Runtime estimate

I'm gathering components to build a LuxIII into a Dorcy Cool Blue 4AA light. Can anyone help me predict the runtime for various configurations? I'm hoping to get a little over 1A. I'm thinking of using 2 600ma Badboys in parallel. Choices are (1) use 4 NiMh and a high binned LuxIII (2) use 3 NiMh + 1 dummy and a lower binned Lux III (3) use 3 AA Alks. (4) Any combination of the above but direct drive. Any thoughts would be appreciated.

Can the 4AA battery holder that comes with the Dorcy Cool Blue be modified (easily) to run 2 sets of 2AA in parallel? (Mine haven't arrived yet so I can't tell)

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sflate said:
I'm gathering components to build a LuxIII into a Dorcy Cool Blue 4AA light. Can anyone help me predict the runtime for various configurations? I'm hoping to get a little over 1A. I'm thinking of using 2 600ma Badboys in parallel. Choices are (1) use 4 NiMh and a high binned LuxIII (2) use 3 NiMh + 1 dummy and a lower binned Lux III (3) use 3 AA Alks. (4) Any combination of the above but direct drive. Any thoughts would be appreciated.

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That cool blue dorcy is my 1st led flashlight.
My vote would be to just go with 4 nimh batteries seriesed,
and a simple dropping series resistor with the right resistance to get the desired amperage.
Heatsinking will be a problem with that plastic flashlight case.
A single 600ma circuit for that lux3 would be about right if you want to go the regulated route.
Or easier still just drop in an everled 1 watt luxeon pr bulb in that, or any dorcy 4cell light.

My mistake - I should have said 'Dorcy Cool Blue Aluminum'. Good info though. I have been considering using a plastic flashlight case but not sure of the heat issue. I've been wondering if the heatsink alone carries away enough heat from the LED. I'm running a Badboy 1A w/ LuxIII in my MiniMag but would like to get just a touch more light out of it. I'm thinking about 2 Badboy's in parallel, I think there is a 611ma combo making it 1.22A total. I only want to do it if I can get a decent runtime though.

http://www.anlighten.com/shop/test.php is the url for a very nice runtime calculator... i think it has a built in efficiency in the mid 80s but it's very nice... to find the mAH of the battery in question, i usually go here: http://www.internet2.edu/~shalunov/materialism/flashlights.html

you can 'cheat' the formula pretty easy as well.. example.. if you know you want to run (3) lux3s in series, know the Vf for one.. you can triple the Amps vs. tripple the Vf (easier math) and it's all good.