Stupid Swiftech.

wussboy · Post by **wussboy** » Fri Jan 09, 2004 11:28 pm

Why would they sell a copper waterblock and an aluminum radiator? I just didn't check closely enough. Grrrr.. Am I screwed? Should I replace one?

chylld · Post by **chylld** » Sat Jan 10, 2004 12:25 am

Make sure you use water wetter or that zerex racing fluid stuff. If you don't then yes you are quite... unfortunate.

If I were you I'd get a new copper radiator

herosformula · Post by **herosformula** » Sat Jan 10, 2004 10:01 am

Swiftech water blocks use aluminum tops and copper bottoms, so you were doomed to some type of additive anyway. Too bad all of the really good ones have been banned.

silvervarg · Post by **silvervarg** » Sun Jan 11, 2004 12:24 pm

Shouldn't you always use an additive anyway?
At least for the reason to stop bilogical growth in the water. Possibly for other reasons as well.
Or is this unnessecary if you use destilled water?

chylld · Post by **chylld** » Sun Jan 11, 2004 12:37 pm

It is definitely still necessary. I've read of many people on Asetek's (manufacturer of the waterchill products) forums who have had their parts start to turn colour, i.e. corrode. And they used the recommended amount of the supplied anti-algae fluid. Furthermore, the asetek kits are copper - no aluminium.

herosformula · Post by **herosformula** » Sun Jan 11, 2004 12:47 pm

I make a distinction between "you need an additive anyway because everything corrodes eventually and bugs are bad" and "you just created a battery, in short order your parts will disentegrate into mush"

chylld · Post by **chylld** » Sun Jan 11, 2004 12:54 pm

I like the second analogy

(it applies to the topic's scenario)

what do you mean though in the first one: "bugs are bad"? are insects going to start breeding in san-additive watercooling solutions?

Gooserider · Post by **Gooserider** » Sun Jan 11, 2004 7:13 pm

In this context, "bugs" equals random forms of biological life that can and will grow very nicely in a WC system (almost without regard to coolant mix) and cause significant clogging problems. Distilled water doesn't stay pure, it will dissolve some stuff out of your system as soon as you pour it in, and that is adequate for life forms to grow. There are also some critters that LIKE antifreeze. It is almost essential that you use some form of biocide in your cooling system. Antifreeze is generally not biocidal, since in a car cooling system they assume that the high engine temps will kill everything.

Gooserider

herosformula · Post by **herosformula** » Sun Jan 11, 2004 10:10 pm

Biologists have a name for the warm wet environment inside of a watercooled computer: incubator, a perfect media for growing all sorts of nasty critters.

I do not use antifreeze. The primary function of antifreeze inside of an automobile is to change the freezing and boiling point of water (it also provides corrosion resistance). Since the amount of heat generated by the cpu is not enough (keeping in mind the flow rate) to get the water to boil, and I doubt that the water is in danger of freezing - it is unneeded. Couple that with the fact that antifreeze is a far worse conductor of heat than water, you would do better with a small amount of corrosion preventative, such as a few ounces of water wetter.

For the bugs, I used drops of liquid fungicide.

BTW: propylene glycol (one type of antifreeze) is also used as the base of cough syrups

wussboy · Post by **wussboy** » Mon Jan 12, 2004 6:12 am

Gooserider:

What's your opinion of my copper and aluminum problem? If I dump in that bottle of anti-corrosion crap that came with my waterblock, will I be okay?

Also, how important is and anti-bacterial in a closed system (ie. no reservoir)?

Thanks.

silvervarg · Post by **silvervarg** » Mon Jan 12, 2004 8:35 am

Gooserider:
Antifreeze is generally not biocidal, since in a car cooling system they assume that the high engine temps will kill everything.

So, all you have to do is to turn off your fans once in a while (keep pump on) and wait until your CPU temps climb near critical. Then you would have killed the biological things and you can turn on your fans again

I guess the classical approach of just changing the fluid once in a while would be simpler and less dangerous to the hardware.
Sometime 20 years or so back in time I had a waterfilled bed (cool at the time), and there was some stuff that you poured in the water to kill all germs. You added a small amount of this stuff every couple of months.
One small bottle would last like 2 years for an entire bed filled with water, and cost was rather low. It should easilly be enough for a lifetime with water cooling computer systems.

It might not have anything to stop electrical or anti-corrosive effects.

Wouldn't just grounding the waterblocks and the radiator elliminate any electrical effects?
I guess you still need something to stop corrosion.

herosformula · Post by **herosformula** » Mon Jan 12, 2004 8:39 am

PVC tubing is not a barrier to biological life - they will get in, and they are already in the water you will use. You can only manage them, you cannot defeat them. (Why does this sound like a B rate scifi flick?)

efcoins · Post by **efcoins** » Mon Jan 12, 2004 9:38 am

wussboy wrote:Gooserider:

What's your opinion of my copper and aluminum problem?

If the alu is annodised or electrically insulated from the copper then it will not corrode.

Otherwise put a piece of zinc into the rad or res, then it will corrode instead of the aluminium.

wussboy · Post by **wussboy** » Tue Jan 13, 2004 9:33 pm

Hmmm...I don't have a reservoir, and I can't really see a way to stick zinc into my radiator. How do I electrically insulate it? It will not be touching the case, and only connected by the tubes (ie: the pump and radiator will be in the next room), but water conducts electricity, no?

efcoins · Post by **efcoins** » Wed Jan 14, 2004 6:39 am

water conducts a little bit but not much.
If you use water additives then they may make a difference, but I doubt it.

In some systems everything is earthed, which causes a problem, but you will be OK from your description.

if you have an ohms meter then measure the resistance, >10000 ohms is OK <100 is not

Gooserider · Post by **Gooserider** » Wed Jan 14, 2004 6:05 pm

wussboy:
What's your opinion of my copper and aluminum problem? If I dump in that bottle of anti-corrosion crap that came with my waterblock, will I be okay?

Lots of people use Swiftech gear, and seem to like it. Their blocks are annodized which theoretically reduces the corrosion potential (slightly). Their CPU block is supposedly one of the better blocks for cooling performance. However I am conservative, and will NOT mix metals regardless.

If you do use Swiftech gear, the bottle of anti-corrosive is REQUIRED - if you don't use it or an equivalent anti-corrosive, your warranty is VOID, and the block will fail in short order. (There was a big thread about this over on ProCooling, it involved BillA (one of the top WC testing gurus, also now a sr. engineer at Swiftech) and a kid who had a catastrophic failure in a block that was less than 6 months old.) Note that if using a chemical anti-corrosive, you MUST replace it periodically as the stuff wears out.

I will use anti-corrosives even in my all Cu/Brass system, but that is mostly insurance rather than absolutely vital. I don't put my trust in mechanical safeties or chemical protections as it is better to design the failures out in the first place.

Also, how important is and anti-bacterial in a closed system (ie. no reservoir)?

It really doesn't matter what kind of system you're running - biocides are always adviseable. As herosformula said, the bugs are always going to be there, you need to do something to keep them under control.
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silvervarg:
So, all you have to do is to turn off your fans once in a while (keep pump on) and wait until your CPU temps climb near critical. Then you would have killed the biological things and you can turn on your fans again [\quote]
I assume you are being sarcastic however the approach would probably not work in any case - The specified faillure point for a CPU isn't high enough to get a clean kill, and you would probably reach a thermal equilibrium in the WC system before you got to the failure point if the water is circulating and the system is designed right. At any rate it would probably be harder on the hardware than it would be on the bugs.
I guess the classical approach of just changing the fluid once in a while would be simpler and less dangerous to the hardware.
Less dangerous, but also mixed effectiveness. Many of the observed critters will stick to the inside of hoses and other hardware, so draining won't get them all out. Unless you did a *sol enema as part of the fluid change, you would probably slow the growth at best, not stop it.
Sometime 20 years or so back in time I had a waterfilled bed (cool at the time), and there was some stuff that you poured in the water to kill all germs. You added a small amount of this stuff every couple of months.
One small bottle would last like 2 years for an entire bed filled with water, and cost was rather low. It should easilly be enough for a lifetime with water cooling computer systems.
It would be necessary to know what that stuff was made of. As I faintly recall, at least some of the water bed chemicals were clorine based - not compatible with WC hardware. However it is worth noting that one of the ingredients that I have seen mentioned as effective (It's part of the Airspirit coolant blend formula) is "Non-clorine / non bromine hot tub and spa sanitizer"
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efcoins:
If the alu is annodised or electrically insulated from the copper then it will not corrode.
WRONG! Those will slow the corrosion, but will NOT stop it! (note the specific mention of a Swiftech block failure above...) In the case of a Swiftech block, you have inherent connection between the Al and Cu since the Al top is screwed to the Cu baseplate!
Otherwise put a piece of zinc into the rad or res, then it will corrode instead of the aluminium.

WRONG again! Zinc is used in marine applications to protect STEEL not aluminum! There are charts showing corrosion potential, you can find them online. Per the chart, adding zinc will make your problem worse as the aluminum will sacrifice itself to protect the zinc.

I forget off hand, but I believe to do a sacrificial anode in an Al / Cu WC system you need to use magnesium. At any rate it isn't a practical solution.

Gooserider

efcoins · Post by **efcoins** » Thu Jan 15, 2004 7:03 am

Gooserider wrote:

efcoins:

Otherwise put a piece of zinc into the rad or res, then it will corrode instead of the aluminium.

WRONG again! Zinc is used in marine applications to protect STEEL not aluminum! There are charts showing corrosion potential, you can find them online. Per the chart, adding zinc will make your problem worse as the aluminum will sacrifice itself to protect the zinc. I forget off hand, but I believe to do a sacrificial anode in an Al / Cu WC system you need to use magnesium. At any rate it isn't a practical solution.

No corrosion is explaned at
http://www.terrific-scientific.co.uk/To ... sion-7.htm

The last paragraph talkes about protecting aluminium with Zinc

If the alu is .. electrically insulated from the copper then it will not corrode.
WRONG! Those will slow the corrosion, but will NOT stop it!

No, if the electrons can not get from one metal to the other then they will not corrode

silvervarg · Post by **silvervarg** » Thu Jan 15, 2004 7:54 am

Thanks for the good link Efcoins.
Wouldn't it be preferable to just attatch the zink to the rad instead of putting it inside the water?
Inless you have a big tank it will be hard to put the sink in the water without adding flow restriction (=more noise or less cooling). But attaching directly to the rad should solve things without drawbacks.

tay · Post by **tay** » Thu Jan 15, 2004 11:22 am

silverarg, iirc you are correct. They do something similar in cars, where 2 metals are joined so that one corrodes while the main body is kept safe. I cant remember from my chem class

herosformula · Post by **herosformula** » Thu Jan 15, 2004 12:10 pm

efcoins - look up "electrolyte" The water in your system is an electrolyte, and will transfer ions between the aluminum and copper, causing corrosion.

wussboy · Post by **wussboy** » Thu Jan 15, 2004 10:15 pm

Hmm...cool debate. Keep arguing! It's fun.

But as for me, I'm just gonna get a copper radiator and maybe do a dual loop system later (can't seem to find a decent copper HD waterblock). Thanks all!

silvervarg · Post by **silvervarg** » Fri Jan 16, 2004 12:51 am

Is the corrosion really a big problem in water cooling systems?
I highly doubt that all the parts inside the pump is made of copper.
So with every other part of the system is made of copper and insulated from chassi etc you should get corrosion inside the pump instead, right?

wussboy · Post by **wussboy** » Fri Jan 16, 2004 9:20 pm

I think the pumps are ceramic and plastic, so corrosion shouldn't be a problem.

Gooserider · Post by **Gooserider** » Sat Jan 17, 2004 8:43 pm

efcoins - I would reccomend you go back and re read your referenced site again (even if it is an example of dumbed down science) - they are talking about protecting an IRON structure in a MARINE application - just like I said earlier... (BTW lobster pots are normally made out of wood, and are required to have a structure that degrades so as to avoid the problem of 'ghost trapping')

For example, if we had an iron cage with steel mesh that we wanted to put in the sea to catch lobsters, we would soon find that it had rusted away. In order to prevent this, we could attach a piece of aluminium to the iron cage and mesh. Just like the aluminium foil attached to the nail, the cage would not rust, but the aluminium would corrode, pushing electrons into the iron cage and mesh and preventing it from corroding.

In reality, a metal called zinc would be used for this purpose (as it is even stronger than Aluminium). Sometimes a metal called magnesium is used (as this is stronger still). These pieces of metal attached to structures to prevent rusting are called sacrificial anodes - because they sacrifice themselves and corrode away to protect the structure that they are attached to. The metals used must be carefully selected - the anode must always be a stronger metal than the thing it is protecting, otherwise the electrons would flow in the opposite direction and the structure that you are trying to protect would corrode even faster! When the sacrificial anode has corroded away completely, it is simply replaced with a new one.

Note that the sacrificial anode needs to be electrically ATTACHED to the metals it is intended to protect, so just dropping a hunk of magnesium in the res won't do much. But it isn't practical to stick a useful sized anode inside the WB, so that makes the sacrificial anode approach difficult to implement at best in a WC system.

(In a marine environment, a sacrificial anode mightl be bolted to the hull if the hull is metal, but on a wood or fiberglass boat, the anodes normally come as collars that bolt around the prop shafts and / or to the rudders.)

silvervarg
Is the corrosion really a big problem in water cooling systems?

Yes it is in mixed metal systems if anti-corrosives aren't used (I've seen pix) however in non-mixed systems, especially with some anti-corrosives as insurance, it isn't. In mixed metal systems that use enough anticorrosives, and have them changed regularly, it's controllable.

I highly doubt that all the parts inside the pump is made of copper.
So with every other part of the system is made of copper and insulated from chassi etc you should get corrosion inside the pump instead, right?

As wussboy mentioned, the innards of our standard aquarium pumps are made from ceramics and plastics, with any metals (such as the drive magnets) encapsulated in plastic. Submersible pumps will also be either sealed or have all metallic parts encapsulated to prevent corrosion. Keep in mind that the common WC pumps were mostly originally used in aquariums and corrosion byproducts can be toxic to fish, so there is much design work in making sure that the pumps are corrosion safe.

Gooserider
[/quote]

silvervarg · Post by **silvervarg** » Sun Jan 18, 2004 6:19 am

Gooserider:
efcoins - I would reccomend you go back and re read your referenced site again (even if it is an example of dumbed down science) - they are talking about protecting an IRON structure in a MARINE application - just like I said earlier..

Checking out that site they clearly state metals in this order:
1) Aluminium
2) Iron
3) Copper
4) Solder
...
In reality, a metal called zinc would be used for this purpose (as it is even stronger than Aluminium).

So Zinc would do fine for protecting aluminium. Magnesium would be an even better protector, but less usefull in reallity.

As for lobster pots I know that they are mostly made out of metal. Next time I happen to pass by one when I go diving I will check if they use any sacrificial Anod. Even with an Anod they will corrode and gets destroyed as soon as the sacrificial anod has rusted away. Wood on the other hand will last a hugh time at the typical depths where you catch lobsters.

efcoins · Post by **efcoins** » Mon Jan 19, 2004 2:43 am

Thanks silvervarg

Jan Kivar · Post by **Jan Kivar** » Mon Jan 19, 2004 6:27 am

silvervarg wrote:In reality, a metal called zinc would be used for this purpose (as it is even stronger than Aluminium).

So Zinc would do fine for protecting aluminium. Magnesium would be an even better protector, but less usefull in reallity.

As Gooserider said, aluminium will corrode before zinc. But the thing is that while both of them will corrode (oxidize), aluminium forms a protective passive layer on the surface which will nearly stop the oxidizing. This is called anodising.

Whereas zinc will IIRC behave like iron, and corrode throughly, making zinc flake. Flaking would then clog the system eventually.

Note that I'm not 100% sure on this.

Cheers,

Jan

silvervarg · Post by **silvervarg** » Mon Jan 19, 2004 7:24 am

As Gooserider said, aluminium will corrode before zinc. But the thing is that while both of them will corrode (oxidize), aluminium forms a protective passive layer on the surface which will nearly stop the oxidizing. This is called anodising.

No, Aluminimu will not corrode before Zinc.

Here is a quick list of metals and there electrical values (e´n in volts) measured in seawater.

Gold (Au) +0.42
Silver (Ag) +0.30
Steel +0.05 (stainless)
Copper (Cu) +0.02
Tenn (Sn) -0.26
Lead (Pb) -0.31
Steel -0.46 (non-stainless)
Aluminium (Al) -0.51
Zinc (Zn) -0.86
Magnesium (Mg) -1.36

Any metal lower in the list will act as anod over a metal higher in the list and therefor protect it against corrosion.

Whereas zinc will IIRC behave like iron, and corrode throughly, making zinc flake. Flaking would then clog the system eventually.

I guess by attaching the zinc to the rad this would not be a problem.

Another simple and interesting technique is to add C-vitamins to the water.
The C-vitamins will remove all free oxygen in the water, and thereby stopping all corrosion. In most cases this is not practically possible, but if you have little free airspace and a tight system filled with desitlled water (=small amount of oxygen to start with) this should work fine.

Jan Kivar · Post by **Jan Kivar** » Mon Jan 19, 2004 8:19 am

silvervarg wrote:No, Aluminimu will not corrode before Zinc.

Well, here's yet another table...
http://www.overclockers.com/tips1041/
http://www.ocforums.com/vb/vb/showthrea ... did=154570

I think that most of the tables are based on seawater, whereas in the WC setup one should use distilled (ion-free) water with some additives.

Cheers,

Jan

silvervarg · Post by **silvervarg** » Tue Jan 20, 2004 2:59 am

Looking at the numbers there I think the value refered to in the links you provided are base on what happens in 25*C in open air.
I think the seawater based numbers would be a lot closer to a watercooling setup. Unfortunately I can not find any link the a site that has done any real testing on water-cooling equipment or even with destilled water.

Perhaps someone with a Cu-block and Al-radiator cound put on a piece of zink and connect up a multimeter to do some measurements, that way we would be sure to get reliable values (apart from measurement errors).

At the moment it seems that we are basing our assumptions on values that might not be correct in the realm that is interesting to this discussion.

Stupid Swiftech.

Stupid Swiftech.

hmmm