I found the basic design for this on a web page that has long since expired. I'll be happy to give that person credit if they contact me.
In the spirit of ATM, I made a few modifications to better suit my needs. Below is a exploded view of the parts to my first
attempt. All wood parts are Oak from the local Lowe's and given three coats of spar urethane. The two vertical arms were later thinned from
3/4" to 1/2" oak (in the finished photos above). I also drilled a 2" diameter recess (1/16" deep) for the bulb shade to give it more surface
area to bond with the epoxy that holds the plastic to the wood. The inside of the shade, up to the LED, is painted silver.
By keeping a common power connector between the 3 volt power supply and the LED multiple systems can share power
supplies. Specifically, I can use this adjustable power supply to power the LED on my G11's polar scope. The power box was made from 1/8" Oak
bonded with urethane glue. It contains two 1.5 volt AA batteries, a 22 ohm resister and a 5K ohm pot to vary the brightness. The plug is a 1/8"
two conductor earphone style plug. Any on/off switch should work. The LED is a Jumbo super bright LED with the tip lightly sanded to reduce a 'hot spot'.
All of the electronics are from Radio Shack. You can also buy a small plastic case instead of making your own.
Velcro attaches the battery box to the base and weight of the box acts as a counter weight. With the battery box removed the light folds down for transport.
I ended up making three of these lights to use in trailer and on the map table. I generally leave them on all night and the batteries last through a dozen or so nights.