Heatsink machining drawing

[Joe34]

I have read that black is better at passing heat from a few sources.

But to add another value to the matter, Surely adding any colour dye to the anodized surface is only going to reduce the pore size(layer of dye has a thickness) therefore creating less surface area, overall making the heatsink less efficient...

 

[Johnnycannaseed1]

. A white colored object and a black colored object can both be black bodies.

Nice swerve Buddy... but that comment above was pure comedy. I will leave it to you to figure out the stoooopidy of it if you can...

Ah what the heck seeing as you are not the brightest I will give you a clue what is the closet definiton of an integrating sphere is it;
(a) blackbody
or
(b) whitebody

Hot tip: it cannot possibly be both of them like your quote above would seem to imply

Send your answers on a postcard buddy

Right that's 5 bongheads to me against your weak ass 4

 

[Johnnycannaseed1]

I have read that black is better at passing heat from a few sources.

But to add another value to the matter, Surely adding any colour dye to the anodized surface is only going to reduce the pore size(layer of dye has a thickness) therefore creating less surface area, overall making the heatsink less efficient...

Yeah consensus among the pro's and the science says black is pretty darn good.... But Raging stalk has convinced me, so I reckon pinks the colour to go for

 

[Danielson999]

Nice swerve Buddy... but that comment above was pure comedy. I will leave it to you to figure out the stoooopidy of it if you can...

Blackbodies don't have to be black, they just have to absorb all radiation that is incident upon them. As a great example, the sun is a blackbody. Is it black? no.

Now, I don't have the time or the crayons to explain this shit to you. Go do some damn research and educate yourself. You are the ultimate definition of stoooopidy (nice spelling btw).

Everything you've said in EVERY single comment in this thread has been absolute comedy. I do believe you know someone who told you black works better, I know people like that too. It's something people have always believed for simple reasons like touching a black car in the hot sun vs touching a white one.

Joe34, to expand on your thoughts, 'black' does not pass heat better, it absorbs radiative heat better. If our cobs were pointing directly at the heatsinks, a black one would absorb the heat better but fortunately for us our cobs are pointing in the opposite direction. Just the fact that our heatsinks are anodized is 100 times more important than what color they are. When you add in the fact that we are usually growing in a tent with ambient air flow cooling them...it makes the color completely irrelevant and moot.

 

[Photon Flinger]

Pink.

 

[CobKits]

What's the point in anodizing our heatsinks when the're not in contact with water

i believe its because it prevents oxidation of the surface, which apparently reduces heat dissipation

 

[Johnnycannaseed1]

Blackbodies don't have to be black, they just have to absorb all radiation that is incident upon them. As a great example, the sun is a blackbody. Is it black? no.

Now, I don't have the time or the crayons to explain this shit to you. Go do some damn research and educate yourself. You are the ultimate definition of stoooopidy (nice spelling btw).

Everything you've said in EVERY single comment in this thread has been absolute comedy. I do believe you know someone who told you black works better, I know people like that too. It's something people have always believed for simple reasons like touching a black car in the hot sun vs touching a white one.

Get the F outta here why are mixing up black body and black body radiation as being one and the same you are so full of shhhh

White body = reflects all rays of light uniformly and its theorectical temperature is 0 as in absorption and 0 emissivity... So how the heck do you equate a white body to a black body which is a 1 absorption and 1 emissivity last time I checked that makes them polar opposites
.

Black body = absorbs and emits electromagnetic radiation
Black body radiation = electromagnetic radiation emitted from a black body

So tell me einstein in this great example of yours how the sun is a black body, it's close to one but by the definition of the word it isn't one big distinction buddy


Sun = Red line

Think you need to take a dose of your own medicine and "go and do some darn research"

On that note I believe it is 6 Bongheads to me and you are no fun hahaha!!!

 

[Danielson999]

Anodizing is an electrochemical process that thickens and toughens the naturally occurring protective oxide layer on the surface of metal parts. Surface anodizing changes the microscopic texture of a metal, making the surface durable, corrosion and weather resistant. To further protect the surface of dyed anodized heat sinks from corrosion, they are usually sealed by immersion in boiling hot de-ionized water or steam.

Johnnywhateveryournameis, like I said, you don't even understand what a blackbody is. Go educate yourself, talking in here is absolutely pointless.

 

[Johnnycannaseed1]

Johnnywhateveryournameis, like I said, you don't even understand what a blackbody is. Go educate yourself, talking in here is absolutely pointless.

No more like you are full of shit and you have just been caught out, nice try though

 

[DankaDank]

i believe its because it prevents oxidation of the surface, which apparently reduces heat dissipation

As @daniel said anodizing increases the thickness of the naturally formed oxide layer (which actually decreases thermal conductivity) . I don't see the point in it for our purposes,its not like we are submerging our heat sinks in salt water every day.

 

[Danielson999]

I don't have crayons but I'll use an image to help your brain understand a bit better. A good example of a black body is a cavity with a small hole in it. Any light incident upon the hole goes into the cavity and is essentially never reflected out since it would have to undergo a very large number of reflections off walls of the cavity. Once again, try and wrap your head around the concept that a blackbody is one that absorbs all radiation incident upon it. Being black has no bearing on whether something is a blackbody or not. The sun is a blackbody, not a perfect one but nothing is. A black hole is also a blackbody but also not perfect. And guess what, your black anodized heatsink isn't a perfect blackbody either lol!!! For something to be a perfect blackbody it must absorb ALL energy directed at it. Unfortunately nothing does. Anyway, try wrapping your head around this because it's getting painful dealing with your shit. You don't even have a basic understanding of what a blackbody is so what's the point in us even talking?


Oh and by the way, thanks for calling me out, your really got me there. I'm done pointing out how clueless you are. You can lead a horse to water but can't make them drink. I'm done stretching this thread out responding to an idiot.

 

[klx]

Now you guys are taking it to the extreme if you are now trying to figure out the best color for your bulky over engineered heat sinks.

Ok, I vote pink just to be different.

You have been beating this drum pretty hard, but when asked about pics you dont have a camera. Would love to see some pics of ambient temps and IR temp gun aimed at your sheet metal heatsinks. Not that I dont trust you, I just dont trust anyone

 

[Joe34]

Joe34, to expand on your thoughts, 'black' does not pass heat better, it absorbs radiative heat better. If our cobs were pointing directly at the heatsinks, a black one would absorb the heat better but fortunately for us our cobs are pointing in the opposite direction. Just the fact that our heatsinks are anodized is 100 times more important than what color they are. When you add in the fact that we are usually growing in a tent with ambient air flow cooling them...it makes the color completely irrelevant and moot.

But we want to transfer as much heat to the heatsink as possible, so that we can use its larger surface area to dissipate it.
So if a black one absorbs heat better, more heat is being transferred to the heatsink - ideal scenario.

If you reflect it off the heatsink(like some of you guys are proposing), then your heatsink is completly pointless.

Also, to those asking why anodizing works.

To my understanding anodizing produces a much more porous surface(loads of tiny little holes)

Those holes increase the overall surface area, therefore an anodized heatsink = better than a non-anodized heatsink.

If you want to look at it another way, cut all those spikes off your heatsink, and leave just 1 in the middle, then measure your temps of the heatsink... it will be useless.

 

[Johnnycannaseed1]

I don't have crayons but I'll use an image to help your brain understand a bit better. A good example of a black body is a cavity with a small hole in it. Any light incident upon the hole goes into the cavity and is essentially never reflected out since it would have to undergo a very large number of reflections off walls of the cavity.

HAHAAHA what a Plagiarizing twat you are, stealing/cutting and pasting the words above then trying to pass them off as your own, talk about a loser...http://quantummechanics.ucsd.edu/ph130a/130_notes/node48.html

Once again, try and wrap your head around the concept that a blackbody is one that absorbs all radiation incident upon it. Being black has no bearing on whether something is a blackbody or not. The sun is a blackbody, not a perfect one but nothing is. A black hole is also a blackbody but also not perfect.

Give up the ghost clearly you do not really know what you are talking about and you have been well and tuly caught out you silly cut and paste king

And guess what, your black anodized heatsink isn't a perfect blackbody either lol!!!

Feel free to point me to where I said that... seems you have as much trouble reading as you do Plagiarizing other peoples words and not getting caught

For something to be a perfect blackbody it must absorb ALL energy directed at it. Unfortunately nothing does. Anyway, try wrapping your head around this because it's getting painful dealing with your shit. You don't even have a basic understanding of what a blackbody is so what's the point in us even talking?

Let me put it this way if I want a science lesson I certainly wouldn't be coming to you, because clearly you are a stoooooooooooooooooooopid plagiarizer who does not understand enough about what a blackbody is to be able to put it into your own words... Hence you steal words from people who do

Oh and by the way, thanks for calling me out, your really got me there. I'm done pointing out how clueless you are. You can lead a horse to water but can't make them drink. I'm done stretching this thread out responding to an idiot.
View attachment 3908210

It has been a pleasure exposing you for the clueless twonk you are, now go take a good dose of your own medicine and go and delete your crappy clueless posts!!!

I believe that is 7 bongheads to me and 0 to you loser

Ps a black body doesn't have to be black but why do you suppose they are called "black" bodies that is called a clue jackass!

 

[George2324]

Right ok...

looks like black anodised is cheaper and not sure what alternatives I could ask for anyway so will just go with that since my grow room has all light emitting away from the heat sink and no light should be reflecting back towards the heatsink due to canopy being directly below them with no reflective floor.

 

[Danielson999]

But we want to transfer as much heat to the heatsink as possible, so that we can use its larger surface area to dissipate it.
So if a black one absorbs heat better, more heat is being transferred to the heatsink - ideal scenario.

You're right, black absorbs it better, if it's light hitting it directly. In our use, with the cob mounted so the light points straight down and away from the heatsink this makes the heatsink being black pretty much irrelevant. If you put a brown heatsink and a black one in a dark room and heated them they'd absorb it equally. Since our heatsinks barely receive any direct light at all it becomes a non-issue what color it is. The only important aspect is that it's anodized, and this is pretty much irrelevant in our case also since how many decades of use would it take before our heatsinks start corroding even when they aren't anodized? Look at all the people who have used extruded aluminum from HeatsinkUSA, none of it is anodized and they've been using them for years with no concern. If anything, you'd want to make the downward surface as reflective as possible to redirect whatever tiny amount of light is hitting them back downward toward the plants. If I remember correctly, Growmau5 polished his heatsinkusa sinks which makes sense.
For our use in growing plants using LED's/cobs, the color and the fact that it's anodized is completely useless.

 

[Danielson999]

It would also make sense that since we want our heatsinks convecting as much heat from the cob as possible, we would want as little radiative heat being absorbed by heatsink. The cooler our heatsinks are, the cooler our cob will be. Why add extra heat to the heatsink by making it black when the heatsink is releasing heat through convection? Convection is not affected by color, which is why our computers have typically had bare aluminum heatsinks (until they started making them flashy colors for marketing purposes).

If we want our cobs as cool as possible to increase efficiency, it makes sense to add airflow to heatsinks and also make them resistant to radiative heat. Painting them white would make sense in that case. Food for thought anyway.

 

[Johnnycannaseed1]

You're right, black absorbs it better, if it's light hitting it directly. In our use, with the cob mounted so the light points straight down and away from the heatsink this makes the heatsink being black pretty much irrelevant. If you put a brown heatsink and a black one in a dark room and heated them they'd absorb it equally. Since our heatsinks barely receive any direct light at all it becomes a non-issue what color it is. The only important aspect is that it's anodized, and this is pretty much irrelevant in our case also since how many decades of use would it take before our heatsinks start corroding even when they aren't anodized? Look at all the people who have used extruded aluminum from HeatsinkUSA, none of it is anodized and they've been using them for years with no concern. If anything, you'd want to make the downward surface as reflective as possible to redirect whatever tiny amount of light is hitting them back downward toward the plants. If I remember correctly, Growmau5 polished his heatsinkusa sinks which makes sense.
For our use in growing plants using LED's/cobs, the color and the fact that it's anodized is completely useless.

Nice Idea Brainiac only one problem, you clearly have not thought your "brilliant" answer through properly have you lol?

Brainiac which side up is the Led package bolted to the heatsink, light emitting side or back?

Tell me does the back of the led package emit light or Heat?

Riiiight and which colour has the highest absorbption/emissivity value white or black?... Do you see where I am going with this?... No of course you don't well let me carry on for you.

What would happen to the emissivity value if you polished the Aluminium?

Yes of course it would plummet Brainiac... and how would that affect heat transfer from the back of the LED package?... Yes that's right Brainiac it's ability to absorb/emit heat would plummet due to the reduction of it's emissivity value.

Final question why do most of the major LED heatsink companies dye their heatsinks black?

Noobs looking for sound advice "IGNORE" Mr Brainiac Danielson because he's clearly lost without Mr Miyagi, to the point that he cannot fathom what the heck he is talking about.

If you look through the posts you will see as his posts go along he slowly concedes each point as he gets called out on it but never actually admits he was wrong in the first place.

IGNORE IGNORE IGNORE, because this idiot is CONFUSED CONFUSED CONFUSED and he will only end up confusing you further with his BAD ADVICE!

Black anodized is one of the best options out there period, so do not let Braniac make you think otherwise!!!

 

[DankaDank]

So I have been doing some reading and apparently our heat sinks, if any color, should be mat-black.

 

[mahiluana]

less surface

This is a pic of one of my first kits i sold.

It is a 3KG 1000 x 100 x 100mm sqare tube with the drivers mounted inside
and a 120mm fan at each end.
I scrubed the whole surface inside and outside the tube with greasy paper,
to have better heat transfer by a biger surface.
For anti corrosion i used to put a very thin cape of wool grease even to drivers and screws.