How many people here run mixed metal loops?

[JCLW]

In particular systems with both Cu and Al components.

- What precautions do you take against galvanic corrosion? Additives? Sacrificial anodes?
- Are your Cu/Al components electrically bonded together? Electrically isolated? Or just in there/haven't paid any attention?
- Has anyone personally had any problems?

I'm looking at a setup using:
- Swiftech 6002 CPU block (copper)
- DangerDen Maze4 GPU block (copper)
- Hardware Labs Extreme II radiator (copper)
- Swiftech (plastic)

On top of this I'm thinking of custom fabricating an Aluminium (5052 marine grade alloy) resevoir/case unit to house the pump and radiator but I'm a bit concerned about using both Al and Cu components in the same setup. Any thoughts?

[Doomer87]

i currently use a D-tek White Water block with an aluminum top. During the last 2 times i've changed the water (i change it about every 6-9 months), i found a bit of white colored residue left in my clear bay res as well as clearflex tubing stained white. I use a valvoline coolant additive that claims to prevent corrosion as well as lubricate the pump to reduce wear.

In the past i've actually used an aluminum reservoir with my maxijet pump submersed in it. The reservoir was anodized black to help prevent corrosion.

All in all i dont think a mix of aluminum and copper in a rig will cause too much trouble as long as the aluminum is anodized and you use some form of anti-corrosion additive. I use about 2.5-3 liters of distilled water in my setup and about 5-10% anti-corrosion additive and i have never had any of the horrible corrosion trouble reported by some of the members in this forum.

I wouldnt recommend using a bare aluminum reservoir in your setup... that will most likely lead to another horror story.

[Sneaky]

i'm running a loop with silver & copper in it :p

[ZachM]

I am using a D-tek White Water with an anodized aluminum top. I run in between a 15-20% Prestone Dexcool antifreeze to water mix with a litte bacteriostat thrown in. I'm not sure on the exact percent because I had to add a little water, and antifreeze after I added too much bacteristat. :p

I have run about 20% antifreeze in the past though, and have experienced no corrosion problems. Though the anodizing probably helps a lot compared to bare aluminum.

[calvin]

Aluminum res* with submerged pump ~3 yrs
Copper cpu block
Coolant - 90/10 distilled/Prestone
Any corrosion observed - none

*res surface finish = powder coating

[voigts]

You really don't want to go with bare aluminum. That is a mistake.

I have been running two anodized aluminum hard drive coolers for about 7 months with no corrosion. I use about 10% antifreeze with iodine and some algaecide.

[Polonator]

i'm running a loop with silver & copper in it :p

Yes Mr. G5 man. ;)
So what does the mix of silver and copper do? Similar electrochemical properties to a mixture of copper and aluminum?

[Voodoo Rufus]

I've run mixed metal, an anodized aluminum Swiftech block and copper/brass radiators, and never had a problem using just water wetter.

I see no problem with mixed metals as long as you do use antifreeze or something to prevent corrosion.

[jamesavery22]

You really don't want to go with bare aluminum. That is a mistake.

I have been running two anodized aluminum hard drive coolers for about 7 months with no corrosion. I use about 10% antifreeze with iodine and some algaecide.


Ran a bare copper (mcw6000) and bare aluminum (transmission coolers) for 6months + with a distilled + 20% AF + cap full of iodine and had no issues. Nothing but some crud I needed to clean out of the coolers in the coolant when I drained it.

[rogerdugans]

I have run mixed metals a few times- copper/anodized alum blocks and aluminum and copper radiators, mostly.
I normally used distilled water with a small amount of water wetter (approx. 3%) and a small amount of antifreeze (approx. 5%) and had few problems: a few minor deposits and pitting, here and there, but never anything that would require taking a component out of service.

I currently have a system running with copper, brass and stainless steel and in the 9 months or so it has been running I have had no trouble.
In this system I ran with straight distilled water for the first 6 months and had no issues. Now a large portion of it is buried outside, so in preparation for winter I am running with a much larger concentration of antifreeze than I normally would- about 20% currently.
As winter draws near I plan to increase to near 30% antifreeze.

One note on antifreeze as a method of reducing corrosion: these components of the antifreeze are consumable, so the fluids need to be periodically changed, just like in a car. I have not yet seen any info on just how often this should be done though.....it doesn't say anything about computers on my jug of Prestone. ;):D

[nikhsub1]

Yes Mr. G5 man. ;)
So what does the mix of silver and copper do? Similar electrochemical properties to a mixture of copper and aluminum?
No, silver and copper are 'like' metals, they are very close on the noble scale with silver being a bit more noble than copper. FWIW, the mix of silver and aluminum is ever worse than copper and aluminum.

[johan851]

One note on antifreeze as a method of reducing corrosion: these components of the antifreeze are consumable, so the fluids need to be periodically changed, just like in a car. I have not yet seen any info on just how often this should be done though.....it doesn't say anything about computers on my jug of Prestone.
I don't think it's much to worry about. Most watercoolers end up doing some kind of modification to their system often enough to not have to consider changing fluid out. I can't see it being more often than once a year, if that. Our loops (loops like dugans' being an exception) generally don't contain a lot of metal in the first place.