Asking for Input on My First Bike Light

[kermit]

Hi all, I'm looking to cobble together a DIY bike light of some sort, but this will be my first mod/build, so I need all the advice I can get.

I have an Arc LSH-S that is cosmetically very beat up from a couple years of heavy use in Africa. To boot, the LED was physically destroyed when I dropped the light and it landed on its bezel.

I'm thinking of using the Arc as a host for a bike light. I'd like to drive a single Cree/Seoul via a board of some sort from an external 7.2V 2.4Ahr Li-Ion battery pack. I'll drill a hole through a non-functional kroll switch and install a female plug of some sort. I'll have the matching male connector on the leads from the battery. For my first go around I don't need an on/off switch, I'll just plug in the battery pack when I want light. I'd like to drive the LED at a minimum of 750ma, perhaps at as much as 1000ma. What board should I look at that will fit inside an Arc LS? At a diameter of 1", the bFlex will not fit in an Arc. A FluPIC would fit, but can't handle that voltage. nFlex is also too big. What else is there? I don't need multiple levels at this point (I'll save that for my next project!).

Anyone have any suggestions or guidance for me? I don't have access to a lathe or a mill, so fabricating any kind of metal part isn't a possibility.

I plan on mounting the light with either a thick o-ring a la dinotte or with a TwoFish LockBlock. This light will be for commuting on my 'cross bike in the city and in the suburbs.

Thanks for your help!
kermit

 

[bbaker22]

I just put together a small bike light w/ a Cree P4 and this board from Kaidomain:

http://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2982

The driver is small, provides 750ma, and accepts 4-18v input.

I've driven it w/ everything from 6.0v to 14.8v. The driver seems to handle them all fine. I have no long term data on durability as I just put this together this week.

baker

 

[kermit]

Hmm... I started thinking about this last night a little bit more. Perhaps I should just build a sandwich with a FluPIC. This would allow me to run the light with a CR123 or R123. I would then create a "dummy cell" that has a power connector on the bottom and have it set up to follow the proper electrical paths. ie. +ve to a button on top and -ve to the body of the light. Of course I'd have to use a 3.6V battery pack, probably two 18650 Li-IONs in parallel instead of running them in series. Now to figure out a switch that will allow me to use the multiple levels of the FluPIC.

This will allow me to use the light on or off the bike.

Any thoughts?