Looking for heatsinks
 

Does anyone know of a place in Calgary or even online within Canada that sells heatsinks large enough to make LED lights, I know there is a couple in the US like heatsink USA, but shipping is pretty expensive, trying to look for local to save and to support our own industries at home!!!!

Thanks.

You could investigate other alternatives to the standard fin and fan heat sink. A tube style heat sink can be more effective at cooling and cost less. Square aluminum tubing is available locally from many sources.

+1 - if you can weld the square tubing into a continuous loop or back and forth pattern you can use a "side-venting" fan (possibly called a scroll fan??) to push air through the entire structure and keep it cool. You can effectively cool the entire unit with one fan (unless you have a 6 foot tank :))

Yeap or you could use a fan on each tube to make it a little easier or join the tubes with some other means. Not too many people can weld aluminum and contracting it out won't be cheap.

Just wondering, I have look at a few of the DIY LED setups, and everyone has huge heatsinks.

I personally am not using LED, but if LED uses less energy and has less heat creation, why such a big heatsink? Just wondering, as my MH, just have fans with no heatsinks.

The heatsink is to dissipate massive heat from the LEDs, which will theoretically extend their lifespan. Each of these little suckers generates a LOT of heat @_@

Just like any electronic component, the hotter it runs, the shorter its lifespan. A good example are CPU's and their honkin' heatsink/watercooling setups. Sure it will still run at the higher temperatures, but are you willing to risk burning it out? I think that's the fear.

Having said that, I do believe these big Amp style heatsinks are overkill for these LED setups. I just finished my 8LED build with a 6"x7" heatsinkusa heatsink, it's about 5lbs. It gets warm to the touch pretty quickly, but I have a 80mm fan sitting on top of it, running at about 5V (it's a 12V fan), and that's enough to cool the heatsink down to slightly cool to the touch.

When I do my next build, I'm using aluminum channels (not u-channel). I think the main thing is to slap on a decent fan to blow away the heat from the heatsinks, so they can continue to suck the heat away from the LEDs. I read that some guys would rather have a big ass heatsink, so that they can avoid adding a fan (due to noise) and just let it air cool. I cant even hear my fan when it's on.

Wish I had better news, but when I was looking I drew a complete blank - I would've liked to get something locally, or even in Canada but found pretty much nothing. I'm instead going with a large aluminum channel with a smaller one nested inside (thermal grease between the two) and holes drilled in the bottom of the channels to allow air to rise up through instead of stagnating in the bottom of the channel. I will also be using some fans to push air up through and assist convection. I'll make it clear I don't know exactly how well this is going to work since the light is still in the build process - I will be watching temperatures closely during testing. I'm hoping this will work well since my LEDs are going to be fairly tightly spaced.

I'm also interested in the idea of using heat pipes to push the heat from individual LEDs to a number of processor coolers, each handling the heat form a number of emitters - mainly because I'm a bit of a nerd and think that heat pipes are cool. :mrgreen:

LEDs are very efficient at turning electricity into light with relatively little waste heat. That is not to say they don't produce waste heat though. The rub comes in the fact that the emitters are producing that heat in a very small space (i.e. the junction) so the energy density is high, and to make matters worse the junction needs to be kept relatively cool for reasons of efficiency and longevity. For this reason people tend to go for huge heatsinks that can soak up the heat at a prodigious rate in order to be sure those junctions are being kept cool. The bulk heat produced at the end of it will be a lot less than your MH lights which actually have to be very hot in the part of the bulb where the light is produced.

I personally suspect that these heatsinks are a little overkill, but they provide a handy broad flat surface on which to mount the emitters, and after spending hundreds on those emitters a large heatsink seems like a small price to pay for protecting the investment. Bear in mind also that most of these large, flat, finned heatsinks are by necessity mounted in the most inefficient way possible (i.e. flat, fins pointing up) with regard to convective cooling, hence the fans to offset this..


Besides, those big heatsinks just look so cool - especially if you can anodize it a funky colour! :mrgreen:

i went to home depot today and saw some 1"x48" aluminum square tubes that might work, making them like a t5 bar, add enough fans it will work i think, i will try one to see how the heat is, but i suspect it will work really nicely.

I recall reading somewhere that 1.25" x 1.25" x 0.125" 6063 aluminum works best for this application.

You could look around for a place that recycles electronic components, shouldn't be that difficult in a large city. They'll have plenty of heatsinks out of old computers etc. Trick will be convincing them to sell you the stuff rather than ship it off for 'recycling'. I recall when I lived in Ottawa, there was a place in the south end where you could get all kinds of surplus electronics dirt cheap.

Only downside I guess is that your lighting set up might end up looking like something out of a '60s horror movie.

I thnink it would be interesting to see a pc liquid cooling concept applied to cooling LED's. Most kits are inexpensive in the grande scheme of things and allow expantion.

Would empty aluminum soda cans work? Put the leds on an aluminum bar stock and then use some thermal glue to glue a bunch of soda cans end to end(caps removed) and have a pressurized fan blow air through the soda can tube?

check out "Steve's" LEDs. he used 1.25 square tube with 1/8th wall thickness and uses these fans on the end of the tube.
http://shop.stevesleds.com/Cooling-Fans_c11.htm they are the cooling fans from sony wega's you can get the fans cheep from him and then buy some tubing at your local metal shop.

Steve

Loads of shops weld aluminum.

If your interested in persuing this route, pm me and I'll forward my contact list on to you.

The idea of a heatsink is to provide a large thermal mass which has as large a surface area as possible. The larger the thermal mass, the more "sinking" of heat. Most heatsinks have 'fins' since this dramatically increases the surface area exposed to ambient air. The more surface area for a given ambient temperature, the more heat that is transfered to the surrounding air.

Have you tried pricing solid aluminum plate -say, 1/2" thick ? You could make fins 1/4" deep in that with a table saw quite easily.

would be cheaper ordering from the US I think :mrgreen:

a heat sink is not as much about mass as people think, here is a def "A heat sink is a term for a component or assembly that transfers heat generated within a solid material to a fluid medium, such as air or a liquid."

a heat sink actually works on surface area not mass, the more surface area the more heat transfer. if you rely on mass then you will adsorb a lot of heat into the material but you won't be able to give it up fast enough and eventually the actual heat sink will get to hot. the fins are to increase the surface area so it can dissipate the heat faster than it builds up. fans can compensate for lower surface area, and increase efficiency as the rate of heat transfer is also a function of the difference in temp between the two mediums.

a hollow square tube 1.25 x 1.25 will disperse more heat than a solid 1.25 x 1.25 bar, because it has twice the surface area, this can even be increased further by supply fresh air with a fan which is increasing the flow over the surface also keeping the air at the surface cooler and increasing the rate of transfer.

the main reason we want to go with the single sided finned aluminum is looks. it is much easier to make it look good, but if you have some kind of enclosure in mine or are retro fitting into a hood then the square tube will work better as it will have a continuous supply of fresh air, where a fin type would be subject to the hood temp unless you vented you're hood with big fans.

the best place in Canada to find single sided finned AL, depends on where you are.. there is a couple companies in van that will bring it in.. probably charge you an arm or a leg though. same as Edmonton ect.. if you are in between like me and don't have the time or money to travel to look for it then you are stuck with metal recyclers, I have both here going to call me when they get what I am looking for in. they had some but it was double sided and I don't have a milling machine to make it single sided yet.

Steve

take your shells and put them where the sun dont shine'

Anyone looking for the square tubing for heat sinks can get it at Metal Supermarkets, the location in Calgary has plenty of 1.25x1.25x0.125 6061 in stock. Cost me $80 for 16 feet.

is that what your using for yours?

I have seen 90 degree ends that that size of tubing can slide into.. just have to remember where, as that would mean you could do several runs with one good fan.

Steve

Yes I'm taking this approach, I considered running a single fan but in the end I decided just to run 4 separate tubes each driven by a single fan.

I thought about this way also. separate fans will use a bit more power but the heat removal will be more efficient as in a long aray driven by a single fan the air temp would be more by the end.

which fans are you using?

Steve

Yes !

But notice I said THERMAL mass. Think of it like thermal capacitance or heat capacity. In the end though, you are correct -it's about the transfer from one medium to the other. You can actually have a very small and light heat sink but at some point, as the thermal mass decreases, you'll need a fan. Whereas with a more thermally (and to an extent, physically) massive heat sink, you may get away without the fan.

ok you are using different terms than we used in thermodynamics :mrgreen:

for instance heat capacity is how much a material will hold, which is what we don't want in this aplication as we want it to transfer it as fast as it can, not hold it.

and thermal mass is realy a measument to the resistance of temp change.. more specificaly the ability to hold heat and release it slowly, which again we don't want.

what we want is a material that has a high thermal conductivity, which means it passes on heat very easily when there is a temp difference.

so we mean the same thing I guess, but your choice of words confused the issue :wink:

Steve

I ordered the Pressurizing Cooling Fans from Steve's LEDs. I also ordered most of the LEDs for my build and drivers from him.

cool, I have been thinking of using his for a test build, but let me know what you think of his stuff. to bad you didn't have a PAR meter or live closer.. I would like to see how the edison LEDs preform compared to the Cree. I think my only problem with Steve's LEDs is he has no nutral white.

Steve

Will do, one of these days I'll update my build thread on some of my progress.

I just went with his 10K and blue leds, 56 of each. I then ordered some red and yellow LEDs from another supplier so I should be able to get the color and effect I'm looking for. I went with Steve's LEDs mostly because he seemed to have the best balance for performance and price plus his LEDs have a 90 degree spread so I won't need any optics which I prefer. The crees are nice but for the price I think these will be more than adequate for what I need.
I'll also be using the profilux PWM LED control 4 to control everything so I guess we'll see how that works out.

Princess Auto
 

Princess Auto had U shaped Aluminum Heatsink that you can use.

Hope this helps

I know this is a bit of a sidetrack from what you guys are talking about and it it works better living close to the border but this is what I did. I ordered heatsinks from rapidled, it was free shipping within the US. Many small towns along the border have businesses that will accept packages for Canadians. I got the package shipped to that business, gave the heatsinks plenty of time to ship and then went and picked them up. You have to enter into the states and declare them at the border but it easily saved me a couple hundered on shipping expenses. Just a thought for ya if your within proximity to the states.

I just wanted to add that the cheapest I found for heatsinks is LEDgroupbuy.com.

In Calgary, I got my C-channel aluminum at metal supermarkets. They have any kind of shape/metal you would need and much cheaper than Home Depot. http://www.metalsupermarkets.com/

you can get heat sinks from rapid LED they are canadian progressive reef now sell there product. You dont have to go through progressive to get them it is just an option

I dont have any cree running at the time (have 100 ready to build) but now have one pendant with the S. LED's and I findthy are doing gust fine.


I have them (28) on 2 heat sinks with the 60 degree lenses on them above a part of my 30 inch deep rank.

it is gust that with a Group buy the Cree where cheap so I both about 100, but with the steve once I think you get a fair bit.

I have green zoa's on the gravle that are doing gust fine, and about at 18 to 20 inches deep a nice birds nest that has growe from a tiny 1/4 inch tip to a 7 inch nest in a year.

from the 18 to 20 inch depth upwards there are some more SPS as well as a clamp, and some LPS. so far it is running for a year and I cant se any diferant in growth ore color of the coral when compairing with the 250w phounix builbs (exept the spread, as everyone knows the LED's are more concentrated.

when I build my steve LED poendant, I got a hell of a service, and cant compliment him more for that, he realy want you to have it working well.

in the upcomming weeks I will put cree's next to the steve led's (same amount of led's per pendant, and would be nice to se the diferant, if it is extream, I might need to put the steve led's above my frag tank

Ya from e-mailling back and forth with him I can't knock his willingness to help you out and his recomendations are not over inflated from my experiance.

I look forward to seeing some comparasons from you.

Steve

One thing many people fail to take into consideration is once you add in everything, aka you need more LEDs for the same amount of light, you can't run Steve's leds at the same currents (aka 1000mA max for XP-G, 3000mA for XM-L), the forward voltages are higher = more power use... long term a Cree setup will very likely save you money.

For example a Cool white XP-G puts out around 270lm at 2.4 watts while a 3 watt Pure White 7,000K LED - 2 Chip EpiStar puts out 220lm at 2.4 watts.

So if you are running 50 R5 Crees ($4.95 on ledgroupbuy.com) at 700mA they put out about 260lm each using 2.27watts. You are putting out 13 000lm using 113.5 watts.

To get the same amount of lumens from the EpiStar quoted above you would need 59 (at $3.49each) leds running at 700mA using 141.8 watts. That a difference of 9 more leds and 28 watts of power. I typical reef setup of a large tank could easily use 30-60 more watts to run and 10-20 extra LEDs.

50 XPG is $247.50
59 EpiStar is $205.00

Once you factor in the price of the extra LEDs, possibly more drivers due to higher forward voltages (the forward voltage listed isn't precise, so I can be sure), possibly more heatsinking, wiring, adhesive/grease/screws/tapping and energy use of many years it isn't necessarily more expensive to use Cree.

Just food for thought. Steve's LEDs is highly recommended and I've only heard good things. I'm not trying to bash the company in any way. I'm just saying, consider everything.

yup this is true but.. you may not need extra LEDs at all, the coverage is going to be the same if you have the same degree of lense so coverage wise the amount of leds will remain the same. power wise.. you may not need all the power available to a cree. there are countless people who have there crees running at 700mA then they are only using about 60% of that.

so for a smaller tank under say 18" of depth, if steve's LEDs will give you the PAR you want on the bottom of the tank, why spend extra?

the only issue I am having now is for white I want nutral white not cool white, and I want to get ahold of a few TV LEDs to see the color mix befor I buy a lot. this presents a problem as Steve only has 7000K and 10000K whites and royal blue not the 5000K I want for white or the TV I want to test out instead of the RBs

Steve

This is true.

When most are dialing their LEDs back so much, up to 40% in some cases, I can't understand why the recommended number of LEDs isn't adjusted. If you need half the LEDs, fire some 60 or 40 degree optics on half the number of LEDs and raise the fixture a bit. Get your coverage, save money, keep the intensity and the best advantage, the change in par at different levels of the tank won't be as drastically different due to the inverse square relationship of the intensity to distance for the LED.