Anybody run MTG2 6V direct drive with 2 * 26650 protected or IMR cells?

Hi all,
I have a 3D Mag Lamdalights which is designed to take any 15~16mm board. I just screw it down to the copper heatsink.

I just ordered the Noctogon 16mm 6V MTG2 and was gonna run 2*26650 in the 3D Mag tube.

Has anybody ran big cells like this with MTG2 in direct drive? Just want to make sure I don't fry the LED.

Thank you,
bigC

It would appear not - but someone has to be first

Darn...there goes potentially $20 bucks down the drain.....lol

If it works, It would make an awesome mod for my Elektrolumens ST90. I'm watching and waiting

I have run an mtg2 direct drive off of two imr 18650. The mcpcb is screwed down to a copper and aluminum heat sink, with ic diamond between the mcpcb and sink. I use the light pretty regularly. I had tried to do it with protected cells but the 7.5 amp protection circuits kept tripping.

Edit: I realize you asked about protected 26650, but thought I'd offer the info about the protection circuits anyways.

Here's the thread I put together https://www.candlepowerforums.com/threads/372850

darkknightlight said:

I have run an mtg2 direct drive off of two imr 18650. The mcpcb is screwed down to a copper and aluminum heat sink, with ic diamond between the mcpcb and sink. I use the light pretty regularly. I had tried to do it with protected cells but the 7.5 amp protection circuits kept tripping.

Edit: I realize you asked about protected 26650, but thought I'd offer the info about the protection circuits anyways.

Here's the thread I put together https://www.candlepowerforums.com/threads/372850

Click to expand...

I will be running the Keeper protected ones, but the IMR Keepers are also readily available in case I get circuit tripping. I was more concerned with 26650's turning the MTG2 blue, but well see.

Protected specs
Specifications:
Nominal Capacity: 5200 mAh
Nominal Voltage: 3.7V
Discharge End Voltage: 2.5V
Max Continuous Discharging Current: 9.5A

Best of luck! I just tried a pair of Sony 26650VT. They didn't turn the led blue, but I think they were sending too much current. The output was less than with my two imr 18650. If you look at Match's destructive testing of the mtg2, there is a tipping point around 12 amps if I recall correctly where the led will continue to pull more current, but the output diminishes.

I run two protected 26650 in a mag direct drive. I haven't measured current, but the led seems happy. It is awesomely bright.

onetrickpony said:

I run two protected 26650 in a mag direct drive. I haven't measured current, but the led seems happy. It is awesomely bright.

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How do you have yours setup? I'd like the additional capacity of protected 26650s over my imr 18650s

darkknightlight said:

How do you have yours setup? I'd like the additional capacity of protected 26650s over my imr 18650s

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I cut down the factory spring, sanded the ano off the inside of the cap and stuffed the spring inside. Then some lengthwise cut sections of pvc pipe to carry the batteries. Modified the factory switch, it's holding so far. Heatsink from britelumens.

Modified aluminum reflector. It was smooth, but the beam was nasty, so I sprayed a little polyurethane on it. It came out way better than I thought it would. I also opened up the base a bit. UCL lens from flashlight-lens.com I think that's about it.

I will be removing the anodize inside of the tailcap too and cutting the stock spring.

My current host is a 3D Mag, but I am buying a 2D Mag and moving all the electronics over to the 2D Mag.

Below you can see the 16mm XML2 board.

What are the details on the head and switch you have there?

onetrickpony said:

What are the details on the head and switch you have there?

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The Aluminum head is a custom made to be a MULE.

The switch is no longer made but was made and included when you purchased a Lamdalights 3D Varapower. Lambda made the heatsink so I could swap any 16mm board later on. The switch is hand assembled by him. Its a direct drive switch with 33 modes. Simplicity but utterly useful.


bigC

bigchelis said:

The Aluminum head is a custom made to be a MULE.

The switch is no longer made but was made and included when you purchased a Lamdalights 3D Varapower. Lambda made the heatsink so I could swap any 16mm board later on. The switch is hand assembled by him. Its a direct drive switch with 33 modes. Simplicity but utterly useful.


bigC

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I was wondering if it was a mule or you had yet to install an optic. Cool.

I bet it's going to rock with the mtg2, I did a current test on mine at the led and the tail last night, 3.8 amps at turn on. I'm betting the switch and wires are the limiting factor. Either that or the forward voltage, the batteries I have settle around 3.8 volts fully charged at rest. Probably the switch though. Do let us know how it goes if you try it.

onetrickpony said:

I was wondering if it was a mule or you had yet to install an optic. Cool.

I bet it's going to rock with the mtg2, I did a current test on mine at the led and the tail last night, 3.8 amps at turn on. I'm betting the switch and wires are the limiting factor. Either that or the forward voltage, the batteries I have settle around 3.8 volts fully charged at rest. Probably the switch though. Do let us know how it goes if you try it.

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I have a Vinh Z1 zoom light fitted with the MTG2 with a driver.


I input 2 26650's and get steady 4A at tailcap with slightly more after 4 minutes of continuous use.

My concern with 2 26650's was that I would get 6~8A at tailcap and fry the LED.

bigC

bigchelis said:

I have a Vinh Z1 zoom light fitted with the MTG2 with a driver.


I input 2 26650's and get steady 4A at tailcap with slightly more after 4 minutes of continuous use.

My concern with 2 26650's was that I would get 6~8A at tailcap and fry the LED.

bigC

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You can always rig up a meter the first time you run it, but I highly doubt you'll have a problem. I'm thinking now it may be internal resistance in the batteries. I honestly don't get it. Maybe I need to test voltage while running to get a clearer picture of what's going on. I wish Cree had done the datasheet the way they did the xml/xpg. Percentages are a pain in the behind when the grid is that sparse of values.

I do have a big copper heatsink with alum fins and a heatpipe sitting here. Maybe a direct drive with no switch test is in order.

Edit: You may have wildly different results with the batteries you're using. Mine are protected king Kong from rmm/mtn electronics. Black wrap, evva label.

Sorry for not having a picture yet, but I have to report my MTG2 direct drive is a success.



2D Mag with MTG2 direct drive off IMR Keepower 26650's. I get 4.5A at tailcap for well over 35watts of power.


I can still spray Deoxit spray into the Maglite switch which increases the tailcap current by at least a 20% margin from my testing. So, not sure I want to remove the factory switch resistance.


best,
bigC

bigchelis said:

Sorry for not having a picture yet, but I have to report my MTG2 direct drive is a success.



2D Mag with MTG2 direct drive off IMR Keepower 26650's. I get 4.5A at tailcap for well over 35watts of power.


I can still spray Deoxit spray into the Maglite switch which increases the tailcap current by at least a 20% margin from my testing. So, not sure I want to remove the factory switch resistance.


best,
bigC

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That's awesome, thanks for the update. Of course, now I want some IMR's and some Deoxit spray $ ugh.

onetrickpony said:

That's awesome, thanks for the update. Of course, now I want some IMR's and some Deoxit spray $ ugh.

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Last week I built 3 Maglite Direct Drive builds for myself and family with XML2 copper board variants. All fed off 3NiMH Tenergy cells for 4.2V input.

Tailcap currents started at 1.8A to 2.2A at tailcap with all 3 builds. After just a simple Deoxit spray into the switch with the skinny straw that comes with the can; wholly crap they all net over 4A at tailcap and one of the 3 turns blue tint and now I need to add resistance to that one. lol

.... I never imagined Deoxit was that great at removing resistance.


Deoxit D5 spray is what I use. don't think the gold version is worth the extra $$$.



bigC

That is a real eye opener, did it seem to make the switches more or less durable, my biggest concern with all of these mag builds is that I'll burn out the switch. Mine is still running like a champ direct drive, no issues at all fwiw.