The Mark VIII (4x CREE XR-E, 1x CREE MC-E)

[Techjunkie]

I've dubbed this creation the Mark VIII for it's 8 emitter dies. It could have easily been named the Phoenix 'cause it rose from the ashes of the XVII-Ray or The Flashlight that Never Was

It's a modded, bored-out, Mag 3C crammed with:

1 5*CREE XRE refelctor and base module (DX)
1x Neutral White CREE MC-E in the center spot :EDIT: MC-E is now warm white to match XR-Es (post 7)
4x Warm White CREE XRE around the perimter (KD)
2x single mode 2.8A buck drivers 5.5-8.4Vin (DX)
2x Sony 26650VT 2500mAH LiNiCoMn batteries

One driver runs the neutral white MC-E wired as 4p and the other driver runs the 4 warm white XR-Es also wired as 4p. Power consumption measured at the tail cap is ~20 Watts so runtime is estimated at just under an hour. These regulators work really well too, maintaining brightness through the entire discharge.

In the photos, you can see that I originally planned to coneal both drivers within the base cavity. I even took the time to tap new holes around the outside so I could mount one of the drivers facing down on the inside. Every time I'd try to close the brass ring, the compression would cause a short. After many tries, I finally gave up and the drivers now reside inside the Mag neck where the bulb post used to be, hardwired to the switch. The top of the Mag tube pushes right up against the bottom of the base module for improved heat transfer. Same goes for the reflector to head and base.

The effect of the mixed tints arranged this way is entirely unique. The hotspot although still more intense than the spill, is much warmer. The neutral white MC-E in the center intensifies the spill considerably compared to stock 5x XR-E. It's kind of a wall of light with bright warm hotspot.

I have all the parts necessary to make its twin. Considering that I've already mounted the center MC-E (and tapped out the holes which are now unneccessary) that's probably what I'll do, unless I can think of something else to do with what I've already started, or chance removing the MC-E from the center spot on the second base.

 

[smopoim86]

Re: The Mark VIII (4x WW CREE, 1x NW MC-E, Regulated)

I'd kinda like to do this as a have a 3d 12aa mag with a hotwire that is currently not getting used. Where did the heatsink and reflector come from?

EDIT: nevermind, i had a brain lapse... now to find a pile of neutral white emitters.

EDIT2: I couldn't find the reflector assembly on DX. There was what appeared to be that assembly with 5 p4s in it. was that the one you used? Could you link to the parts?

 

[Techjunkie]

Re: The Mark VIII (4x WW CREE, 1x NW MC-E, Regulated)

The DX sku for the 5*XRE reflector with base module is 18842.

They also sell a 5-mode 5*CREE driver that'll boost 5-8.4V input up to 17.5V out. If you change your 12AA pack to 6p2s, then you could use it. That DX part is sku 26106. I tried one but it self destructed after running on high for 5 seconds. DX is sending a replacement. I'm on the fence between building the twin to this torch or knocking the MC-E loose on the second one and trying once more to build the 5x warm white XRE with that driver.

I got the warm white CREE XR-Es from KD. I had seen them once while browsing and then couldn't find them with a search. I had to browse the entire DIY catalog before I could find them again. Their product ID number to enter in the URL is 5569. You have to trim the PCB as in my photos for five of them to fit. Don't forget to use the BUCKRATE discount code (all caps) if you order 3 or more of them.

Assembly is a real pain. I knocked the glass dome off of an XRE while trying to line it up and I wasn't even using epoxy at that point, just silver thermal grease. It makes me realize what a good value the fully assembled cool white modules that KD and DX sell are.

I wish I could find someone to swap either their WW MC-E for one of my NW MC-Es or their NW XR-Es for four of my WW XR-Es so I could match the tint of all the dies in the next torch.

 

[smopoim86]

Re: The Mark VIII (4x WW CREE, 1x NW MC-E, Regulated)

I'm after neutral white and my just order a pile of them from cutter... but i would really like to run a mce in the middle like yours. is the mce on no pcb the same hight as the xre's on boards? I was really wanting to do both in a series to keep the current balanced better.

Anyway, thanks for the inspiration.

 

[Techjunkie]

Re: The Mark VIII (4x WW CREE, 1x NW MC-E, Regulated)

The height of the MC-E bare is a hair lower than the XRE on a traditional thin MCPCB (not the newer, thicker MCPCB common with Q5 XRE and MC-E).

The height difference works out very well because the XR-Es are perfectly focused and the MC-E needs to be pulled back a little bit from the focus point to reduce the size of the donut in the hotspot.

You can tell from the photos that the emitters are al well focused in the reflectors. When they are, the yellow phospor of the die fills the reflector. When they're not, the reflector looks silver.

If you want to run your MC-E in series without the MCPCB, you can always epoxy it directly to the heatsink and then solder wires to each leg. I'd drill additional holes in the heatsink to run the series wires through underneath the LED to keep from criss-crossing wires up top. There's no room for clearance in there.

 

[Techjunkie]

Re: The Mark VIII (4x WW CREE, 1x NW MC-E, Regulated)

I received my fourth shipment of warm white CREE XR-E from Kaidomain today and strangely enough, they're neutral white, not warm white.

I knew something was up by the packaging. The first three orders (for quantity 1, 8, 3) had a piece from the plastic reel protecting the dome inside the bubble wrap. This time, no plastic, just wrap.

I was able to tell they were neutral white even before firing them up. I could see the tint of the coating on the emitters (while they're powered off) evenly matched the neutral white MC-E emitter. It was even more obvious after they were centered in the reflector. The cool whites have a day-glow yellow coating, the neutral whites less so, and the warm whites are almost orange. Look at the original pics above where it's obvious the XR-Es are warm white and the MC-E is neutral white.

I wish I had ordered four this time instead of three. I just ordered one more hoping to complete the set. For the time being, in the twin of this Mark VIII, I've got the three NW installed and one WW. The WW isn't epoxied so I'll be able to remove it easily.

I've built the clone unregulated, wired as 6p2s, using resistors to pull the voltage under load down to 7.2v. I think I might actually like the neutral white one better, even though color rendition looks better on the regulated warm white one.

---edit---
A picture's worth a thousand words...

warm white XREs on the left (5) neutral white XREs on the right (3)

 

[Techjunkie]

Just updating for my own record keeping... I've performed a transplant tonight, replacing the neutral white MC-E with a warm white MC-E so now all the tints in the Mark VIII match evenly.

Oh, so much better. The cooler flood with the warm hotspot was bothering me before. Now everything is uniform warm white.

The MC-E in the middle gets rid of the dark ring between the hotspot and the clover shaped spill that this reflector makes XR-Es in all five spots. Ironic that an MC-E should get rid of a donut instead of creating one.

As for the "twin", I had converted that to all XR-E long ago. Three neutral white and two warm white in that one, but all of them being the same emitters, the effect is a perfectly blended creamy white. Probably around 4500K. I used the DX 5*CREE 5-mode driver in that and I'm very pleased with the results there too.

You might think I'm crazy, pulling out the neutral tint (4A) MC-E to put in a warm white, but the result was worth the risk to me. I really like the Mark VIII now. Other good news is that the 4A MC-E escaped unharmed. I transplanted into a SmallSun 3C NiMH direct drive torch that I had formerly fit with a cool-white MC-E (in a 40mm MOP reflector+pill assembly). I can't remember what I did with the cool white MC-E that I pulled from that one...