why no mt-g2 in small 18650s?

caddylover

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I have a mule built by vinh that has 4 of them, it won't even turn on with two 18650's fully charged. I'm waiting for my 26650's to come in the mail. Next month, Niwalker will have the MM15 which is a smaller light with two mt-g2's in it.
 
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hoop762

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I have one of vinhs mt-g2 p60 drop ins. You can run it on a pair of imr 18350s in a p60 host. Won't get much run time, but that's a pretty small package compared to other mt-g2 options out there.

I run mine in a extended solarforce host and 2 18650s.

I don't see them being mass produced as a factory model. More like customs or limited-runs. But then again, I don't know much about much.
 

Canuke

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At small 18650 form factors, either you're using IMR's and you have a duty cycle with all that heat, or you're running them at low enough current that you're well within the XM-L performance envelope anyway. I have two 2s direct-drive mods with MT-G's in large Defiant hosts (2x18650 and 2x26650, non-IMR), and while they blow my XM-L's away, they also dump quite a lot of heat, even for these fairly chunky hosts.
 
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mattheww50

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.I tend to look at the problem from a 'power' perspective. Full output on a MT-G2 emitter requires about 25 watts at the emitter, so the cell would need to be able to provide something north of 25 watts to power such a light. The limit for the typical 18650 is in the 10-12 watt range (protection kicks in if you get much past that), which accomadates a XM-L2 at close to maximum output. It might be possible to build a single cell MT-G2 light using an IMR cell, however as others have pointed out, the run time would be quite short, and heat dissipation for the MT-G2 would be challenging to put it politely. I suppose you could add a tiny fan to help, but that requires still more power to run, and result in an even shorter run time. .
 

dss_777

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Wait no more. If you consider a functional hand-held light using 2x18500 as within the "small" form factor, look at the new Malkoff Wildcat.

From the Malkoff website:

This is the Malkoff Devices Warm HCRI "Wildcat" head. This flashlight produces 1000 (measured) Out The Front Lumens at turn on and 800 (measured) continuous Out The Front Lumens. The Flashlight has a 27 degree beam. It is a flood type beam. The Lux is 2300 at one meter. This is a real room/warehouse lighter. The LED is a 3000K Cree MTG2. It will easily light objects at 150+ feet. It has a High/Low function accessed by head rotation. The low output is approximately 80-100 lumens depending on batteries used.

It can use 3-4 CR123 lithium primary batteries or two rechargeable 18500 batteries (MD3 body) or two rechargeable 18650 batteries (MD4 Body) lithium ion batteries (use protected cells only). The runtime on high is approximately 1 hr 15 minutes minutes with two 3400 mah 18650's. Three CR123 primaries will only provide about 15-20 minutes of continous full output due the batteries inability to provide current and maintain voltage. Four CR123 primaries will provide about 45 minutes full output runtime.

Discussed in this thread: http://www.candlepowerforums.com/vb...w-Malkoff-1600-Lumen-Wildcat-beam-shots-added!!
 

alpg88

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why no mt-g2 in small 18650s?

pbly for the same reason there is no v12 subcompact car
 

Fireclaw18

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Mar 16, 2011
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I modded a Sunwayman C20C with an MTG2.

The Sunwayman C20C is a relatively small single 18650 light. It's smaller than a Zebralight SC600. The driver I used maintains modes and can ramp up and down. Works pretty well actually. I'm running it at 3.04 amps on two IMR 18350 cells.

The result:
(1) VERY bright. Probably around 1700 lumens out the front. Should be around 2100 at the emitter. Amazing output for such a tiny light. Much brighter than comparably sized XM-L2s. Brighter than an XM-L2 at 6+ amps on copper, but with less throw.
(2) VERY floody beam. The emitter is HUGE compared to the size of the small orange peel reflector I'm using. The beam is enormously floody, but does have a very wide hotspot. Point this at a wall in a house from close range and the entire wall lights up. However, for distance viewing it doesn't have much throw. My much smaller modded 3.04 amp XTAR Wk42 with a single XM-L2 has significantly more throw.
(3) BEAUTIFUL tint. MTG2s always seem to have awesome tints. Very pleasant neutral white.
(4) Heats up very fast. The head of this light gets hot fast. Not as fast as my other modded C20C (triple XPG2 with FET driver, pulling around 7.4 amps), but still fast enough that it becomes too hot to touch comfortably after about 1 minute at max. Runtime at max power with my IMR cells should be about 15-16 minutes, but the light would burn up from overheating long before then.

I think you aren't seeing MTG2s in small form factor in stock lights because
:
(1) they require 2 cells in series or some kind of boost driver,
(2) the cells required are IMR 18350 or maybe IMR 16340, which aren't as nearly common as 18650, limiting the market.
(3) don't really take off till around 3 amps which limits performance on small lights due to limited battery size,
(4) produce a very floody beam, due to the very large low-luminance LED die.

XM-L2 seems more optimum for such a small light.
 
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