Cree LED ID, PCB dust & base modification

MrNaz

Enlightened
Joined
Jul 20, 2006
Messages
244
Location
Melbourne, Australia
Three questions:

1. How do I identify the folowing LED:
I think it is a Cree R2 WG, I purchased it from DX as this item:
http://www.dealextreme.com/details.dx/sku.15943
But the light that it gives off is very cool compared to what I was led to believe a WG emitter was supposed to put out and also the markings on the base differ slightly.

2. I would like to upgrade my Romisen RC-N3 to fit this emitter with a direct drive from the CR123A battery. However, the heat sink has a space for a 16mm board while this is a 20mm star. Can I safely dremmel away the star into a 16mm circle?

3. I was dremelling a PCB earlier and noticed that the PCB gives off a very fine strange smelling dust. I immediately ceased doing it and decided to check if PCB dust is in any way harmful. If so, how should one go about machining a PCB?

Thanks guys!
 
You cannot identify the flux bin of any current Cree LED by physically looking at the LED. The only thing you can tell by looking at a power LED is the manufacturer, the model (XR-E, XP-C, etc), and sometimes color (and I don't mean tint, I mean blue, red, white).

Aside from checking the bond wires (most easily obtainable Cree XR-E's now have 4 bond wires), you will not be able to figure out what flux bin your RC-N3 is. (Or the LED you got from DX for that matter). The only clue I can give you is that my RC-N3 from DX running on RCR's is just as bright as my Friend's Q5 RC-N3 from Shining Beam on two AA NiMH's. However, when we both run RCR's, the Q5 clearly has the brighter beam with more throw.

If you're talking about identifying the LED from DX... You'll just have to trust them. Thats why some people don't purchase bare LED's from them. Also, if you're trying to judge tint... I suggest you place the LED under your RC-N3's reflector first. To my eyes, even my warmest LED's look cool when not under a reflector. When I focus the LED they end up warmer ;). I donno why. - Like flux bins, there are no external markings on the LED that can safely tell you what tint bin it is. You will just have to trust the seller.

If you are planning on swapping emitters, I suggest you get a Cree XR-E Q5 on a 16mm board. Also, I suggest you keep the current driver inside the RC-N3, as direct driving from a CR123 primary wouldn't be very bright and it would dim over time. I'm not sure if you'll have enough of the star left to make connections.
 
Binning means they produce a lot of leds. Than they are tested for brightness and color and put in the different cathegories. So two leds with different bins might look exactly the same.
 
2 LEDs from the same tint bin can also different from each other. 2 LEDs from different flux bins but of the same tint bin can have the same visible tint. You'll have to trust the seller.

I do remember seeing people sanding, clipping, or some way making the star smaller so it should be fine.
 
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