2012-06-03 Watson’s Waterproof LED Flashlight

This pic is dated Nov 2003, which was about the time I built the light.  It was one of my early creations.  I built the circuit which used two transistors (not a true Joule Thief), a toroid, and three white LEDs. Most impottantly it used two AA cells in  series, which was kind of odd for the time.  The frame (I hesitate to call it an enclosure:-) was made from two short pieces of angle aluminum bolted to the bottom, a flat piece of aluminum.  The board and 2 AA cell holder were also bolted on.  It fit comfortably in the hand.

Since it was open frame, I decided I wanted to coat it wit a thick coating.  I bought a spray can of Grip & Guard, which is supposed to be used to put a thick coating on the handles of tools.  But the terms spray and thick coating are mutually exclusive: in order to get the can to spray, the fluid has to be thin.  I coated it with dozens of coats and you can see how thick it was in  the picture.  The only thing I really did was to get the switch gummed up so it was hard to turn on.  No, I really did not intend it to be waterproof.

The circuit lights the LEDs very brightly; in fact too brightly with fresh alkaline AA cells.  So I had to use depleted cells or else two Ni-MH rechargeable cells.  I still use it in some drawer somewhere.

 

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