The Cree MK-R is a pretty interesting emitter. 200lm/W at 6v or 12v, it seems like a pretty comparable LED to the MT-G2.
However, the cost is much much less. You can get 5 of them on copper for $25 here (and for $20 other places that I won’t link to because I can’t verify their authenticity). I can’t get an XM-L on copper for that much!
Considering we’re a…thrifty?…bunch, why isn’t this emitter finding its way into more projects?
1. It doesn’t throw
2. High vf
3. Ugly beam
My understanding is that it’s also not really any brighter than the MTG2…. an emitter which has much prettier tint.
There’s a Selfbuilt review on CPF of a prototype of the Niwalker MM18 with 2xMK-R. He compared its flood to the Niwalker MM15 which had 2 MTG2. He reported that output from the MM15’s 2xMTG2 appeared to put out more lumens than the 2xMK-R in the MM18.
He also found out that the only reason Niwalker went with MK-R for their new light is that unlike the MTG2, the MK-R was available in cool white.
As modders, I guess if we’re going to go through all the time and expense of buying a host, machining it to fit, obtaining a driver, and then assembling it… we’d rather spend a few bucks more and get the prettier tint of an MTG2.
Thanks, very insightful. There is an MK-R in warm and neutral white (with the former being available at 6 and 12v and the later only at 12v). I understand the argument though, when you build it yourself you build it to spec.
The specs on that link show 118 lm/W not 200.
I’ve got a triple 12v MK-R project in the works using a TN30 host (with the LED’s in parallel) and a current bump, should be a pretty cool light when I’m done.
CK, can you push these MK-Rs like you can with MT-G2s?
No clue, this’ll be my first time ever even seeing one light up in person. I’ll certainly give it a try tho lol. I’m figuring 3 12v emitters in parallel on DTP copper should be able to handle whatever I can coax out of the TN30 driver.
Wonder what a 20mm boost driver and the cool white 6v would look like in a SK98 host
I wonder if those copper stars are true DTP or the ones with the dielectric substrate blocking heat flow
I would bet money that they are not direct copper like a sinkpad. Looking at the back they look like the same poor quality as the ones with the dielectric substrate. Still if you take the time to lap them down nice and flat you can drive them fairly hard. If you really want to you can even sand it down so that you make a kind of sinkpad out of them.
Oh and thanks billnye I might just have to give them a try. Not sure what on but probably something floody with multiple emitters to even out the beam pattern and maybe mix and match some warm whites with cool whites.
Theres a light built with one here.
18sixfifty, you’re exactly the type of crazy guy who would do this:
J19 (with 3 batteries) with 3 12V MK-Rs with a zenner modded BLF FET driver. I think it would work!
My question is: why would you chose MK-R over MT-G2 besides it being cheaper?
Its 1/4 the price. Should have similar output. Available in cool/neutral/warm. But really price is it.
The quad die thing is the real downside I think. We went through that already with Cree’s MC-E and SSC’s P7. A big die is much better than quad die for flashlight applications.
So I bought 5 MK-R’s here for a whopping $4 a piece. They arrived, slowly and without tracking, but they came.
I swapped the emitter out of my Yetzl Y3. No driver modifications or anything, just taking the XM-l out and putting a dab of artic silver and the MK-R in its place.
Pulls around 17 watts from my PS with the worlds most high resistance leads from a harbor freight DMM and about 18-19 watts from 3 26650s. And it’s very very bright. I’d estimate 2k lumens.
The beam isn’t smooth (you can see the separation between the dies if you’re white wall hunting inside), but outside it’s a great light. It took a while to center the emitter, and now that it’s where I want it I will never open the head again. But a $4 mod that doubles (at least) the output of a light I bought for $25 - that’s what BFL is all about!
very nice!
Hmm, that does sound legit. 
I won’t pay $10 for one on eBay and the 5pc MOQ at $4/ea… hmmm.
Another stuff to cram into a Courui converted to 3S.
anything to compare it with? any lux numbers? ryanferg