Building a New Light

Last year the big American LED maker, Cree, introduced a new LED called the XP-G. It was similar to their earlier XP-E, but had a bigger light emitter. I got a light with this LED in it recently and liked it. Then on the flashlight bulletin board someone was talking about ordering some of these LED’s from a supplier in Australia. Cree will sell you LED’s, but only 1,000 at a time. There don’t seem to be many US suppliers, so this company, Cutter, is maybe the best bet. But they charge $12 minimum for shipping an order to the US. So a guy in Hawaii was trying to organize a US-based group buy to divide the shipping costs, even though he also had to charge us for shipping once the LED’s were in the US (he bought 10 LED’s total).

In particular he had his eye on some XP-G’s in a neutral tint. Most LED’s are “cool white” meaning they have a kind of bluish tint. But really the LED is very blue but has yellow phosphor on it that makes it appear white when the yellow and blue mix. If they put more phosphor on the LED, they can get a “warmer” tint, but it blocks some of the blue light and so the warms are usually not as bright as the cool tints. But these LED’s were a neutral white and only one increment of about 5% below the brightest cool whites (the brightest being an R5 and these being R4). In the group buy we could get them for about $10 each, so I bought two. Oh, and by the way, Cree is in North Carolina, so the LED went from Raleigh to Atlanta via Australia and Hawaii. It is on a circuit board smaller than my pinky nail.

I thought I would put one of the LED’s in a P60 drop-in. An empty drop-in needs an LED and a driver (circuit board, different than what the LED is mounted to). So I also bought a circuit board from DealExtreme that seemed like it would be okay, but it was only a 1-amp driver and I’d really rather have a 1.4-amp driver for more brightness. DX sells a board with 3 regulators soldered in place for 1050mA and they leave room for a 4th that would bring it up to 1400mA, but I don’t have any regulators, so I picked one that had 3 and no room for a 4th. But before everything could arrive, a dealer in New York started offering a 4-regulator chip with 3 modes and no flashy stuff, so I bought one of those.

After a few weeks I finally had my empty P60, my LED, and my driver. So I glued the LED into place with some thermal glue that I had to buy, and soldered the wires from the driver to the LED and it worked! I put the drop-in in my WF-504B host that previously had a slightly less bright LED in it (an R2 brightness, some of my other lights, including the tiny flashlight, are Q5 which somehow is one increment below R2), but otherwise is very nice. This light did not disappoint. It is very bright (not as bright as my big light but brighter than anything else), the tint is like a regular incandescent bulb (which is supposed to render colors better than cool white). I have taken it when walking the dogs at night and it really lights up the sidewalk ahead. I really like having this light and it isn’t something that I could buy already made unless I had it custom-made by someone else. Also the LED was the most expensive part, so it was also pretty economical throwing together the other parts needed.

Here is a picture with the neutral white LED shining on the left and the cool white LED on the right:

Leave a Reply

Your email address will not be published. Required fields are marked *