13,333 lumen Nichia 319A "Mega M6" by Texas_Ace, I had to use over 6 feet of wire to reduce the power!

Flashlight Modding and DIY Parts Featured Mods
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So I have been out of the modding game recently but I decided to use up some spare parts and built my version of the MTN “Mega M6”. No, it doesn’t make exactly 13,333 lumens, just a number I got at one point, it is between 13k and 14k depending on the batteries and charge level.

Cliff notes version:
Had spare parts, decided to build Mega M6
Decided to run it in a 4s3p setup instead of 12p
realized doing this would make it FAR too powerful to be useful at 280w+
added over 6 feet of wire to reduce the power to a more reasonable ~200w (~150w with the GA cells I use)
converted tailcap to 4S and used a TA driver that made the 4S conversion rather simple
got a completed light that outputs 13-14k lumens of beautiful Nichia 319A 5000k 80cri white goodness

Long detailed version:

A BLF member was nice enough to make me an aluminum slug spacer to raise the tripe optics up to the lens and the rest of the parts except for the mcpcb’s I had laying around (actually got enough to build 2 more lol).

So this is an M6, I had it modded with XP-L HI’s and while it was good and made 4k lumens, I just never used it compared to my other SRK’s.

The mod was pretty simple really. I put the spacer in, drilled a hole for the wires and then reflowed the mcpcb’s. I then wired up the LED’s with 18 AWG wire in a 4s3p config in order to vastly reduce resistance losses.

I put the head back together and started playing with it on the bench power supply. I quickly realized that this thing was going to be a monster if I was not careful. Wiring it up in 4S means that it can achieve much higher output then if it was wired in 1S (Richard said he gets around 40-50A out of his). I maxed out my power supply at 15A (equivalent to 60A at 1S) this is already over 200W of power and the voltage was only a bit over 13V!

Some math showed me that it with high drain cells I could easily see 20A+ (80A+ at 1S voltage) if I didn’t do something. Seeing as 280W+ would be far far too much I decided to do something. I added over 6 feet of 20awg wire as a crude resistor to drop the power!

This increased the voltage at 15A to around 15V which was much more reasonable and means that the 30Q’s should also give around 15A by the math (turned out this was correct).

So for those that have asked if running a SRK in 4S will net you more power then in 1S. The answer is easily yes.

I then put together a TA46-Multicell (the one that splits the voltage instead of using an LDO) and put the head together. Only to then have to rip it apart again as I tried to track down an issue with the driver. Never did figure it out, spent an hour on it and then reflowed everything and it suddenly worked. So some joint must have been bad.

After that was sorted I then had the hardest part of the whole build, lining up the driver with the battery tube so that the springs were centered in the bores. Turns out if you do not tighten down the centering ring real tight after each adjustment, it will just change every time.

Last came the tailcap mods to convert it to 4S. I used the multi-cell tailcap for the Q8 and set it up for 4S. I used some 1/8” brass rod I got for $3 from lowes to create locator pins in 2 of the holes. I simply used a touch to heat them up and soldered them to the screw holes in the PCB.

I then drilled a hole in the tailcap, sadly the M6 doesn’t have a divot in the tailcap to center the drill bit on but I got it almost exact by using the tailcap as a guide through the battery tube.

I inserted a screw into the tailcap with a small o-ring for water proofing and then used a nut to clamp it in place.

The tailcap pcb came next, the center hole went over the screw and then another nut over that. Lastly I added yet another nut on top to tighten against the last nut so that it would not loosen when taken the tailcap off.

Thats it, the 4S conversion was really quite simple and the light works great. I think I will upgrade to narsilM later as the LVP is kicking in early on the 1.2 I am using.

The results are quite good. Around 13-14k lumens with 30Q’s @ ~14-15A although I run it on GA’s where it is closer to 10A and around 11k lumens.

It has some great 319A 5000k 80CRI LED’s that give a nice wall of pure white light. The best flooder I have yet.

It is funny though, it is not by brightest light and since it is so floody it doesn’t even seem as bright as it is. Still very usable though and I think it will become my standard around the house light.

Now for some pictures of the completed light:







Here it is hanging out with a few of my other SRK’s:

Lights in order:
Mega M6 - 13.5k lumens
8x XM-L2 U2 3D - 10k lumens
8x XHP50 J4 1A - 17k lumens
4x XP-L HI V2 3B - 4500 lumens





These are all great lights. The XM-L2 is very close to this mega M6 except that it doesn’t have DTP due to the stock mcpcb and it is in 1s. The output quickly drops down to ~8000-8500 lumens due to this. The tint is good but not quite as good as the M6. It is a trowier beam though as would be expected from the larger reflectors.

The xhp50 is a lumen monster, very bright but once again lumens drop off due to lack of DTP, they settle around 12-14k IIRC. Ugly 1A tint, only keep it around because it is my brightest light right now.

The 4X version is very nice indeed, very close to what the Q8 should be like except with XP-L HI’s. Good combo of throw and flood and still had good output as well. I can’t wait to take it to the next level with the Q8 and XHP35’s, should be 8k+ lumens and great throw.

Here is a first for me, some really bad beamshots in the same order as above:





Well, this is how I spent my weekend.

2

Holy shmoly, that’s some serious equipment.

3

Great mod! Thanks for sharing. Now, I want to see the 6ft of wire. You didn’t take a picture of the 6ft of wire? :open_mouth:

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lol, it is all coiled up inside the driver cavity, I didn’t have 6 arms to hold it in place and take a picture at the same time. If I decided to reflash the driver I will snap a pic then.

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Yep, 4s with super low Vf LEDs… Looks like your eyes were bigger than your heatsink. :smiley:

Nice light.

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Nice way to spend the weekend :+1:

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This light is begging for a buck driver, it could run for quite some time in full regulation. The Texas buck would be perfect for it. I might end up building one of those someday and using it. 10A seems to be about the sweetspot, past that it is quickly diminishing returns.

This does give me an idea what a quad xhp50/70 Q8 would do though and it is great.

Another interesting point is that the M6 is much heavier then even my modded SRK’s with solid shelves. It takes a bit longer to heat up from cold due to the higher thermal mass but it gets significantly hotter and stays hotter for much longer.

I was playing with 2 of them at similar power levels and they both got real hot so I set them aside to cool. Came back later and the SRK was cool but the M6 was still surprisingly warm. I never really realized just how effective even those tiny fins on the SRK are.

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Very nice!
How much feet of wire could you have saved by not bypassing the springs?

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The springs would have reduced the power enough by themselves most likely but they also would have melted in a few seconds. Anything over ~5A per spring and I have not had the best luck with longevity with un-bypassed springs.

I bypass anything over that just to keep them from melting later.

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Whats there to say but wow. :slight_smile:

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Awesome work

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What is the length and diameter of your creation?

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Of the M6 light itself? It is just a normal M6 on the outside. Quick measurements put it at 145mm tall by 60mm wide at the head.

Although it is one heavy beast, a bit over 1.5lb total as it sits right now.

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How was the OD on the slug?

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The slug was fantastic and worked perfectly, you did a great job! I had to sand off about 2mm as planned but it was worth it since I didn’t know exactly what the compressed optic height would be.

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This light is still going strong, really liking the smooth floody beam for tasks that need it. Boy does it get hot though if you turn it up too high! Strangely it gets hotter and stays hotter then the SRK by a fair margin, those tiny fins really do something.

For those that wanted to see the wires in the driver cavity, I opened it up in order to glue the tube to the head now that I know it is working so I was able to snap this picture.

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How much of that heat is due to the wires playing ballast resistor in the driver cavity?

Do you think replacing some of the 319a’s with XP-L’s would get the current under control without the wire?

Finding the right tint could be hard but it might help spread some of those lumens around.

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The wire is adding some heat but not enough to be noticeable. In total the light is around ~200 watts of output. The wire might be dissipating around 10W max. The heat is mostly due to lack of surface area, there is just no place for the heat to go. I have an 8x xhp50 17k lumen SRK with similar wattage but it stays a bit cooler and cools down noticeably faster due to more surface area.

Doubtful that a few XP-L’s would be enough to drop the current by themselves, it would help but unlikely to be enough to make a big difference unless you replaced like half the LED’s.

The best idea would be a buck driver. The Texas buck should be capable of driving these fairly well but no one has tested it yet.

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That 10 watts is just adding heat to an area that is already too warm but I guess there’s not much else you can do.

What happens if you do more pulse width modulation and put a decent size capacitor in parallel with the led’s to reduce the flicker? I know its a bad idea since there are a lot of smart people here not doing it, I just don’t know why. Even adding some resistance or a choke between the capacitor and the led’s is a lot simpler than going to a buck driver and has a better chance of fitting in a small light.

One of these days I need to get back to working on my M6 mutt. Two xpl hi’s or dedomed xml2’s with Ultrafire spot lenses on one channel, triple xpl hi with Carclo spots on the second channel and triple xpl hi’s with a smooth spot on the third. Probably fet,fet,7135 on a bastardized version of bistro that emphasizes flood at low levels and the spot’s on higher levels. The first step is not screwing up when making the spacer.

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10W is a less then 5% of the total output of the light, which overheats in about 90 seconds on turbo. It might last 95 seconds without that heat but it will still overheat in a big hurry. There is simply too much power for the host.

You could limit power via PWM, the results would be ok, the efficiency would drop some and most likely balance out the heat from the wires if not a bit more to get the same output. I chose the wires so that it would limit power no matter what batteries I put in it and it was simpler then trying to find the perfect PWM.

Adding an output capacitor is actually a perfectly workable idea, the issue is size and cost. You would need a very large cap to make any noticeable difference with 200W of power flowing through it Getting it to fit in the light would be a challenge and it would cost a reasonable amount as well. If you could figure out those issues it would work fine and improve things a fair amount when under PWM.

In a light this size, you might be able to make it work. In a normal 17mm driver, there is just not enough space to make it worth it.

If you need a spacer for the 20mm Carclo triple, justanotherguy did mine and it turned out great. I had him add in some extra height to ensure I could sand it down to a snug fit but turned out my original measurements were almost spot on and I bet he could make you one for a reasonable price if you need it.