Surefire M3LT KX9T: Modding Options?

SYZYGY

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Sep 6, 2019
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304
apologies if this is posted in the wrong area.

i've got a Surefire M3LT CombatLight with KX9T head.

very awesome looking light imo. nice shape, machining, and anodization. big, BEAUTIFUL (fresnel?) optic. wow.

surefire-M3-LT-KX9-T-fresnel.jpg


surefire-M3-LT-KX9-T.jpg


surefire-M3-LT-KX9-T-components.jpg



i hate that it takes 123A primaries. i hate primaries unless it's an emergency-only light.
the other issue is that the emitter tech is a decade old.

as-is, this light is sadly not very useful to me. what modding options are there?

my wish list:

  • ideally, i'd love to somehow get it to take 18650 (or better yet 21700) batteries.
    • can the body be bored wider? looks a little skinny, idk.
    • are there wider battery tubes? maybe something aftermarket? bonus if it doesn't cost much.
    • as a last resort, can any rechargeable (smaller) batteries be used without heavy modification to the existing battery tube?
  • i'd also love to crack the head open and get a newer emitter in there.
    • what are my options for this? i don't know much about emitters, but i can read datasheets and am comfortable with hot air rework and stuff.
    • are there any emitter modules available? maybe i'll need a new driver, too.

any other worthwhile mods?

i'm not totally sure, but it seems like the head can be cracked open where i have the red arrow pointing.
i found this thread: https://www.candlepowerforums.com/vb/showthread.php?427361-Surefire-M3LT-S-KX9T-S-LED-mod
but the pics are long gone. sounds like there's some glue that needs to be softened with heat. i'll try hot water, and if that doesn't work, i'll try progressively hotter temps with my heat gun.

any guidance would be much appreciated.
 
Last edited:

marcdilnutt

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It can be bored out to 18mm be t as it is a 3 cell light it is only big enough for 1.5 18650s so you would need to find 18500 cells. It can currently fit 16500 or maybe 17500 cells. I am not sure about where that head opens but Surefire loctite is notorious, you may need a heat gun and strap wrench to get it open. Good luck!

Sent from my [null] using Tapatalk
 

altermann

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I did the mod of the same head
It's not so easy to disassemble
Have it available for sale or trade
 

SYZYGY

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Sep 6, 2019
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304
I did the mod of the same head
It's not so easy to disassemble
Have it available for sale or trade

haha yes it appears to be solidly on there :)

any tips? if you don't want to share the secrets or whatever, i respect that, it's just that i like to re-use existing parts whenever possible so as not to create waste. especially when the parts are nice.

the heat sink fins thankfully have square sides, so i was going to chuck the head up in a vise and then heat the bezel with a temperature-controlled heat gun. i'll experiment with heating some cured loctite first to see what kind of temperature range it might soften at. although i wonder if in reality the better approach is to quickly heat the exterior with a high temperature so you don't transfer too much heat to the fresnel optic like you would by heating the whole thing slowly at a lower temperature. hard to say without experience.

but could you at least verify that it's threaded (in the conventional sense -- clockwise tight, counterclockwise loose) and not press fit? much appreciated.

also, can you please tell me where to look at your offerings for this light? or pm me? depending on price, i may just treat myself to the finished product. or if i ruin mine. thanks!
 

michaex

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Nov 28, 2019
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In terms of body, you could try M6 or bored M4 for greater capacity. That will make it another light though :)
 

Modder

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did you get to modding this light or even get it open ?
if not I can give some tips and instructions…
 

foxtrot824

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Sep 24, 2008
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The 02135!
Sorry, been away for a long time. First off I can second fivemega's recommendation, I run a 2x26500 on one of my mods, I love it.

Looks like you have won half of the battled getting the head off the M3LT host, the top also unscrews as shown in one of your pictures. You'll want to take it easy on the heat there because sometimes there is a thin diffuser that will melt easily.

I have done this mod 3 times, twice were a success... so proceed at your own risk.

Once the front of the head is exposed you can see the LED board easily, mine were XM-L footprints (5x5), depending on what you wanted to put in you could try and reuse that board or just glue in a star board.

On the electronics side, you can just pop off the black thing that holds the springs and that will reveal the driver. I swapped mine to be a 2 mode driver for the XHP70.

Below are some KX9 and M3LT head picture. The xray of the KX9 should give you an idea of how things are sandwiched together.

https://ibb.co/XYmrY0j

https://ibb.co/X4pZkkZ

https://ibb.co/sFZVpvz

https://ibb.co/XzJzQmK
 
Last edited:

badtziscool

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Oct 13, 2006
Messages
1,722
Wow. Nice seeing your post again foxtrot! It's been a while.

Sorry, been away for a long time. First off I can second fivemega's recommendation, I run a 2x26500 on one of my mods, I love it.

Looks like you have won half of the battled getting the head off the M3LT host, the top also unscrews as shown in one of your pictures. You'll want to take it easy on the heat there because sometimes there is a thin diffuser that will melt easily.

I have done this mod 3 times, twice were a success... so proceed at your own risk.

Once the front of the head is exposed you can see the LED board easily, mine were XM-L footprints (5x5), depending on what you wanted to put in you could try and reuse that board or just glue in a star board.

On the electronics side, you can just pop off the black thing that holds the springs and that will reveal the driver. I swapped mine to be a 2 mode driver for the XHP70.

Below are some KX9 and M3LT head picture. The xray of the KX9 should give you an idea of how things are sandwiched together.

https://ibb.co/XYmrY0j

https://ibb.co/X4pZkkZ

https://ibb.co/sFZVpvz

https://ibb.co/XzJzQmK
 
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