I'd like to make a ridiculous flashlight

I've got a fairly good knowledge of basic circuits, parallel and series wiring etc. I happen to have a large pentium 4 heat sink available in which i'd like to mount a decent number of cree LED's. I really only have some exposure to some cheap hong-kong websites such as dealextreme.com and kaidomain. That was the basis in which I was working off of originally. I'd like some good information on the best sources for this sort of thing. I sincerely apologize if this is commonly discussed on the website, since this is my first post.

Essentially, I'd like to make a highly directional low beam divergence light with a ridiculous amount of lumens. The power supply I can figure out on my own. However, I am in need of decent lumen/watt ratio (and CHEAP in high quantity) LEDs that I can mount to my heat sink. I've got a filtered variable voltage DC power supply up to 10A for testing to assist in my tinkering. In addition, I'd really like some good ideas on what type of lenses I can fabricate to this thing to get the long beam i'm looking for.

I can figure out the power supply on my own. It's a simple matter of voltage in amp/hours and voltage output. I really appreciate any help I can get, and any advice on future "appropriate" forum posting locations if this is not the best section for it!

Thanks a bunch.

Are you going to put a fan on the heat sink? That would probably allow for more LED's at higher currents.

If you are going for maximum output, but aren't planning to put a fan on you heatsink, I would go for some efficiency as well as output. I believe you can order the new XP-G LED (~340 lumens @1amp, as compared to the XR-E with ~250 lumens at 1 amp) from Cutter Electronics. With just a few of these, you can have as much output as one or two MCE's/P7's, but with much less heat.

John_Galt said:

Are you going to put a fan on the heat sink? That would probably allow for more LED's at higher currents.

If you are going for maximum output, but aren't planning to put a fan on you heatsink, I would go for some efficiency as well as output. I believe you can order the new XP-G LED (~340 lumens @1amp, as compared to the XR-E with ~250 lumens at 1 amp) from Cutter Electronics. With just a few of these, you can have as much output as one or two MCE's/P7's, but with much less heat.

Click to expand...

Yeah, I'd have no issues with using a fan. That's what the heatsink was designed for anyway. I'll just find a nice quiet one if the array ends up generating significant heat.

I have very little exposure to the general temperature limits of cree LED's, and I'm not even sure what an adequate operating range would be.

As a matter of practicality, I'd be willing to fork over a little extra money for higher lumen/watt ratios just to cut back on my cost of batteries. I'd like to get at least 1 hour of run time per charge while running all LED's. I noticed that a lot of these cree LED's already have mini lenses attached directly to them, and I'm not sure how this would affect focusing the array. Is there a particular LED a with mini spotlight lens attached so I would not need to focus externally? It would be nice to have a bunch of pre-focused LED's so I didn't have to worry about it. The beam I want should just be solid without any major spread.

Would something along the order of 5000 lumens be impressive?

take a look at this

https://www.candlepowerforums.com/threads/178130

some inspiration right there for you..

The only place i know of is deal extreme, with volume rate

http://www.volumerate.com/products.vr/just.released

if you want a directional low-divergence beam, you will have to go aspheric, such as Data did in the databank. Crees have plastic/silicon/(something i have no idea what) domes that effectively just protect the phospher as far as i know, so it offers no focusing to speak of.

Crenshaw