Where to Buy Single Heatsinks for Cree Q5 & R2?

[davegLED]

Hi everyone,

Just about to order my first high power LED, Cree XR-E R2:

http://www.dealextreme.com/details.dx/sku.15943

Havn't chosen what driver yet, I will be running it from 12V.

I can't seem to find a source for heatsinks. I want to drive it at about 750mA and need something to mount it to. Any ideas?

This feels like a noob question but I searched with no luck?

Cheers,
Dave

 

[tx101]

What host are you using ???

 

[davegLED]

What host are you using ???

Appologies but I don't know what you mean?

I found a picture, something like the metal heatsink in the photo:

 

[tx101]

I meant what torch are you going to use the XRE on

 

[davegLED]

Can you tell I'm new at this!


There is no host at the moment, I just want to start experimenting to get an idea of how bright they are and how much heat is produced at driving currents.


I know Deal Extreme have had problems with phoney emitters but this doesn't matter for me to practice with.


If all goes well I will use an emitter as reverse lights in my car – the stock bulbs are useless!


Thanks you very much for taking the time to help me get started at this.

 

[tx101]

The only thing I could find is these

http://www.leds.de/shop_content.php?coID=23

Not exactly what your looking for :shrug:

Other than that, find some aluminium rod the right diameter and cut it to size

 

[davegLED]

Thanks TX101, I found these on the site:

http://www.leds.de/p284/High_power_...ories/Heatsink_51_x_51_for_HighPower-LED.html

That's what I'm after, just something to attach it to for testing. I have no idea how much heat these LEDs produce at 700-1000ma so it will be interesting to find out.

If aluminium bar works just as well I will get some of that to try. I can imagine it's hard to get a smooth cut though.

Edit: Found some more now

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=280309801217

 

[tx101]

LOL .....

Go to PC World or Maplin, look in the computer component section and you will find similiar heatsinks. I think they are called "chip-set heatsinks"

Yup, just had a look, Maplin have a whole section on heatsinks

 

[vali]

Or even individual memory chip heatsinks (but, probably, they will be too small).

 

[davegLED]

Cheers for the ideas.

I found these which look cool:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=180322172501

Maplin have free delivery too which is a bonus.

All I have to do now is work out how many lumens the stock 21W 12V bulb provides. Then I can work out how many Q5 or R2 emitters I will need. Any tips on how to calculate or find this out?

 

[davegLED]

Just read a link on google that stated incandescants produce approx 15 lumens per watt, so for a 21W bulb that is 315 lumens :sigh:

Looks like I'll need 2 overdriven to 750ma to beat the stock bulb.

It's going to be a squeeze. I wonder how much the star PCBs can be trimmed without having a negative effect on heat dissapation?

 

[spencer]

It doesn't even have to be a finned heatsink. All you need is a big chuck of aluminum. You should be able to find that locally. A computer heatsink will work as well. You can also find that locally. I went into a computer shop and he had a whole box of old heatsinks. My choice.:devil:

 

[rufusbduck]

When you are playing with your new toy, you can set the star on a 1" copper pipe cap while you solder wires or just want to "make it go". Copper pipe of various diameters also works well for potting drivers if you can then artic silver that to the case. With higher power mods, I like the idea of creating separate thermal paths to ambient for the led and driver(things are hottest at the source).

 

[davegLED]

THanks for your input guys. I have got hold of an older desktop heatsink and fan to do my testing. I have some Artic Silver thermal compound to put between star and sink.

I have bought one of these drivers and sockets:

http://www.dealextreme.com/details.dx/sku.13557
http://www.dealextreme.com/details.dx/sku.13558

You guessed it, I got these as they are cheap. I am having some aluminium heatsinks made for me for my first project if testing goes well:

The LEDs will sit on the tapered head of the sink. I presume the driver won't get too hot as I checked the datasheet and it seems to be a switching regulator not a linear one.

I'll update the thread when parts start arriving.

Cheers again,
Dave