Double Cree front light

[gbb]

For those that are interested, here's my first proper attempt at a DIY high power LED light...Components used...

2x Cree XR-E Star 3 watt LEDs
2x Optics
1x 700 ma driver
1x Aluminium enclosure
1x Toggle Switch
1x 2.5mm jack socket and plug
1x lump of heatsink
1x 10 AA battery holder

I cut, ground and fashioned the heatsink to accomodate the Crees and wiring
Crees were fixed using Thermal Epoxy
The box was chosen based on the size of the optics.
The driver is not the one widely available for this kind of thing...its just one i had easy access to. In reality, i think the Crees will take a 1000ma driver...so i've cut the light output somewhat...but its more than good enough for now.
The optics, again were what i could get hold of. I had to cut some of the base away to get them to sit over the wiring, but they're secure.
Switch and plug / socket were from maplins....very fiddly to solder the plug...maybe go for a bigger size if i did it again.

A few pics...

Some of the basic components..

Heatsink with Crees bonded..

Wiring attatched to LEDs...

Driver...

Tight fit..

Assembled..

Cateye mount fitted underneath..

Battery pack is 10x AA Nicads for now...a little underpowered at 950ma, they're just what i had...all temporarily mounted under the stem.
A piece of perspex has been fashioned to protect the optics.

Burn time is a little over 2 hours...not bad for some old 950ma batteries. Got some 2700ma's on the way. That should extend the burn time to well over 4 hours.
Temps on the heatsink are very good....running at 30 degrees C
Light output is good , i'll post some pics soon..

Its a fiddly job...there's quite a bit to think about when sourcing all the bits. Its fiddly to assemble, and cost wise...its debatable whether its worth it. But a good project all the same.

 

[Amanda P]

You're right, those Crees will take 1000mA, and it makes a difference. I've used the similar Seoul P4s, I think the Crees may be brighter for the same power. This constant-current power supply will do the doing, and LED-TECH are a useful supplier for all sorts of this kit.

Your light is quite similar to those described by Fisha (whatever happened to him?). I've now built four of these, and I'm very, very impressed with them. So is Mrs Uncle Phil, and she uses one of them now.

 

[Will1985]

Good job! How did you get that Cateye mount?

 

[NickM]

They unscrew from the bottom of old Cateye Halogen lamps - well worth keeping...

 

[Will1985]

I've been looking at this a bit more and found someone on mtbr who modified his Doubleshot. Looks a good idea to get more light, but I wouldn't want to try it on mine just in case something went wrong!

 

[gbb]

They unscrew from the bottom of old Cateye Halogen lamps - well worth keeping...

Spot on Nick...i had a pair of halogen HL-220 (IIRC) i got from a car boot last year...50p each .

You're right Uncle Phil..the box idea is widely talked about on t'internet. (candlepower forums etc)

 

[02GF74]

those are very much in the Fisha mode. really must get mine completed; maybe tonight..... last bit that is holding me up is a screen and sealing them to be waterproof-ish!

what did you use as the perspex screen? I am thinking of a a CD case -

 

[Amanda P]

For my first one, I used a bit of thin perspex that once served as the window in the case for a set of drill bits.

For the others, I cut up a spare clear plastic shield for a welding helmet. (It didn't fit my helmet - too small. If anyone wants the smoked glass bit, let me know).

CD case might be a bit brittle, but on the other hand, you'll only use a tiny bit and the chances of it being bonked or bent are very small.

 

[gbb]

those are very much in the Fisha mode. really must get mine completed; maybe tonight..... last bit that is holding me up is a screen and sealing them to be waterproof-ish!

what did you use as the perspex screen? I am thinking of a a CD case -

Im probably luckier than most, i work in an engineering workshop...theres tons of all sorts about...you just gotta find it

 

[Amanda P]

gbb, I'm interested in the case you used. Where did you get it from? Part number?

Up to now, my "Fisha" lights have all used external battery packs. If I use a slim driver (like the one I linked to above), there's almost room in the cases I use for four AA cells inside, but not quite. Your case looks bigger, and I'd like to try making a self-contained one; that might be possible with a slightly bigger case.

 

[02GF74]

that driver is huge!!!

take a look at these:
http://i7.ebayimg.com/04/i/001/29/48/4072_2.JPG[img][/url]

come in 1 W, 3 W and 5 W flavours.