What would you say about making this light for 6xAA configuration? The idea is add an extension tube and use two parallel connected 3AA battery holders. This will add many benefits to this great light. (review, review2, review3)
= half current drain per battery
= runtime performance will be better than with best currently available 26650 liion
= even alkaline AAs could be used for full power (but nimh will still do much better of course)
= double the runtime (more than double at higher currents as we know AAs can sustain >2.8amps only shortly, 1.4amps will stand much longer)
approx. 1:10 hour on full 2.8amps with eneloops (according to eneloop.info), or even more with better batteries, with eneloops XX I would estimate about 1:30h on 2.8Amps, (then voltage falls below 1.2V per cell)
Assume this configuration for comparison: AA eneloopXX 2400mAh, currents H-2.8, M-0.8, L-0.1
Then for 3xAA runtimes are:
low- 24h
med- 3h
high- about 10min?, then output starts decline
Now runtimes for 6xAA:
low- 48h
med- 6h (300lm for 6h, not bad!)
high- 1:30h (estimated)
As far as I know the extension tube for C88 does not exist, also I don't know of any other budget lights with 6AA config.
So I started looking whether it would be possible to make it with reasonable price and this is what I have: if there will be enough interest - lets say at least 20 people would like to buy, I could get this extension tube built for approx. 12eur/ $15 + shipping. The material used would be aluminum 6060 T6, black anodization. (about anodization I have to note that I'm not sure it will 100% match the black finish of the flashlight, but black - should be very close)
The extension tube will add about 5,5cm (2.2inch) in length, so new length would be about 20cm (7.9inch)
Battery holders can be purchased cheap for example here, or here. It would be very easy to mod them for this use, just correctly glue two together and correctly! link with 2 wires. I can add pictures when my holders arrive.
So anyone seriously interested in this extension tube, please leave a note! As soon as we are 20 at least I'll make the order. For me +1, 19 more needed
Please feel free to post any ideas, advices..
jamio
I had no time yesteday to make a picture, so I'm adding now> it's not real yet, just paintbrushed/gimped how I see the flashlight will look with the extension tube.
I love that idea!
-Garry
Interested but would it require a driver swap also?
It absolutely would. The Nanjg driver is only rated to 6V and even at 6V they get very hot as well as inefficient since they can only burn off the excess current as heat. You’d need a proper buck driver rated to at least 8.4V-9V and finding one in the proper 17mm size that will output 2.8A-3A is nearly impossible. The closest in size would be 19mm AFAIK. Now, in addition to a driver swap you need to fabricate a new heatsink to go with it or at least figure out how to mod the existing one to accommodate the larger driver.
Won't be as simple as adding an extended battery tube I'm afraid. 
I think you'd be better off modifying the battery holders in such a way as to place the 3AA carriers in parallel. Not a piece of cake, but I don't think it's too hard.
-Garry
Then you will need to make it longer to fit 3 carriers (3p3s) instead of 2. Much easier but much longer. I’d just mod a Maglite at that point.
True, I didn't think of that, although it's hard for me to picture this without sketching it out or laying out the actual carriers. Ok, well just add 2 extensions (or one long one) and throw in 3 C's or 3 D's! Yes, at that point the Maglite sounds like the way to go. Besides, this host is too expensive to do so much extra modding too.
-Garry
No, no driver swap will be required! Nanjg driver is one of advantages of this flashlight, it have to remain 
As both battery carriers will be connected in parallel, voltage stays at 3.6V, capacity will double and current draw from each battery will be half >> runtimes comparison are in #1 post. Nothing else will be needed just the extension tube and DIY battery holder. Here is the picture how the holder will be made:
I agree with this, in case of 3 carriers 3p3s I would also rather mod Maglite.
Nice work. Should work very well. I always over think things. 
Or........
Buy a spare battery holder, keep three fresh AA's in it.
When the torch's batteries run low, swap it for the one in the light.
Problem solved. No custom parts, no wiring, no soldering.
Same result.
Umm . . . not if the stats in the O.P. are correct:
Look at the runtime on high comparison.
-Garry
Once you go to all that trouble (And cost), you might just want to get a member in the US, to send you a maglite. A 2D maglite will take the holders and you can have a 6AA that way. You would also be able to have a good sized heatsink too. It's just a suggestion. A 2D incan Maglite is $15USD and it should take another $15 to send. $30-$35 versus the cost of a C88 + an extension.
Also, those battery holders have a lot of resistance in them. If possible, it would be better to "make a home made holder for 6AA", or at least replace the cheap tin with copper and use gold plated springs.
It's a fine idea and I'm not saying it isn't a good idea. I'm just giving my thoughts on it.
Should be about the same, at least with eneloops. With primaries, you will get sag with three that you may avoid with 6, I agree.
I think the big advantage is sustaining the 2.8A output for much longer time (since you're only drawing 1.4A off the cells).
-Garry
I agree, and even more so if using alkalines. I just put a nanjg105c (1.4A) in the tractor supply 3xAA and run time with utilitech alkalines is nowhere near what I calculate it should be (from test discharging utilitechs at 1A w/ hobby charger). I guess they can't hack the ~40% higher rate as well as I'd hoped.
Anyway, if you wanted to make 2 battery holders (3S) into one that's 2p3s, it might be easier if you ditched the metal contacts on one end of both, epoxied the two into one and then made the appropriate connections.
anyway, Jmac is right, buy a 2D mag - I saw 2D and 3D on clearance at tractor supply this week (available in store only but listed on website).
About this mod vs. Maglite - if we consider modding maglite with XML there is this excellent mod made by jayrob on CPF, which I like very much. What I want to say is that to $15 incan maglite you have to add price of all other parts needed to mod, which results in
* Complete modified XM-L T6 Maglite - $129 (not including batteries or battery voltage monitor) Or add $25 for the Rebel build... (also not including battery holders)
Now C88 costs $45 with shipping, XM-L, good driver, pretty good press-fit heatsink which is able to divert heat from emitter well, and as was said in reviews, it is very nice looking, well build, feels good in hand, good mass for heatsinking, good beam... and personally I really like its design - simple and elegant. With extension tube attached it still has decent look, not very long (a lot of this is matter of taste of course)
Runtimes are better with maglite and two 5000mAh capacity 32600's, it's different category - but C88 with 6AA need not to be ashamed 
, it'll hold the same lumen output as good, just shorter - this is how I think about it
It is true that those battery holders have a higher resistance, but with freshly charged eneloops the default one shipped with Cyclone can give around 2amps at tailcap. As with parallel setup the overall resistance will be lower and max. current will be 1.4amp/cell - I think they will do okay as they are. But fixing them with a little solder or better springs would help to hold voltage¤t even longer. Or one can build its own 3s2p holder, no problem with that.
mio
I'd like to see a few more people weigh in on this - but if the OP is correct, I'm interested.
Jamio, JohnnyMac, Gary, dthrckt, et.al - I like the idea of carrying an extra battery holder and/or trying to mod a couple for efficiency. Can you guys tell from the eBay photos which would be the better one?