Redux: Mag 2C running 3x CR123A

ElectronGuru

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One of my favorite Maglite upgrades is also one of the oldest and one of the easiest. Given to me (literally) by Niteowl shortly after my arrival on CPF, this venerable mod seems to have new uses every time I turn around. Here is a primer on the basics of the setup, followed by two cool examples, one LED and one incan.


Here is the complete before and after. Start with a Maglite 2C and 1) replace both C batteries with three CR123As (or IMR16340's), 2) shorten the spring, and 3) add a tube wrapped in a pair of gaskets.

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The result is more voltage (3 -> 9 (10+ with IMRs)) and less weight (and capacity)

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First get the right tube and gaskets. This one is 7/8" (outside diameter), cut to 4" long, with gaskets just tight and thick enough to hold the tube in place.

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Everything stays centered and snug, without being difficult to remove. When they're thick enough, the gaskets have a tendency to roll down when inserted, so role them toward the top before installation.

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Then comes the tricky part, shortening the spring. New ones are cheap, so messing up isn't a big deal. Its also very easy to convert a light back and forth and move the mod parts between different lights. Bolt cutter your way through or get two pairs of pliers. Put them on either side of the breaking point, then bend back and forth until the pot metal gives up and seperates. Leave about 2/1/2 turns and then center the last half turn so it makes broad contact across the smaller (-) on the new cells.

2ef2s9g.jpg



Then you're ready to load er up. Here's a fun incan configuration (incan-tation?). 3xIMR16340 + Fivemega bipin adaptor + WA1331 bulb. Result: about 800-900 lumens of near white color (vs 200-300 for the original 2003 version). This just in, 1331 bulbs are marked for death.

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Here's a fun LED config. An exotic TerraLUX (if there can be such a thing) that normally requires longer/heavier Mags to function.

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:devil:
 
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jaundice

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Electronguru;

What's the ID of the tube? Also, exactly what sort of tube are you using? It looks like some sort of poly tubing? I've tried this with some heater hose, but it was too thick. I also tried some plastic tubing, but it I had trouble with it binding on the inside of my flashlight.

Thanks,

-John
 

elumen8

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Thanks for bringing back good memories. My very first mod of any sort was the Mag 2C loaded with three CR123s and a 5-cell Magnum Star Xenon bulb. Just a simple little mod, not the brightest in the bunch, but it got me started.

JB

btw..it wasnt even that long ago :sssh:
 

supasizefries

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Very very cool. I recently just bought a 2C to start modding it. I've got a couple of 2D builds under my belt but I absolutely love the 2C form factor.
 

Niteowl

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Electronguru;

What's the ID of the tube? Also, exactly what sort of tube are you using? It looks like some sort of poly tubing? I've tried this with some heater hose, but it was too thick. I also tried some plastic tubing, but it I had trouble with it binding on the inside of my flashlight.

Thanks,

-John

The tubing is a flexible, polymer pipe Sold as "Flex-Pex" where I bought it. It's used for plumbing in place of rigid pipe. A straight five foot section was about $5.

The ID is roughly 16.5mm or 21/32" (just over 5/8"). OD is roughly 22mm or 7/8".

Nice tutorial on a quick and easy mod sure to bring a smile to the face to those trying it for the first time. And as ElectronGuru shows, it also has uses for those deeper into the hobby.
 

jaundice

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The tubing is a flexible, polymer pipe Sold as "Flex-Pex" where I bought it. It's used for plumbing in place of rigid pipe. A straight five foot section was about $5.

The ID is roughly 16.5mm or 21/32" (just over 5/8"). OD is roughly 22mm or 7/8".

Nice tutorial on a quick and easy mod sure to bring a smile to the face to those trying it for the first time. And as ElectronGuru shows, it also has uses for those deeper into the hobby.

Interesting. My intention was to use 18650s, which, of course, are wider than 16340s. It looks like this mod is geared specifically to 16340s. Perhaps that's my problem.

-John
 

ElectronGuru

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The tubing is a flexible, polymer pipe Sold as "Flex-Pex" where I bought it. It's used for plumbing in place of rigid pipe. A straight five foot section was about $5.

Thanks for chiming in! :thumbsup:



My intention was to use 18650s, which, of course, are wider than 16340s. It looks like this mod is geared specifically to 16340s. Perhaps that's my problem.

Yes and no. The basic principal here is to use a tube + gaskets to reduce the diameter of the battery tube. Without the gaskets, the OD has to precisely fit and even if it does, its a pain to remove. This "new" approach can be scaled as far as parts can be found or made to make it work. Bring your light and batteries to the nearest home center and experiment. Find a tube with an ID that works for the cells but still giggles around in the light. Then find gaskets to hold the tube steady inside the light.

But keep in mind that 18650's are longer (30mm for two), so you'll need to modify the tailcap more. Here's an elegant solution (click the photo to see more):


 
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Justin Case

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This thread shows another make-shift sleeve made from readily-available materials to fit 18650s in a C Mag. Use Orbit 1/2" x 24" Flexible PVC Pipe available at Home Depot hardware stores.

If you combine this with FiveMega's Wide/Deep Tailcap, you should be all set to run a 2C Mag using 2x18650.
 

supasizefries

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Electron Guru: I'm assuming the tail has been de-anodized and the spring has been cut to fit 2 18650's? If so, I'm all over this!! :crackup:
 

ElectronGuru

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That photo (forgot to say "click it") is from Mirage Man. I think he did a bit more than remove the anno. This particular setup is also in cool in that it also works for AW black C's.
 

sdlotus

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Thanks for all the tips guys.Even i was able to do a 3 cr123s in a 2 c mag.Love it .Now i want a bulb adapter and try other bulbs.How can i get the adapter and bulb.Thanks everyone..................stanley
 

ElectronGuru

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lctorana

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Another alternative, and one I am very fond of, is to do the 3xCR123A design, but use 2x18500 cells instead.

This give exactly the same voltage (about 7.2-7.4V under load), double the capacity and is reachargeable to boot.

And a 18500 cell is almost a bullseye match for a C cell for length.

You don't even need a pipe. Wrap the two cells laid end to end in about three turns of thick cloth, and you're done. The batteries are centred and cushioned. The cloth stays in the torch when you drop the batteries out, which is a useful feature.

The versatility of this mod, bulb-wise, is amazing:

7.2V argon bulb (eg PR18)
7.2-7.6V krypton bulb (eg KPR118, LWSA601)
7.2-7.6V xenon bulb (eg HPX60, LMSA601)
6V krypton bulb overdriven (eg KPR112, LWSA501)
4.8V krypton bulb massively overdriven (KPR113) - for the brave
Pelican 3804
Pelican 3853L, 3854L, 3853H, 3854H ("RoP" if you use metal reflector, glass lens and IMR cells)
1111, 1274, 1164, 64250 with bi-pin adaptor (ditto)
HPR71, GH24 - RoP-low competitors

It all depends upon how many lumens you want. Note that the first five on the list can be safely used in a cheap plastic throwaway 2C torch.

(I wouldn't stress 18500 cells, even IMRs, with really high-current bulbs like the 5761. That's when you bore out for 26500s.)
 

jaundice

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Guys;

Tonight I was working on making a mag 2D to 2x18650 conversion with PVC pipe and couplers, and I almost had an AW 18650 go high order on me!

Here's the thread: https://www.candlepowerforums.com/threads/236834

I appreciate your input. I'm new to flashaholism, so I want/need to learn from those more experienced than me.

I'm grateful that I spent a couple hours on "Smoke and Fire, Hot Cells and Close Calls" forum when I first got into LiCO cells, so I recognized the warning signs and took immediate action. From working in public safety in the past, I know to have appropriate fear and respect for what I generically refer to as "methyl-ethyl death" -type chemicals.

-John
 

sdlotus

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Thanks electron guru for the info for parts.Can't wait to order them and try them......................stanley
 

^^Nova^^

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I was thinking along these lines only a few days ago, but with a D mag.

Is it possible to fix 3 CR123's abreast in a D mag (similar to the 3AA-2D adapters)? I was wondering about three parallel stacks of 3 CR123's in a 2D to run the 3854L bulb. If it doesn't flash the bulb, there should be over 4000mah of capacity with a long shelf life. Perfect standby torch.

Cheers,
Nova
 
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