Actually, convoy S2 sized light radiates 1-2 Watts at 60C (25C ambient), calculator is here:
https://www.engineeringtoolbox.com/radiation-heat-transfer-d_431.html
Not much,but S2 has very small surface area, on bigger lights, or lights with fins, radiation can be very significant part of cooling.
Where can I find the available options?
I love seeing all the opinions, some closer to truth and some pretty outlandish.
FWIW, pure 100% oxygen free copper is orange in it’s raw state, bright beautiful orange. So is Tellurium Copper. Don’t believe me? Cut it on the lathe and see…
The pink hue comes from handling it….a reaction to the oils in your hand.
Pretty sure SinkPAD lists their copper stars at nearly twice the thermal capacitance of their aluminum stars, not 30% better. That should be worth something, considering the source. (Al’s 210.0 W/m.K, vs Cu’s 385.0 W/m.K) At 210.0 W/m.K * 30% the result would be 273 W/m.K, obviously copper fares much much better at ~83%+ gain over Aluminum.
I have a Hoop pill waiting for this light. Triple something or other it is! 
And I also just read recently that the anodizing gives Aluminum it’s thermal emissivity, the dye to change it’s color adds nothing… it is, after all, just dye in microscopic amounts…. (Type III being better than Type II as it’s a deeper ano)
Thanks JDub, and Simon, appreciate the willingness to please. 
I can’t argue with led4power’s formula’s and calculators, but I don’t spend the money on Tellurium copper for no reason, or just because it’s pretty or heavy. My lights built with heavy copper pills maintain their output in the light box for longer times. I did the C8 Trifecta on this years ago using copper heat sinks from ryansoh. It was clearly obvious how much difference the copper pill made over the aluminum one.
Let us not forget, cooling the emitters is mission critical, not keeping our delicate fingers comfy.
Might also point out that a full copper light heats up everywhere, get’s hotter in your hands AND heat’s up the cell inside a lot faster. Not necessarily a good thing, in some ways…
Edit: Not trying to be critical in any way, honestly, but I’ve built almost as many lights as led4power has posts in this forum! For the most part, extreme hot rods every one. Wow, how the time flies!
You’re right, I used the light’s volume instead of its surface area when estimating the radiated heat :person_facepalming:
I would’ve guessed for sure that convection and conduction do way more to transfer heat away. But of course it would be boring if I didn’t learn anything while being here 
Like I said, scour it under running water, before it gets the chance to oxidise (which happens almost instantly). It’ll be a salmon pink. Within seconds of exposure to air, it’ll have already turned that characteristic “copper color”.
It passivates almost instantly, so cutting it on a lathe, scouring it with steel wool, anything in air, and you’ll never see it in all its pink glory.
Take a slab of pc board, a Cu-bottom pan, etc., and try it.
So if something Cu is pickled and immediately coated, it can be a nice pink color.
“Within seconds…”
So when it’s spinning on the lathe and you’re cutting off the oxidized layer and watching the true nature of the metal spin around, you see it immediately, before air gets to it, under the oil, orange.
Reaction (and color-change) is almost immediate.
Maybe tinged by oil, maybe at higher heat, etc., sure, I’ll believe you when you say that’s what you see, but just try what I suggested. Take a rather large flat(ish) piece of Cu, and under running water give it a good scour. It’ll be a bright salmon-pink. I’ve seen this. As soon as you stop scouring, even under water, it’ll start turning orangey. That’s how fast the oxidation is.
Again, don’t take my word for it; try it.
Just for s&g…
“Copper just above its melting point keeps its pink color when enough light (the camera’s flash in this case) outshines the orange incandescence color.”
—
Hmm, and
“What you describe as pink is the actual colour of copper. The colour of a clean, solid surface of high-purity copper is typically salmon red. In your case, the appearance may be further affected by the particle size of the precipitate.”
Just sayin’…
Doesn’t convection have a bigger impact on cooling than radiation? Certainly with a slight breeze it would, but even with still air it must have a pretty big effect. Anyone know the actual number?
Convection is dominant part of cooling, otherwise flashlight would become hot much faster.
Well, as a rough guess, most small lights that are thermally regulated seem to stabilize their output at about 500 lumens, if you tail-stand them. That’s about 5 watts of power, with maybe 50% going OTF in light? If you’re saying 1 - 2 watts of that is radiative, then that leaves only 0.5 - 1.5 watts for convection.
Doesn’t sound like enough. I thought convective cooling would be 3 or 4 times what radiative cooling can do.
It is - at high power, ratio of convection/radiation dissipation depends a lot on input power/flashlight temperature. S2 head has very small surface area,1-2Watts is enough to increase temperature close to 60C over some time.
Specific thermal conductance/conductivity and specific volumetric capacitance/capacity are very different properties of material.
Copper has almost 2x times better spec. thermal conductivity (Sinkpad numbers you mentioned), but spec. volumetric capacitance is only 30% better.
Spec. volumetric capacitance determines how much temperature would rise when material receives thermal energy/heat.
Just noticed that these are all sold out now.
Mine shipped this morning, so the three week countdown to here has started. Thanks to Simon Mao and J-Dub74 for making it happen :+1:
I just ordered but wasn’t sure what options for driver or led was available, what are the available options.
You can basically ask for anything that’s available in another version of the S2. You can see the older S2 configurations here:
and the newer configurations here:
Other tweaks may also be negotiable, possibly at an extra charge.
I went with a 7135×8 Biscotti driver and an XPL HI U6-3A LED, along with AR glass and a smooth reflector. Basically copying one of the new Desert Tan S2+ configurations.
I’ve never turned a S2 into a triple… What’s the easiest way to do so?
If i could get a triple Nichia 90CRI drop in that works with the A6 driver that would be great.
You have to make or buy a spacer.
Copper is best, aluminum is good…
Kiriba-ru sells some, for a reasonable price IMHO