TR-J12 HYBRID: 1 x MT-G2 + 4 x XM-L2... It Works!

Flashlight Modding and DIY Parts
1

This is a mod that I've been wanting to do for a while. I wasn't sure if it would work, but after asking my fellow BLFers a lot of dumb questions, I was hot to trot.

The J12 host is pretty small, but it arrived the day I decided to do this build, and it looked like an MT-G2 would fit in the center emitter hole.

I used a BLF17DD FET driver from RMM with a Zener mod. My copper clad circuit board came in handy for shaping a contact board that everything would be mounted on.

Right after I took those pictures, I realized I had meant to have the battery+ go directly to the LEDs, so I had to tear it apart. It's not as pretty now, but it works.

Since the reflector would be sitting directly on the MT-G2 substrate it would be a little higher than where it should sit on the XM-L2s. Since this was just a prototype, I didn't want to get into all kinds of technical mounting logistics, so I used Sinkpads which are a tiny bit thicker. In the end, it worked well enough.

Three parallel leads from the driver with 2 x 2 series XM-L2 and 1 x MT-G2.

What was bothering me, was the thin film that covers The MTGs substrate and prevents shorting was peeling off. Even after this pic was taken, it had all fallen of, leaving fully exposed +— pads on the top.

This emitter came out of my very first MTG TorchLite build. The host that started the MTG craze on BLF. That was before Noctigons, and it was on an aluminum MCPCB with a 5A driver. I wonder if that caused the the protective film to fall off

I put Klapton tape around the reflector hole and hoped it would not short out.

it seemed to work. Yea!

I hot wired everything with magnets and alligator clips to get a few measurements before I tucked it back together.

Mt-G2 on high at the emitter.

XM-L2 at the emitter.

Anyway it works. It's daylight out so it needs to wait. I'm really tired, and my cat hates me. I just wanted to get this light built.

I thought the current readings would be a little higher, but I guess thats a lot of emitters for two cells.

I tried to take a wall shot, but my ipad camera ignores all the periferal light and condenses it all into a hot spot. It's really bright.

I'll see if I can do better outside at night.

I'm not sure, but this may be the first MT-G2/XM/L2 hybrid light. It was a fun project.

2

What an effort. You know we need lots of outdoor pictures now.

3

Very cool. Nice build.

4

Yep, cats like moonlight mode best.

Nice for humans, though.

5

Wow! Really nice! This has been talked about, but you are probably the first to do it. I think Richard was suggesting that. I know Dale was considering this for a J12 he was repairing who's driver died - oops, I was the one that resistor modded that specific J12 and upgraded to XM-L2's on copper, but I warned the owner to not use 2 cells - amps go thru the ceiling, but on 3 it's much more reasonable.

Interesting combo of amps too. It must be generating some incredible heat.

I was thinking of trying it with a J18 - also odd # of LED's. I just got in two AK-47's I won on eBay for $45 each. Was thinking of using a BLFDD driver on this one - 3 cells, 9 LED's is a good combo though so planning on keeping them all XM-L2's.

6

I forgot to mention that I used XM-L2 U2 2C. They seem to compliment the MTG nicely. I was going to use 1A because I had them at hand, but had RMM add some 2C to an order that was being prepared. I don’t think the 1A would have been so nice.

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When I was wondering about the current level, I realized that in my other 9XML light, I kept the stock XML, and this one has XM-L2. XMLs would have showed higher current.
It does get pretty toasty on high, but I have five modes. Low is really low. I wanted to add more heat sinking, but couldn’t get the head apart. It must be glued.

I don’t think you can do it with a TR-J18. The math just doesn’t work…my math anyway. Seven emitters are a pain in the butt modding wise. The number seven just seems to defy everything.

8

For a J18 (6 XM-L2's, 1 MT-G2), wouldn't it be 4 sets of wires for the two cells? Just one more set of wires in parallel?

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Did you mean MT-G2?
Sorry Tom. I was only thinking of the J18 as a three cell light.
I think Two cells would really be pushing it with seven emitters (eight really if you account for MTG). As it is, I can see the current falling with my five emitters. Mind you that’s expected on high with DD, but I really think it would be tumbling fast with the J18.

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Here's some quickie beamshots taken with an ipad from my balcony.

Modded TR-J19 5A per XML2

Convoy L2 with MT-G2

TR-J12 1 x MT-G2 + 4 x XM-L2

As you can see, the J19 and Convoy L2 want to throw farther, but the little TR-J12 floods out the whole area. The tint mixing with XM-L2 2C is wonderful.

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Well, I don't think the J18 will get as high as the J12 with amps per LED. With my J18 with 7 XM-L2's, 9X beast driver, I got 7A measured at the tail with 4 cells, and about 9K lumens - it is insane!

The other J18, I have it only populated with 6 LED's (center one removed), and using the 7X beast driver. Best #'s I got were ~7.5A at the tail with 3 cells, and about 6.6K lumens.

12

Theres nothing like quickie beam shots. The modded light makes it look like someone has been pruning the jungle. Did it melt the greenery? Thanks. I've said this before but you gotta love the MTG-2.

13

I think you should get the lathe going and make a custom hybrid with nice selected reflectors

14

No. I'm retiring after the OL build is finished.

15

Wow…awesome flood, makes me want to have one too…. hmm I do have TR-J12 with beast driver and extra MT-G2 LED around… do you think it will work too without swapping beast driver to FET driver? :bigsmile:

16

No. It won’t work. With an MTG added, it would be like having six emitters. The KD 5*beast driver won’t run more than five. I tried it with six XML.

17

never mind… I think I do have one of those zener mod kit somewhere around, now if I remember where I put them :weary:

18

way cool. how many lumens and kcd you think your at? can it be ran for 5 mins straight on highest mode?

19

I haven’t run it for five minutes on high yet, but I expect it would be pretty toasty. It’s just a small light, but the integral pill design moves the heat to the cooling fins pretty efficiently. It has five modes, so you can knock it down a mode or two and it’s still friggin bright. Five minutes on high should take the top off the cells pretty quick.

I was going to add extra heat sinking, but I couldn’t get the head apart. Also, I wasn’t 100% sure this mod was going to work so I didn’t want to do a lot of extra work and end up with a fail. I built it just to see what would happen, a prototype.

I’m liking this light more and more. With only two cells, it’s small and portable with huge flood. Lately I’ve been working on big lights with three cells, it’s really nice to hold a small manageable light with big aspirations.