every piece will be completely anodized. (once they are anodized, each piece will be seperated.

if YOU scratch that anodization(takes a pretty deep scratch, not something light), than that is no longer my problem, as it was you who messed it up.

look at dtek, they anodized their aluminum topped waterblocks.. do you see problems? no.

I don't own a dtek waterblock - I prefer not to mix metals in my water loop. What others do is their perogative.

SMan
I was addressing the 2 most ignorant posters in this thread
ignorance is curable, but it may take some effort
it seems clear you do not think, just gather opinions you feel are in support of your point
I am hoping geek will get an education

this topic has been talked to death on OCers, and here
search some: galvanic corrosion, cell corrosion, etc.
examples abound, there was a D-Tek al top on OCers, some really nifty nickle plated al on OCAU - look around

aluminum is a acceptable material, with appropriate precautions:
1) anodize it
2) ALWAYS use a corrosion inhibitor
and if you follow #2, you can skip #1; UNLESS you have a moist air environment (where the corrosion inhibitor cannot protect the surface - as a previous poster did make clear)

sound like your application ?

go learn something

I think you have a few options. in order of preferance

1. Make them out of brass
2. Nickle plate them
3. Type 2 anodize them

Personaly i feel that all 3 of those options offer acceptible protection but it is clear that others have higher standards than i do. If you make things to sell to the public you need to cater for them. Arguing the toss does not sell the caps! The way you will sell the most caps is by producing brass caps. This is the same reason that i have started making copper/brass waterblocks insted of copper/alu. Not because of my needs/oppinions but because i want them to sell and therfore you must choose the option that is most desirable to whoever is buying.

FYI i run an aluminium res with an aluminium cap. The res and cap are not anodised or plated in any way. When i take the cap off there is allways a few drops of condensed coolent on its underside. So far after 6months it has not corroded. Thats why i do not worry too much but it does not mean it cant happen.

ok, thanks.

the caps are anodized now, and corrosion should not be a problem.

I do know what I am doing, my family has been in the machining industry for several decades, and I've felt that unanodized aluminum is pretty safe in a watercooling loop, as I've never in my life have seen badly corroded aluminum. I may see spots of corrosion after several months/years, but those are preventative and removable by just using a 3m scotch brite pad to 'scrape' it off.

And in the years of experience, I've been suggested against nickel plating aluminum, as anodization is the only real way to go for aluminum.

dunno why they weren't made out of brass to begin with

does your res touch the case, out of curiosity?

if t-line touches case, and case touches copper rad, corrosion _will_ result

They were made out of aluminum because aluminum was on hand, I guess. Maybe it was free. Stang_Man then sells them cheap. We all win.

"Corrosion _will_ result" - well really vague tarnishing is about all the "corrosion" we're likely to see on sealed anodised. Of all places corrosion could occur, I'll take visibly through clear tubing on an easily washable part. We should hope the anode corrodes, because any galvanic corrosion on the anode plug is proof of corrosion protection in less accessible copper components. Why "protect" this component from performing a useful service?

My hot water tank has an anode plug, too. It's marked so. Perhaps I should take it out and send it to a plating service?

welcome Kobuchi, to those who post w/o knowledge

only magneisum, 99.9%, will function as an anode in a cu/al system

no. stick your anode where you will not forget it - your source of info

Harsh but ohh so funny/true.

I got a question, would Zinc be a good anode in these systems? (pleading ignorance here, but in the back of my head there is a nugget of info that says it is a good anode in galvanic corrosion environments. )

zincs work for a boat, but not for WCing
had one in my chiller with a ss bath and an aluminum Little Giant pump, the zinc did nothing

in terms of galvanic potentials pure magneisum is the only way,
but still far better to preclude corrosion of any sort due to the corrosion product

I surgested Zinc earlier, but to my knowledge this only applies when reacting with oxygen. and its not a sacrifical anode in that system, its just a sacrifical metal, because oxidises more readily then steel or aluminium.

Yes

and

Yes so does the rad

Maybe but will it attualy cause a problem? will it attualy be noticeible after the couple of years? So far the answer is no. i dont deny it happens but i dont relly see at as a problem in my case. When i building stuff to sell then it is a problem because there are a differant set of requirements. :dome:

That's a misleading statement. We were discussing the addition of aluminum to an otherwise copper system. In this case, a basic galvanic couple is formed. In any galvanic couple we use the terms "cathode" and "anode" to distinguish the two.

It's like labelling the positive and negative terminals in a circuit.

When you bring in a third metal, your knowledgeable statements about the relationship are true enough. Yes, magnesium trumps aluminum as the anode when all three metals are together.

To say this invalidates what I've said is like poking an earthed wire into a battery-powered circuit. Looks like all I've said about differences in electrical potential is "without knowledge".

Magnesium is used purposefully as an anode against copper/aluminum pairing. Why? Because when copper and aluminum alone are paired, the aluminum anode is sacrificed. So magnesium being way off on the galvanic scale takes the place of aluminum as the sacrificial anode.

Many water supply systems, where copper/brass (and plastic) are the only materials used, employ an aluminum rod as an anode. Its role is purely sacrificial. Without it there would be no anode, and the copper would corrode more rapidly (at the normal rate). Aluminum also trumps steel for the anode of copper, in case glazing on tank walls cracks.

When we're looking at a purely copper system, and we want a sacrificial anode just for the copper, an aluminum plug will serve. In our systems even anodised aluminum will do the trick.

Depends on how you look at it, since chemistry must ultimately deal in electrons. For example, you can call the oxidised (anodised) shell on aluminum a "semiconductor".

I should have been more clear....corrosion will result on unanodized alumnium.

okay, so copper is protected....

what protects your pump/wb from patriculate alumnium matter?

Simple user maintenence. Stang_Man's cap is easy to inspect and clean, unlike the innards of a waterblock. Scour the bottom if/when it appears tarnished. You can do that at the kitchen sink in half a minute, along with the pots. How clean is really up to the user. In any case, I think visible roughening of the surface wouldn't show for many years. Look at grandma's aluminum pans and other hard-use kitchen utensils - are they flaking?

Perhaps;

The point for me is, why the hell should you have to suffer possible problems over 25c of nickel, or perhaps $1 of anodization?

Forgive me for being blunt, but people will pay money for bling; its the simple magpie theory - its shiny, they want it. Nothing will stop them. Don't make them pay by having a substandard design.

Slater - difference is, you're probably using anti-freeze, right? my question earlier, shot down by billA and others, about using anti-freeze is right, in your case, but not when this item is subject to vapourised moisture (as you pointed out, yourself, lol).

Why the HELL should you have to risk your more than probably expensive pump for a 10$ t stopper? makes no sense at all to me.

A water heater tank has a heater in it... will this make it more electrically conductive, which would encourage corrosion? thus requiring an anode?

are they in contact with water and copper?

My grandma has stainless steel or silver-plated nickel utensils. :p

Why risk dirtying a facecloth when you can wrap it in plastic before use? Tarnishing of the cap is not a problem - unless scopic chunks of aluminum oxide are actually crumbling off - the corrosion of the cap guards against corrosion problems for the copper/brass. Maybe that's too much for the average customer to digest.
Good thinking. Galvanic corrosion in electric heaters must be complicated. I can't recall if gas heaters employ an aluminum anode. I guess they could...

However, a basic rule in galvanically corroding pairs is that the cathode will corrode more slowly than by itself. So why not apply that. Add aluminum to an otherwise copper system, the copper is protected.
The tailpipe in her stainless sink is brass, if not the whole drain system. The water flows out of copper pipes, and may even be green from that. She likely soaks aluminum with various metals and solvents... I don't know. We want a real world answer to this question of how much corrosion, and unfortunately only time has the answer.

I am no expert on galvanic corrosion, nor will I claim to be one - but it seems to me that this issue was settled long ago:

I don't see anything really arguable there - you can argue anodes for a boat or a gas fired heater, but that has little bearing on Watercooling in this case

Neither I. But just read off the top of Google, and you'll understand more than most.

Google: galvanic corrosion

And here's a brief explanation I like to believe is correct.
The fellow who posted that learned something since then. That's why he abandoned his statements.
Why? :)

***

What are we trying to accomplish here? If your objective in watercooling is to keep the aluminum cap looking new, then sure coat it or whatever. Good enough. If you think minimising tarnish in a copper waterblock more important, then I suggest sacrificial aluminum, scrubbed off from time to time.

The thing is, we are not dealing with systems in which the copper or brass will corrode. There is not point introducing a metal that will corrode and put stuff into the liquid. There is no poin gunking up blocks, pumps and radiators to have a fancy looking T line cap.

I agree pippin88. Honestly I'm not really concerned about some scarcely perceptible oxide on my copper components. It can't be effecting performance much.

Case in point, that Swiftech block all rainbowed with oxide from brazing. A splash of pickle would have cleaned it up, but apparently the oxide is immaterial, or doesn't effect performance enough to justify a cleaning. So if that's true then surely there's no point trying to slow lesser tarnishing with a sacrificial anode.

the thing is, the caps are anodized and they will not corrode at all now.

unless someone is stupid, and deeply scratches one of the caps, well that then is beyond my control.

bill, yes I understand what your saying, sure it can corode and get nasty I have put a peice of copper and aluminum in a jar for a year and there was no chunks but it did get gross, that was when they were submerged together.

Yes I totally agree, Brass would solve the problem 100% and not cost much more like I have said.

So why am I ignorant now? explain bill:)


Jon