Hi 1-2-3-4. What bridgelux LED model are you planning to use ? Is it the high CRI that you like to have ? It certainly looks good in the specs
Maybe we can look at another LED model with lower total Vf.
I was looking for the device in question here http://bridgelux.com/ .. but couldn't guess myself to what device you are looking at.

This LED here

http://www.digikey.com/product-sear...=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25

.." being 3/4" thick and 5" by 6""






Way too big for that size LED, try something thinner like 1/16", 1/8", or even 1/4" thickness.

Ok good to have other opinions.

 

This LED here

http://www.digikey.com/product-sear...=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25




I've been watching those LEDs for quite a while. Since I'm still in the experimenting stage, I don't want to spend that much for one LED.
The most I've paid per LED was about $11.00 for a single 50 Watter.
Which is very cheap, compared with current pricing.


However, I will see myself buying a few of those you linked to.

 

No this is for yard lighting I was just saying how reef tank users have a decent light setup but cooling is not that much of an issue because the heatsink is above the tank.

So anyways with the aluminum flat bar being 3/4" thick and 5" by 6" I assume it can take a lot of heat but sooner or later the heat as to come away and I don't think passive cooling is going to be that much.. What I need is a real world test to see how 6 LED's at 350mA is going to be on a aluminum bar of that size.

If you are still looking for appropriate heatsinks, try this site:


http://www.rapidled.com/as-is/


You are not going to find them much cheaper, unless you go Ebaying.

These may have a few dings, but they will be hidden in your hood.

 

If you are still looking for appropriate heatsinks, try this site:


http://www.rapidled.com/as-is/


You are not going to find them much cheaper, unless you go Ebaying.

These may have a few dings, but they will be hidden in your hood.

Not a bad.. site good prices, only thing is the cutout is a round like 4-5 inch hole.

 

This section is 6" wide. Should be wide enough to put a 4-5" hole in, as long as you are careful.:


http://www.rapidled.com/as-is-6-x-10-black-anodized-aluminum-heat-sink/