Match I have to say your work is incredibly impressive. Takes something practical and useful and makes it just sexy.
More Match-Madness… and I keep telling myself that I dont need a lathe. MUST RESIST!
Just send me a PM. This sounds so awesome I need to ge one.
Thanks! If something is worth doing to excess, might as well try and make it look good in the process. In this case however, form follows function, and nothing functions better at taking heat than good old pure copper.
Heh... But you do, you really do need a lathe! ChicagoX has the deal of the year on a very nice 9x20 right now. I'd buy it in a heartbeat if I didn't have one(2) already.
I don't want to get ahead of myself, so I'd hold off on any PM's till it's done and actually works properly. Heads up though...something like this won't be exactly be the most budget light out there.
Thanks for following. Progress update soon to follow.
Very nice!
@ Match: A one piece heat sink directly conducting heat away is unquestionably the best way to go. The heat gets quickly removed from the source but regardless of the material being used, it’s the convection at the limited surface area exposed to moving air that ultimately determines the amount of cooling. Using a parting tool to create the fins leaves pockets of stagnant air that act as an insulator! The valleys should radiused and not too deep so natural convection can take place down to the roots. The fin’s profile should be triangular (not square) with their peaks terminating at a rounded point to allow air to move in and around every surface easily. A heat sink designed for forced air flow can have deep, closely spaced fins but with natural convection, fins need to be shallow and widely spaced. Keep up the good work! 
Except silver… diamond… isotopically pure diamond… and a few things best not talked about…
don’t remind me - the knowledge of that stunning deal that is causing me great angst both for how much I want it and how much my wife would kill me (many times over) if I bought it.
someone buy it, please!
any updates. i am sure everyone is quite curious. i have to say one of the things that i like the most about this build is that at this time and as far as i know this will be the brightest light of its size. that in its else is impressive. keep up the incredible work
Lightme,
Welcome to blf! Your points on fin design are quite valid - for a conventional light. This however is quite unconventional and I have no illusions of extended runtime in high. The fins are more or less for aesthetics, and all the radiusing in the world won't help this wee build dissipate 35 watts of heat efficiently.
texaspyro,
Yes, I imagine the Hope Diamond would make one heck of a great heatsink. Hard to machine though... 
Dieselpusher6262,
Post updated above!
Thanks for the update Match. Its looking real good.
There are commercially available diamond heat spreaders, etc that are actually reasonably priced. Also things like diamond-like carbon. Graphene is supposedly the Next Big Thing… I’ll believe that when I see it…
This is fun to watch. Thanks for posting this build.
Nice work and I'm looking forward to hearing about lumens! :D
Any updates?
Any updates? this has been about the only light that has really peaked my interest lately. It seems everything is going to a much larger design.
You have done some great flashlights and mods. Really unique. Nice to follow you work. Thanks for sharing, I’m getting some really good tips from these threads.
Super quick update! (I'll update the original post this Sunday when I have better data):
The good:
- The 18650 body is made, and machined for the control ring.
-Control ring is made (went with thin knurled steel for strength/longevity).
- Control ring works - going from zero to max in < 1/2 turn.
- OTF lumens are ~1880L.
The bad (still work in progress):
- No matter how hard I try, and despite my lack of updates I've been trying a lot, I can't get the damn ring to have a nice smooth feel to it. If I go to a higher thread pitch, I run into too much ring travel, if I go lower I get too much physical twisting resistance. Not only that, but as others have noticed the qtc resistance points change - so much for having the body marked at proper output levels.
- Despite being absurdly bright, I was expecting a slightly higher otf value. I believe the culprit may be that my fluke is lying to me about the current output (probably < 8amps). I'll know for sure this weekend when I hook the head up to my bench power supply to find out.
Here's a quick photo comparison between this and my triple xpg NW. The distance to the tree/tree house is 38yds, the woods behind it are at 42yds, and the exposure has been turned down. Mouse over for the quad:
One last shot at my poor garage door that's sporting a cross for aiming made out of red duct tape. Distance is 33ft. :
Thanks for the nice comments and for following what is turning out to be a very frustrating mod!
-Match
p.s. - please ignore the nametag on the quad photos... I was in a quite foul mood when uploading the shots. 
Match,
The QTC may not be able to handle the amperage. Also, it may "wear out" more quickly because of the amperage. As you found out, the ring will never be repeatable more than a time or two, but will change, so don't bother with marks or detents, just let it be a ring. I wouldn't worry about too many turns either. You may not prefer it, but ultimately the method that produces the best results, may not be what you had in mind.
Please take my thoughts as just my thoughts, not anything else. Just an old guy wandering in the middle of the stream (without waders).
I love the build and the QTC idea. I would love to see something different and more hardy in the way of compressible material for lights like this.
Can you post a pic of how you trapped/encapsulated the qtc? Thanks.