I don’t have a dog in this fight, but I thought long ago that CPU heat sink makers had already settled this discussion about what works best. Copper to absorb it and aluminum to dissipate the heat with a press fit between the two.
When I say press fit I don’t mean a fit where the copper cylinder maybe .001” smaller than the hole and it has to be drove in. A press fit is a fit where the cylinder is actual a very tiny bit larger than the hole or the exact same size, no air gap. It must be forced into the hole sometimes using heat and cold temps.
Seems like I remember that too 007 and I’m currently asking about making some changes to the big copper pill on my M8. I see what is being said, there’s 2 sides to it, as with most things, and there’s compromise. So I’m willing to put some greenbacks on that argument and have a copper core pressed into aluminum fins, the copper to pull mass heat and the aluminum to disperse it. And more of everything. Dissipating the heat from an MT-G2 at 10A is a large order. Results are what I crave, regardless of the science that achieves it.
1+ :bigsmile:
Copper for thermal conduction, aluminum for convection. Anodized contributes higher emissivity then bare. Don’t polish your lights.
That’s what I said in post #957
moderator007 understands H)
um… you know we don’t have to hijack a great seller’s thread, we could open up another thread exchanging this idea and whatever kakameme scientific proof you guys have… let’s keep this thread clean and concentrate just on what’s the latest awesome stuffs on Richard’s store and maybe give a little guidance for some newbies who wants to build an awesome light 
Pretty sure that as a salesman RMM doesn’t mind one bit that we keep this thread on top!
I need some more CREE XM-L2 U2 1A LED on Noctigon 20mm MCPCB and Panasonic NCR18650PF 2900mAh Button Top Unprotected batteries 
Docturit, they were out 20mm XM Noctigon boards at the manufacturer when I placed my last two orders but more have now been produced and are on the way. The PF button tops have also been shipped and should be arriving this week.
I really hate being out of stock on anything. Generally I plan ahead but there have been a few unforeseen circumstances that have left me without: manufacturing delays, shipping (weather) delays, and sometimes someone will come along and buy an unusually large amount of product. 
I'm not against using copper, just that some applications will benefit from it, and some won't, and on the ones that won't it's not worth bothering with.
Here's one design that it can really help with. Without the copper, there'd be a big difference in temperature between the top and bottom of the slug. A press-fit core like this is the only way to make use of the entire chunk of aluminum to maximum extent.
Cool comfy! I like it. I'm a believer in copper in the core, alum to cool in the outer layer..
Thanks for the info Richard. I guess I will have to wait a while on the LEDs. I was just hoping that they would be in by the 12th of this month due to having surgery on the 12th. Doesn’t mean that I can’t order stuff while recovering. Now if you see me order something crazy like 10 of everything at the store PM me cause they might have me on some good pain meds and I am not thinking right. 
This is why I’ve asked Buck to consider making a new light engine/pill for my M8, making it bigger around to give more surface contact to the ambient air, and longer to do the same, out of aluminum to maximize heat transfer out, with a copper core to maximize the pull of heat from the big MT-G2.
According to what you guys are saying, this should be the most effective possible combination to cool the 10.5A emitter and keep me buying more and more of Richards best cells to supply it with the power it’s hungry for.
I have a new cell to try in the S6, might be better than the 20R, we’ll see.
In a quick test of cells in my direct drive Triple XM-L2 1D Mag, the 20R is awesome! Albeit dethroned! 
Samsung 26C - 5.4A
Panasonic PF - 7.7A
Efest 35A - 9.73A
Samsung 20R - 10.39A
Beta Test Cell - 11.21A
Powerizer 26650 10.36A
By the end of the week I’ll have a couple of the Sony C4 cells to add to this.
Beta Test Cell? Are you a "top secret" beta tester now? 
Gotta know what this thing is.
Heretofore un named. And making the 20R and Powerizer look bad.
Unfortunately, it’s only 1500mAh capacity. I’m checking with my supplier as to when information can be released, but thought y’all would like to know there’s a new contender on the block.
Crap! I was think'n the EFEST 35A was your BETA, so I ordered 2 from RMM, expected to be here today... Still, they made a good showing for their capacity.
Oh - C4's are probably not as good as the C3's, from published internal resistance #'s, but I was wrong before... 
What is the rated capacity of the beta cell?
I don’t have any info as to it’s chemistry. I just know it delivers a punch. I got it in a surprise package in the mail today. Lot of questions out, haven’t heard anything back yet.
The Efest 35A is not the 20R killer I thought it might be, could be if it lived up to the 35A hype, but that said, it’s a good cell and falls just short of the 20R’s performance in both my M8 and the only other Direct Drive capable light I have, this triple XM-L2.
It might prove out to have a better life than the 20R, as it is supposedly a 2500mAh cell compared to the 2000mAh of the 20R. Efest might be rating the 35A on a pulse instead of continuous discharge, that hasn’t been figured out yet. No doubt it’s a strong cell, but just where it’ll end up in the pecking order is not yet established.
Surprised at the low capacity of this new cell I just ran, but power is power. Makes me wonder what the AW IMR18650 1600mAh cell is capable of? Isn’t it supposed to also be pretty potent? The new Sony is 2100mAh, right? So there’s a lot of jockeying for position going on. Or simply, we can see where the limits are.
Hi Richard, are you going to offer us Triple XM-L2 on Noctigon anytime soon ?
Thinking SONY added capacity with sacrificing resistance, but not sure til proven... I miss the Powerizer soooo much. Got 2 cells, but really wanted many more.... The SONY 50A 26650 does close to the Powerizer, but love the Powerizer's capacity.
Where did you see a triple XML/XM-L2 Noctigon? Oohhh - wishful think'n...
If you’re thinking 20mm size, I don’t think there are any triple-optics that fit XM-L sized emitters. The standard Carclo triple TIRs will fit de-domed XM-L2s, but not domed ones.