Wow, over a dozen posts in a row slamming one country or another. Arm Chair quarterbacks?
Where's the new layout?
The designer is sick from eating 3 eyed fish. Give him some time.
Wow, over a dozen posts in a row slamming one country or another. Arm Chair quarterbacks?
Where's the new layout?
That is incentive to produce quality engineering/product.
We said asia .... it really is problem. I have endured great pain (dermatitis)
from these products. I really won't even walk into a retailer that has
majority outsourced products - I get sick (it stinks , too) !
Mouser actually states country of origin , this means more to me than
price. I actually will ask origin from a Ebay store , as if the source is
***** , I KNOW it will fail 100%.
My german made sprint is busy with the symetri.
PS - If your own health or your family's health is directly threatened
by a certain country's products , that is like them coming to your house
with weapons. I consider this toxic , carcinogen laden breach a direct
attack.
OS
That GMO designation is a real problem in my eyes and this has been one of the reasons we are hearing so much BS about all of it. So many plants have been manipulated by humans for thousands of years now and we want to label everything that is done to be suspect? I agree I don't want a plant that contains glycophase poisons added to the gene pool, that is just crazy, but I dare you to find a citrus tree that is not a hybrid of one type of root stock and the rest of the tree being from another strain, it has been that way for at least 50 years. So we have to make some distinctions between gene splicing and hybridization, this is where the politics and media love to confuse the issues. As far as fish farms go even that is a misnomer in my eyes. We have both on land fish farms and those in the ocean. The ones on land, where most catfish is coming from have all the toxic runoff added to the water those fish are living in, those in the ocean are so close together that any problems from one fish are instantly shared with the other caged fish. We just need to limit the amount of wild fish taken from the oceans and let them come back. I say stay away from the older fish, Halibut, Swordfish, Albacore tuna and those fish that spend so much time absorbing the largest quantities of heavy metals,. And damn that low fat meet they call beef these days, give me a nice marbled fat cow, that is what I want to eat, the one that tastes like meet, not some piece of leather. My nephew, who I raised as a son, thought that he would be nice and paid a fortune for some fresh Bison, that stuff was so bad we weren't sure we wanted to give it to the dogs!
Now back to electronics,
While we are on the subject of heat sinks we need to also consider the profile of the extrusion, Just adding mass is not the answer and we are looking to lower temp through dissipation into the air and not absorption into a sink that at some point can't dissipate any longer. We want the maximum amount of surface area we can obtain to dissipate all that heat. So we have to not only look at the basic mass of the heat sink butt also the fin height and spacing. I guess we really only need be concerned with the the values that show the heat input to the sink and the loss out of the sink, but just looking at a heat sink does give a pretty good idea how well it is going to work.
Now back to electronics,
While we are on the subject of heat sinks we need to also consider the profile of the extrusion, Just adding mass is not the answer and we are looking to lower temp through dissipation into the air and not absorption into a sink that at some point can't dissipate any longer. We want the maximum amount of surface area we can obtain to dissipate all that heat. So we have to not only look at the basic mass of the heat sink butt also the fin height and spacing. I guess we really only need be concerned with the the values that show the heat input to the sink and the loss out of the sink, but just looking at a heat sink does give a pretty good idea how well it is going to work.
There's a lot of improvements that can be made even on Heatsink USA's extrusions. Wakefield adds a bunch of small grooves to the fins to increase the surface area even more. I don't think they offer as many profiles as the used to any more. Back to that costing a little more issue again.
I'm still tryng to figure out how to control the chatter when I mill thin fins. They vibrate like mad on the finish cut. I'm going to try a tapered end mill on the next one I do.
An anodized extrusion has greater surface area. A little less native transfer
from semi to aluminum (ZnO helps out) , but more from AL to air.
I'm thinking about my hot VAS now , not fish .... I threw them out.
OS
OS,
I am assuming you are talking about hard anodized aluminum here. I wonder how different that is compared to non coated aluminum that has formed its natural oxide surface over time? I'm not sure how the anodizing is adding much surface area, most of what I have seen has been fairly smooth as far as the surface is concerned. I use to have access to some huge platting tanks when I was working in aerospace, the largest tanks in California actually. I wonder if I can get some of my old employees there to do some platting for me? I was going to have some old Holley carburetors re-plated to look new but never got around to it.
I am assuming you are talking about hard anodized aluminum here. I wonder how different that is compared to non coated aluminum that has formed its natural oxide surface over time? I'm not sure how the anodizing is adding much surface area, most of what I have seen has been fairly smooth as far as the surface is concerned. I use to have access to some huge platting tanks when I was working in aerospace, the largest tanks in California actually. I wonder if I can get some of my old employees there to do some platting for me? I was going to have some old Holley carburetors re-plated to look new but never got around to it.
There are a lot of methods , some improve ... some do not . The oxide is an
insulator to the copper slug of the semi. The grease fills the pores to reduce
this. On the fin side the pores increase thermal emissivity 90%.
"The Surface Treatment and Finishing of Aluminum and Its Alloys, 6th Edn"., pp. 1092-1094 (2001) -a 200$ book ,but it covers all the plating/anodizing.
PS - the al2o3 is JUST an insulator (natural oxide).
os
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Extruded heatsinks are not the best and expensive solution. Everybody likes them because they are neat looking.
Take a look how they designed the HS for a old pentium plugin module, thin Al fins folded back and forth (acordian style) I guess welded to a Al plate. I have seen this done by Sony on some of there amps. It is maximizing the exposed area which counts. Jeff is the metal fab guy, he may know a easy way to make these.
Thinking about it, for the weight of a extrusion, you could get the same thermal performance out of the thin fin design for what? less than half the weight I am guessing.
Take a look how they designed the HS for a old pentium plugin module, thin Al fins folded back and forth (acordian style) I guess welded to a Al plate. I have seen this done by Sony on some of there amps. It is maximizing the exposed area which counts. Jeff is the metal fab guy, he may know a easy way to make these.
Thinking about it, for the weight of a extrusion, you could get the same thermal performance out of the thin fin design for what? less than half the weight I am guessing.
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Extruded heatsinks are not the best and expensive solution. Everybody likes them because they are neat looking.
Take a look how they designed the HS for a old pentium plugin module, thin Al fins folded back and forth (acordian style) I guess welded to a Al plate. I have seen this done by Sony on some of there amps. It is maximizing the exposed area which counts. Jeff is the metal fab guy, he may know a easy way to make these.
Thinking about it, for the weight of a extrusion, you could get the same thermal performance out of the thin fin design for what? less than half the weight I am guessing.
All the Japanese HT's do that. Works VERY well (how much convective heat
rises from them -below).
OS
Attachments
Those will likely dissipate around the same heat as the style I built for my load resistors. Lots of surface area without a lot of aluminum is probably the best design. Less thermal resistance that way. It might be worth experimenting with this.
Attachments
Depending of the way we coll them (vented or natural convection) the best profiles are not at all the same.
Natural convection ask more space between vertical fins, to let the air moving naturally, thickness of the base helps to equalize the temp of multiple devices etc...
Like for CPUs of computers, the contact surface between the active devices and Heat sinks is very important. Polishing mirror the heat sink can save degrees.
Thermal resistance of the insulator pads (if any) and quality of the thermal paste is important too.
In fact, correct design of a good cooling arrangement in an amplifier is a full work in itself, takes time and lot of trials if we want the best.
Natural convection ask more space between vertical fins, to let the air moving naturally, thickness of the base helps to equalize the temp of multiple devices etc...
Like for CPUs of computers, the contact surface between the active devices and Heat sinks is very important. Polishing mirror the heat sink can save degrees.
Thermal resistance of the insulator pads (if any) and quality of the thermal paste is important too.
In fact, correct design of a good cooling arrangement in an amplifier is a full work in itself, takes time and lot of trials if we want the best.
Theoretically a mirror finish should be bad for heat transfer. It may give better surface contact but the reflective surface will also reflect heat.
I've seen lots of talk of computer geeks polishing their heat sinks and they tell you how much better it cools, but they never actually back it up with any data and never even have any sort of measuring equipment in every article I've read on the subject.
This is also something worth properly investigating. When things slow down a bit for me I think I'll make up a few twin heat sinks and finish them to different levels of polish and different exterior finishes and do some proper measurements.
I'm not sure how to go about properly comparing billet extrusion designs to stacked or welded fin designs. The advantage of stacked or welded fin design is the ability to have longer fins easily. Comparing extruded to assembled heatsinks that are dimensionally the same would likely prove that solid extrusions are superior but that's not really the intended goal of the design. The biggest issues I see with the stacked or welded fin design is the space they require and the fact that if we were to use them on the exterior of an amplifier as most of our high power cases are done, they will be damaged quite easily. The billet fins are more immune to being bumped or hit.
There is no need for measuring equipment, as CPU has them inside
The improvement depends of a lot of factors, including the kind of thermal paste you use.
Let say, on my last computer build, and a liquid cooler, it was a ~4° improvement at 100% burn between the original yet shining surface and the same surface highly polished with a very liquid few thermal past expelled at high temp as much as possible.
i5-3570K Ivy bridge @ 5Ghz - CPU - Overclocking, Cooling & Modding - FORUM HardWare.fr
Of course, if we are in need to use an isolation pad, all this has no meaning.
I don't agree. It increase the contact surface between the two pieces. If not polished, it is air, or thermal past of more thickness, that have a less good thermal resistance than the cooler's metal itself (aluminium or copper).
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