to indicate the torch is sucking in electrons.
The power button sits flush with the body.
The brightness achieved was beyond my expectations.
In my own use case, I always found orienting a flashlight to be difficult and unnatural. For example, when you hold a flashlight to aim in front of you, you need to rotate your wrist down so the flashlight is perpendicular to your body whereas the more comfortable and natural position is to keep the wrists stationary with the length of the flashlight parallel to your body, but now you are pointing the flashlight upwards.
I want to design a torch that makes it easy to aim at a target, not only while holding the torch but also when its set down on a surface. The hexagonal shape gives the torch six sides of stability and by having the light come out from the side rather than on the end encourages a more comfortable holding position.
To keep the aesthetic to be as clean as possible, the decision was made to not have any externally visible fasteners and the enclosure should be milled from a single piece of aluminium.
After some quick sketching it was off to prototyping.
My early attempts at learning about power supplies and LEDs led me to make these prototypes that uses a single AA or AAA battery to drive one to three mid-power LEDs.
The size of the torch increased as the prototypes showed the initial design felt too small in the hand and the size wouldn't accommodate a high capacity LiPo battery. Since all the components had to fit inside the torch from only one end, I had to design a “carriage” where all the custom PCBs and battery will be adhered to, that will then slide into the torch. A lot of sketching had to be done to determine the size of all the internal components.
Working out the outter dimensions.
Figuring out the dimensions of the carriage. This is also made of aluminium so that it will act as a heatsink for the high-voltage LED driver.
Since there is limited space inside the torch, all the PCB had to be custom designed.
LED driver board.
Charging / battery management board.
From the left: completed body, turned round stock for the carriage, test piece for drilling a 5" diameter hole and test piece for milling the pocket. Smaller pockets were milled out underneath the LED board to help with weight distribution.
Freshly milled body.
This 6" deep hole took forever to drill out.
Everything was soldered by hand.
My little corner of fun.
Charging board complete.
Making sure the mini-USB port sits in the middle from all sides.
The completed carriage with the battery and PCBs attached.
Programming the MCU.
Finished carriage with body.
Created by Dickson Chow
Speacial thanks to Hannah for making an awesome table!