Smallest 18650-powered light?

I was doing some eyeball-measuring, and I started to wonder why there aren't more smaller 18650-power lights out there. I like my M1 Hunter and all, but If there is a simple 2-stage Fenix-like twisty and a shallow flood-type reflector with very little if any hotspot, I can't see any reason why you couldn't make an 18650 light around the size of a Lumapower M3 when it's in 1x123a configuration.

Is there the demand for a light like that out there? I remember seeing CAD designs for something similar but never a real light. It would be very nice to have 18650 runtime in that size package or a tad larger...

Anyway, if you know of a small 18650 light, please post about it!

MUSING: I wonder if it would be possible to simply make a new body tube and use the head assembly from a Fenix P1D-CE... if I'm right, it should be possible to make one that comes in at around 10.4cm long... just 1.1cm longer than the M3 in 1x123a mode...

Daekar said:

I was doing some eyeball-measuring, and I started to wonder why there aren't more smaller 18650-power lights out there. I like my M1 Hunter and all, but If there is a simple 2-stage Fenix-like twisty and a shallow flood-type reflector with very little if any hotspot, I can't see any reason why you couldn't make an 18650 light around the size of a Lumapower M3 when it's in 1x123a configuration.

Click to expand...

I think a light like that would be great. A 18500 twisty would be even better -- it would be the same length as a regular AA flashlight, just slightly thicker. I think the only thing from Fenix that comes close to what you're looking for is the Fenix P3D, running a 17670 LiIon cell.

2xTrinity said:

I think a light like that would be great. A 18500 twisty would be even better -- it would be the same length as a regular AA flashlight, just slightly thicker. I think the only thing from Fenix that comes close to what you're looking for is the Fenix P3D, running a 17670 LiIon cell.

Click to expand...

Darn! Well I guess I could try boring out the body of a P3D to accept an 18650... what do you figure the chances of that are?

Modding a Ristoft light with an 18650 makes a very compact light, its dimensions are nearly identical to the Elly (1 AA light). The head is a little wide, though you could lathe it down if you really wanted to, also the Elly head fits the light and might be a hair narrower. The Ristoft is about an inch shorter than other 18650 lights I've seen, though the barrel could be a little narrower since it is originally a 3 AAA carrier light.

I think a simple small twisty 18650 would be really cool and a FANTASTIC combination (A "super" pocket light). I think someone like Peak should make a version. I like the Peak lights with "pocket" body since they are really small and compact. Keep the battery tube and head at the same diameter using a 17mm reflector and SSC LED.

Drive the LED at around 500ma and you would get a very nice bright light with excellent runtime. The emitter would be operating in a nice efficient range with plenty of output and the 18650 battery could supply this for at least 4 hours in a constant regulated mode. This could be built relatively cheaply. I'm there. I already have a great charger and several 18650 batteries.

With this kind of runtime you would not need to lower output to extend runtime. Having a low output and a higher ouput would just be icing on the cake.

A compact twisty with a flood beam and a 4 hour rechargeable battery would be fabulous. I could see this thing selling like hot cakes.

Even a Leef 18650 body for the P1D-CE would be a hot seller if it could be done.

LightScene said:

A compact twisty with a flood beam and a 4 hour rechargeable battery would be fabulous. I could see this thing selling like hot cakes.

Even a Leef 18650 body for the P1D-CE would be a hot seller if it could be done.

Click to expand...

Are you reading this, modders? If I had access to a lathe I'd be warming it up right now... sounds like this is an unfilled niche in the flashlight ecosystem...:naughty: I'm really hoping that somebody will at least offer a P1D-CE body. If you were to go the complete-light route, my guess is that a 2-stage light would sell better than a 1-stage... and you could have a truly "low" low, and... well, 500ma sounds good to me for high. It wouldn't be a firebreathing monster, but it would be practical.

One question though - do the P1-CE and P1D-CE use the same stock body? I ask because if someone makes an 18650 body for one it would be nice if it would fit the other as well... that way the people who bicker about whether or not you need multiple settings on an EDC light could BOTH buy the body, not just one or the other.

Daekar said:

Darn! Well I guess I could try boring out the body of a P3D to accept an 18650... what do you figure the chances of that are?

Click to expand...

Sorry to pop you balloon but there is no space in the stock P3D body to accept a 18650, even a 17670 is a hard fit for the stock body...

Custom body is another story :devil:


Pablo

PEU said:

Sorry to pop you balloon but there is no space in the stock P3D body to accept a 18650, even a 17670 is a hard fit for the stock body...

Custom body is another story :devil:

Pablo

Click to expand...

I believe Daekar is thinking about boring out the stock tube. I doubt it but could anyone confirm the thickness of the stock tube?

PEU said:

Sorry to pop you balloon but there is no space in the stock P3D body to accept a 18650, even a 17670 is a hard fit for the stock body...

Custom body is another story :devil:


Pablo

Click to expand...

Yeah, I was talking about boring out a P3D body... but that would be a half-baked solution at best... because it would still be bigger than it should be. I would only do that if I couldn't figure out anything else... which leads me to my next problem:

Does anybody know the thread spec for the P1D-CE and P1-CE? Can't make or get a body made without that information...

Daekar said:

Yeah, I was talking about boring out a P3D body... but that would be a half-baked solution at best... because it would still be bigger than it should be. I would only do that if I couldn't figure out anything else... which leads me to my next problem:

Does anybody know the thread spec for the P1D-CE and P1-CE? Can't make or get a body made without that information...

Click to expand...

The inner diameter is 17.10mm, the lowest external diameter in the body is 18mm, that gives you 0.45mm wall, you can fit a 17670 if your battery is under this diameter, most AW don't fit or fit under pressure making the unit difficult to use. Thread pitch is 0.75mm

I won't bore a stock body unless you can do with precision, you can end with the threads in one hand and the rest of the body in the other...


Pablo

Well, that decides that - no boring the body. That means a custom body looks like the only way to do it. Thanks for the thread-pitch measurement, PEU! I'm trying to figure out what kind of tap to buy to create the threads of the ID of the body tube... do you know the ID and OD of the threads? Or if they're a standard size?

Or... PEU, if you're in the mood for another project now that Lumapower is selling D-mini 18650 tubes... this sounds like something similar that might be a good replacement!

I would 100% buy a LEEF style 18650 body ("Leef with McClicky" like the P1D version), or even a 17670, AND a CR123 body for the L1D/P2DP2D head if offered. I love my P1D Leef - it is one of the only Fenix I use regularly. I'd prefer the P2D UI with the two mode twist head with low first, then med, then high.

Pleeeeeeeeaase make it! And it must be black HA ano.

Daekar said:

...I'm trying to figure out what kind of tap to buy to create the threads of the ID of the body tube... do you know the ID and OD of the threads? Or if they're a standard size?

Click to expand...

I measure 19.32mm ID in the head threads and 19.82 OD on the tube threads.
Keep in mind that they are not the tightest threads, so this may not tell you a lot.

i remember this beauty, its light no. 2 in the list ...... nice !!!

https://www.candlepowerforums.com/posts/2019297#post2019297

Man that #2 is cool. Does anyone have something like this? How much did that cost?

What about the Electrolumens DeCree, 4.375" (111 mm) 185 lumens and cheap to boot.......

PEU said:

The inner diameter is 17.10mm, the lowest external diameter in the body is 18mm, that gives you 0.45mm wall, you can fit a 17670 if your battery is under this diameter, most AW don't fit or fit under pressure making the unit difficult to use. Thread pitch is 0.75mm

I won't bore a stock body unless you can do with precision, you can end with the threads in one hand and the rest of the body in the other...

Pablo

Click to expand...

So this one can't be bored. Thanks.

If you worry about precision, try an adjustable hand reamer. Like this one.
Cheap yet precise. I know a guy hand bored a 6P for use with 18650. The result is great. The only thing he complained was sore hands.

oops