2D mag to 18650?

Mr. Nobody

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Is there an option to use another type of batteries in the 2D maglite ? D batteries are kinda expensive and I only use rechargeables in my home and the last item that needs rechargeables is the 2d maglite. I would like to use 18650s but if that isn't an option than what is ? I use a nitecore d2 & d4 so would like to use something in the maglite that the chargers can charge.

Any help and ideas would be greatly appreciated:thumbup:
 

alpg88

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there are many options, 18650 are used in mags quite a lot, on this and other flashlight forums. you can use 2x18650 in your 2d mag along with 6cell bulb. i've done it many times. that is if you want to keep it as close to stock as you can. if not there are dosens of different light sources that can be used in mag.
 

Chicken Drumstick

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Is there an option to use another type of batteries in the 2D maglite ? D batteries are kinda expensive and I only use rechargeables in my home and the last item that needs rechargeables is the 2d maglite. I would like to use 18650s but if that isn't an option than what is ? I use a nitecore d2 & d4 so would like to use something in the maglite that the chargers can charge.

Any help and ideas would be greatly appreciated:thumbup:
It is certainly possible, but it also depends on what you want to achieve overall.

Remember a D cell = 1.5v while an 18650 is 4.2v, that's quite a difference, so you can't just use the same bulb with 18650's.

I have a couple of 2D Mags that I run 2x26650's in. Very easy mod, just trim the tailcap spring down as the 26650's (and 18650's) are longer and bend the end over a little to make contact with the battery. No other modes and it will work. 26650's don't even rattle too much, although you could easily make a battery tube spacer from plumbing tubing, wood or even cardboard.

18650's will probably need something to keep them in place as they are narrower. Although personally I think a 2D is physically way too big to just use two 18650's in. 26650's will give more runtime and means you aren't just carrying around a mostly empty bit of aluminium tubing with you.

2x Li-ion = 8.4v so you can then run a bulb from a Mag that uses more D cells. A 6 cell or maybe even a 5 cell D Mag bulb.

Or other cheap upgrades are a simple LED drop in for the correct votlage. The Torch Site in the UK sell these, they look like a normal bulb and fit like the standard bulb does, only they have a driver and LED where the glass bit would normally be. They are not the most powerful, but will totally transform an old Maglite.

http://www.thetorchsite.co.uk/TTS-3WCR90_Maglite_CNC_Fit.html


Of course you could just run rechargeable D cell batteries if you have a charger. But they aren't the cheapest. You'd also want to make sure they were Low Self Discharge ones, else they'd go flat in a couple of weeks of storage. And last up, there are plenty of 1, 2 or 3AA to D cell converters about. So you could use Eneloops in these. An AA doesn't have same capacity as a D cell, so that's your trade off, but a quick simply and easy mod. Although again I feel if you use a 1AA to D converter, you are not really gaining anything over a Mini Maglite (throw due to the reflector size). But it makes for a big heavy torch vs ability.

3AA to D will at least give reasonable runtime. Remember if you want to retain the same voltage you'll want parallel adapters.

Series adapters will up the voltage. But would give options to run different LED setups or higher powered bulbs. e.g. a 3AA series adapter would give you 6 x 1.2v with Eneloops (7.2v) which is enough to power a fairly beefy hotwire incan Mag setup.
 

Mr. Nobody

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Hmm I ordered 2 of those plastic D holders that use AA batteries. My 2d maglite uses a LED (aftermarket) and it is not very bright. I just tried a single 18650 on it and its 5x brighter than when using the 2d batteries. Now my question is if I run x2 26650s will my LED last ? Its the 180lm drop in (looks like a normal bulb but has led). Not a malkoff circuit drop in like I wanted back in the day. To me the D battery is just outdated lol
 

otis311

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Like already stated it is fairly simple. Make an adaptor tube out of PVC pipe (3/4" if I'm not mistaken). I like to use grey electrical conduit and couplers. For the spring I heat up the big coils and bend them smaller to fit inside the end cap. You then need to remove the anodizing in the end cap for the spring the make electrical contact.

 

alpg88

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Hmm I ordered 2 of those plastic D holders that use AA batteries. My 2d maglite uses a LED (aftermarket) and it is not very bright. I just tried a single 18650 on it and its 5x brighter than when using the 2d batteries. Now my question is if I run x2 26650s will my LED last ? Its the 180lm drop in (looks like a normal bulb but has led). Not a malkoff circuit drop in like I wanted back in the day. To me the D battery is just outdated lol

hard to say since we do not see the specs of the led, but lets assume it is 2-6cell bulb, than 2 26650 would not harm it, since it is within specs, however if it is a bulb type mag drop in, that it has very poor heattransfer capability, so that means teh brighter it burns, the hotter it gets, the more it degrades, the less it will last. it would last a lot longer being driven by 2 alkaline D cells, since it is running cooler, but light output will be a lot weaker, as you already noticed. that type of bulb is prbly the worst type of drop in heat transfer wise, made for mags.
 

Mr. Nobody

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Like already stated it is fairly simple. Make an adaptor tube out of PVC pipe (3/4" if I'm not mistaken). I like to use grey electrical conduit and couplers. For the spring I heat up the big coils and bend them smaller to fit inside the end cap. You then need to remove the anodizing in the end cap for the spring the make electrical contact.

Nice OK I'll build a host for 18650. Maybe ill make just a host for a single 18650 for this bulb and on my other 2d mags ill make a host for two 18650s and find a more suitable cost effective drop in for it.
hard to say since we do not see the specs of the led, but lets assume it is 2-6cell bulb, than 2 26650 would not harm it, since it is within specs, however if it is a bulb type mag drop in, that it has very poor heattransfer capability, so that means teh brighter it burns, the hotter it gets, the more it degrades, the less it will last. it would last a lot longer being driven by 2 alkaline D cells, since it is running cooler, but light output will be a lot weaker, as you already noticed. that type of bulb is prbly the worst type of drop in heat transfer wise, made for mags.

Yup its a simple drop in I bought like 5± years ago at fry's electronics for $20.00 l. At the time I didn't think it was necessary to spend the $75 for the terralux drop in that is much more shnazy at the time. I also didn't own lights smaller than a pocket knife that puts out 1000lumen. Lol now that I own some sick small lights that can blind you from 100+ feet away, I figure why not upgrade the maglites output to something less laughable.
 

otis311

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Here is what the tail cap will look like, or similar. I like to solder pennies on them but you could probably just bend the tip of the spring to make contact with the battery.

 

Mr. Nobody

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Here is what the tail cap will look like, or similar. I like to solder pennies on them but you could probably just bend the tip of the spring to make contact with the battery.


Got more pics ? Where does that penny make contact...I could see it hitting the wall and causing a short ?
 

kyhunter1

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Send cpf member vestureofblood a pm and he will make you a very nice adapter for the 2d mag for 18650 use. He does quality work at a reasonable price.


Sent from my iPhone using Candlepowerforums
 

Chicken Drumstick

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Got more pics ? Where does that penny make contact...I could see it hitting the wall and causing a short ?
It won't hit the "wall". The inside of the tube is anodised and is the bit that connects to the tail cap anyhow, so is also the negative end.

BTW - while these look nice, you really don't need to go to this effort. Just cut the top 1/3 or so off the spring, leave it sitting in it's default position and bend the now top of the spring to the middle. It'll work just fine.
 

otis311

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Got more pics ? Where does that penny make contact...I could see it hitting the wall and causing a short ?

The penny is soldered right to the spring. I put a blob of solder on Lincoln's face to contact the negative terminal of the battery. I use older solid copper pennies. There is really no worry of short circuiting because: A, it doesn't hit the wall and B, like Chicken said that whole end of the light is negative anyway.
 

Mr. Nobody

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The penny is soldered right to the spring. I put a blob of solder on Lincoln's face to contact the negative terminal of the battery. I use older solid copper pennies. There is really no worry of short circuiting because: A, it doesn't hit the wall and B, like Chicken said that whole end of the light is negative anyway.

Gotcha. I like the idea. I'll have to try that. I would rather solder on the spring then try to bend it.
 
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