I have experimented with 5mm led's and their only really good for baby clones or vegging.
Then I ran into this website, www.ledgrow.eu, where a guy is covering six square feet with sixty watts of LED's
So I built my own, and will be posting the trial on here.
The light I made is sixty watts, however the leds have a 110 degree beam. I could focus the light with a columinator but im trying it like this first

Good luck with the grow trial afro.
Results i`ve seen previously haven`t been anywhere near as good as hps tho.

ive grown a seedling under a 5 watt led for about 2 weeks and it seemed to do very well, sixty watts should be enough to grow a whole plant according to sellers but the general consensus seems to be that its no good for growing cannabis. i dont see why personally theres no reason why they shouldn't work as long as you have enough of them. have you only made one light like that?

haha, its mounted on a cymbal? thats a damn good idea.

I assume you'll put it in a cylindrical growbox and top the plant to make best use of the light ?

I've seen them mounted on an aluminium baking sheet, you guys are just creative! And as long there is not serious heating up (in this case you should be able to touch the metal surrounding the LEDs without any problem) there is no technical reason why they shouldn't use whatever they want

PS: Did you use thermal glue or thermal grease with something else to glue on?

I used hot glue from the glue gun, the led's don't seem to get warm enough to melt the glue.

Oh dear .....

I hope the glue is only around the edges !

So you did use heatsink compound I hope ?

The one watt LEDs I bought a while back are drillable - and hence screwable I think ...

Any chance of a wiring diagram ?

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It'll be interesting to see what can be done with power LEDs. and the expertise of uk420.
The guy on the other website appears to be somewhat lacking in several areas ....

I once used hot glue for a bike light with a 1W high-power led (Luxeon, years ago). That one un-glued itself from the lens I attached it to. You will have to watch this carefully, or do what compostverte suggests for long term stability.

I did have some problems with the hot glue. I ended up removing it on some led's and reglueing with super glue.

Did you not look at clamping them mechanically for optimum thermal contact ?

looking forward to see some results from that lamp
i'm prepairing to my next project for quite a long time (money, time, grower,... problems) and i plan to use luxeon rebels mounted to aluminium or coper piece of metal. what leds did you use? any datasheets about them? what powersupply are you using?
i also think it would be better to use thermal adhesive and some screwes to attach the leds to that piece of metal instead of hot glue.
i'll be watching this thread.

Whazzzup (takes me back to the 90's).

Luxeon rebels are what i first tried to use. Unfortunately I couldn't find any colored ones that are mounted. I ended up using luxeon III's for the blue, since they have royal blue color which is closer to the optimal 430nm wavelength. For the whites I used the new Cree mounted LED's. I took the hot glue off and super glued the edges of the pcb. Im not too worried about heat, the pcb that the leds are mounted on is supposed to be able to dissipate the heat effectively . Mounting it to more metal just keep them cooler.

"But why the white LED's" . The answer has 3 parts:
1. The plants have a hint of green, which makes the plants look nice and allows me to inspect them without moving them
2. Small amounts of light are needed in the indigo and yellow spectrum the trigger proper production of accessory pigments

Lets put a space here, this is a big idea.

3. Far red light is produced by the warm white led's. Far red light is important for the proper fruiting of plants because it triggers the conversion of phytocrome far red to phyrochrome red and vice versa (when lights are on/off). The balancing act of the two different types of the Phytochome hormone is what is currently thought to be responsible for fruiting .I have noticed that the main problem with LED's is a low yeild. This could possibly be related to low yeilds in CFL's, since they too do not produce large amounts of far red light either. Of coarse, it could be a lack of light intensity in both cases, since I haven't seen any really high wattage led systems.

Using white crees isnt the best idea if you just need far red light, but at the time i didn't know of any other options. Now ive found a led supplier that have 740 nm far red high power led's. I would like to make a separate 60 watt far red light and use it only during fruiting ... curious. The only problem is that i just built a light, and feel a need to pace myself, also the forward voltages and max current for the leds arent standard like the cree or luxon.

Why not check them out for yourself?
http://www.norluxcorp.com/hex.htm

I would not recommend using the blue led's produced by this manufacture, since luxeons royal blue is closer to target. The red produced by this company is the closest ive seen to the max absorbance of red light (665nm) with their 660nm red light which has a half width of 20nm (so its pretty much perfect for the activation of photosystems and production of sugars)

Power supply?, I found a nice one on this website
http://www.powerstream.com/24-volt-dir.htm

Just thought I'd bump this thread for an update .

So it is the end for my plant b/c of the
Fuckin Spider mites

By the end the plant was supporting about 500 mites, smelled nice.
She was much too young, only 3 months from seed. Yield will be announced in a few days.

You cant really see the spider mites, but theres hundreds there not including the carcases of the dead. The overall leaf is pale , and in some spots its turned brown. Theres webs on and in between each segment of leaf.
Theres now hundreds on my cacti, im gonna have fun watching them starve to death.

seed it