[PART 1] Official BLF GT Group Buy thread. Group buy officially closed! Lights shipping.

I was planning to do the same…I did a quick look and didn’t see OD for the bezel…anyone else know this spec??

I found somewhere TA said 134mm

He has not updated the last several payments yet, I am sure he will get to them soon.

Correct, just checked again on the V2 and it is indeed 134mm

Please add me to the group buy list. Thanks.

New * Cree XD16* , extreme density LED. This could be a game changing LED for throw lights.
284 lumens per mm2. 726 Lumens at 2A 6W. 1.6mm*1.6mm Can’t wait to see how it respends to higher currents.

The black flat does 900lm/mm^2.
You can also see from the datasheet that the 726 lumens at 2A is already at 400% output and it doesn’t look like it will increase to much more than 500 or 600% from the curve.
Assuming that you can get 2-3x more lumens like other cree LEDs that would still be less than 600-900lm.

Just received a DHL Express parcel (value USD$ 50) and DHL charged me USD$ 35 for “handling” and VAT.

That bill came in the mail a week after I had received the package.

… DHL Norway say: that when a package is shipped with DHL Express, you agree that DHL prepays customs, VAT and any other public charges for the importer.

So be prepared for an extra bill…

that’s the reason why i chose registered mail, no BS fee, slow but realiable

I’m guessing the die size is the same as the package size at 1.6mm2. This die size puts it in the range of the xg-g2.

The xhp35 has a die size of 2.35mm2.

You could put a XD16 or xg-g2 in the GT and get even further throw, but with less lumens and the hotspot size will be much smaller. It becomes more laser like and not as usable.

They do not have a middle terminal pad.
It has the same size as Nichia E21A. The board from clemence could fit: [GB ended,discussion only] CRI > 80+ NICHIA 2000K-6500K [E21A/219B/219C/319A/144A/757GT-F1(Optisolis)] - #1130 by clemence

These will typically have 1% or 0.5% tolerance today? I’m guessing that’s kind of necessary with such a low resistance, considering the typical application. If one could find a supply with a traditional “bad” 5% or even 10% tolerance, it would make things so much easier and you could just hand pick from a batch of 50 or 100. :smiley:

Yes, you would want 1% for sure, they are not that hard to find in the USA, Digikey, Arrow or mouser will all have them but overseas it can be harder.

Hi

Is there a specific plastic toolbox that you are using to make the case? just curious

Thanks

Paid with Registered Shipping but not on the list (yet) - please update! :partying_face:

The big waterproof padded case at Harbor Freight is $40. It has enough room for the length of the GT with over 2 inches to spare. The biggest con about it is the plastic it’s polypropylene and doesn’t appear to be fiberglass reinforced. That’s probably okay for a few years of use, or indefinitely as a shelf queen, but I’d accept that for now until I find a nice deal on a tougher case.

Cree’s 12/6/17 press release says it the first led to surpass 280lm/mm^2 lumen density. I know the top throwing emitters are in the 230-250 cd/mm^2. The units are different lm/mm^2 and cd/mm^2 but they are very related. So, does the Oslon chip really have 3.2x the lm/mm^2 of cree’s latest?
http://www.cree.com/news-events/news/article/cree-launches-industrys-first-extreme-density-led

I don’t see the appeal of the XD16 in flashlights aside from showerheads. It could be really good for automotive lightbars though. Most could use more throw. With them mounting just above the windshield, too much light lands on the hood. I’m not holding my breath though. Almost all the cheap chinese lightbars don’t use Cree, and many of those that say they use Cree are lying.

Yes it does. High density chips from Cree were never about high luminance. They have a high lumen density in terms of package size. It’s all about putting really big dies on really small packages.

High luminance requaires a very different kind of LED. It needs to have a very low thermal resistance and needs to tolerate a very high current/power density. Effieciency will always be low when you go the the absolute limits.

BTW: there is a rough formula for the luminance based on lumens/mm^2 (area of die, not package). Just multiply the value with pi (only works for de-domed LEds which are basically lambertian emitters).

Yes, but obviously not at the rated current.
You only get 900lm at about 6A which is like 400% the rated current.
The current-flux curve is better for the black flat than for the XD16. This means you get more improvement when you increase the current.
As you can see from the cree datasheet the 284lm/mm^2 is already half way up the curve so there isn’t much extra room for adding current.