Installing LEDS, Optics and Electronics
Here are some shots of my Triple Cree XR-E LED bike light. They are P3 binned XR-Es, being driven at 750 ma using the nFlex controller. Battery power is from a 14.8v, 4A, Li-Ion battery pack. This light uses 3 Ledil square optics that fit nicely inside the one inch, square aluminum tube from which the light is constructed.
Ledil Optics (Two 9 degree diffusers and one 4 degree spot). 3 Cree XR-E (P3 bin) LEDs on stars. 1 Custom made light housing
Closer view of the Crees and the Optics
Bottom side of Ledil square lens with sticky stuff. Made to fit right over the skinny side of the Cree emitter. This bottom surface required some alteration to fit over the solder and wire on the face of the star.
Bottom side of star inserted into bottom of optic. (Left the sticky backing on for fitting purposes). In fact, I glued the stars on like this so that they would be centered in the sections of the housing. I filed the bottom of the star to make sure it was flat since it is a stamped  piece of aluminum. You want it to mate nicely with the mounting surface for maximum heat transfer.
Getting ready to fasten the stars with Arctic Alumina Adhesive. AAA provides, adhesion and good thermal conductivity while not being electrically conductive (or capacitive). Use a very thin layer.
They're on now! I can still pull the lenses off... in fact I still have to drill holes for the wires and solder them to the stars. I marked the bottom side of the lenses because they have to fasten over the Cree in a certain way.
Stars in tact. Middle one looks crooked, but it seems to fit together well this way!
Close up. It might be better to apply the layer of AAA to the back of the stars, but I just spread it across the mounting surface. I probably used more than I should have. A thin layer is best.
End view
Wire holes drilled. Ideally, you would do this before mounting the stars... test fitting and marking where the holes need to be drilled. I drilled them after mounting the stars, and that risks slipping and damaging an LED. Yeah, I know, the middle one is crooked, but it turns out it didn't matter.
Another shot... without the flash. Man I wasted some AAA... that stuff is expensive.
Getting ready to build a ship in a bottle. Getting all those wires, connector, and switch in there is a challenge. The PC board is the nFlex controller. The connector is a female, M-Type DC power connector from Radio Shack. Wires are about 24 ga.
Let the fun begin. Thread wires through the places they belong, and start working the pieces inside. It's a tight fit, but it will all go if you are patient and plan things out.
Pulling wires and trying not to damage the nFlex. It must really be durable, because it survived my soldering and all this shoving into the body... I tried to be gentle.
It's all inside. I still have to insert two pieces of rubber washers inside to insulate the nFlex from shorting against the case. In fact, before you power up, be sure to examine inside a close as possible for wires shorting to the body or each other.
Top of Cree star after soldering. The lens base will have to be modified to accomodate the solder glob + wire.
Base of Ledil lens after modification to fit over soldering points on top of the star.
You can see the rubber washer insulators in place now, and all wires are soldered in place. The nFlex fit inside very nicely. I believe a bFlex should fit fine in a similar arrangement.
Close-up of momentary contact switch and one end. The momentary contact switch controls the operation of the nFlex.
Optics sans case.
Optics and little light in hand.
The new design housing (left) with the Crees and Ledil optics and the TriLux III (right) that I built last year. I've simplified the design (10 screws down to 2) and it sits lower on my helmet. The new light weighs 130 g. In fact, one nice thing about this design is that it makes such a great helmet mount light because of its low profile.
Back side. Notice rubber feet.
In low power mode with battery space 14.8v 4000mah Li-Ion battery pack. The nFlex controller lets you choose to drive LEDs at 350, 500, 750 or 1000ma. It then has 5 levels of dimming within each of those. I'm running at the 750ma level with the Cree XR-E (P3 bin) LEDs.
Another shot with a quarter for size comparison. I guess this coin is a worthless size comparison if your not from the U.S.
Notice clearer 4 degree spot lense in the middle and two frosted, 9 degree, diffuser lenses on outside. It seems to be a pretty good combo.
Ceiling Beamshot comparison. Distance: about 12 feet. Triple Cree XR-E on left, Triple Luxeon III light on right. The Cree XR-Es are much whiter than my TVIJ bin Luxeon IIIs, and I like the larger hotspot area (partially due to the optics).
Here's a shot of the light mounted on top of my helmet using two velcro fasteners. It is very lightweight and low profile compared to many helmet lights.
This shows that Luxeons are not the only LEDs with a lottery. The Cree lottery is alive and well. Notice how much yellower and dimmer the left LED is compared to the other two. This shot is a closeup beamshot (about two inches). In the middle you can see the actual emitter's die pattern projected by the 4 degree spot lens. The outer two are the 9 degree diffusers. Keep in mind that this was a power setting that was about as low as I could run and still get the LEDs to light. Additionally, I stepped down the exposure on the camera. At full power you don't really notice that one LED is on the yellow side of things.
Here's a better shot of the finished product. The Ledil lenses fit so nicely in the square aluminum tubing. I still haven't sealed the light for waterproofness in this photo. And some polishing can be done to get a better finish.
Fenix P1 3W Luxeon LED flashlight. A very good choice to throw in your camelback for emergencies. A very small light, measuring 2.5" x .75", it will run for 2 hours with its CR123A lithium battery... plenty of time and enough light to get you out of the woods! About $45. A worthwhile investment. This series of beamshots at about 25 feet. All at F2.8, 1/4sec, ISO 400. They are a little overexposed.
Dual Luxeon V Bikelight. The best flood of all my lights, and makes a great handlebar light.
Triple Luxeon III bike light. This has been my helmet light for last season and this season so far. Good bright light, a bit on the long throw, spotlighty side of things.
Triple Cree XR-E (P3 bin) bike light. I think this is my new helmet light!
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