Insulating aluminium to prevent corrosion

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Having given up hope of being able to grab a Swiftech Apogee Drive II, I decided to pick up Barrow's LTPRK-04 CPU block/pump combo for a mini-ITX build I'm working on.

It looks great, but with a single huge oversight: the pictured blanking plate used to seal the side of the reservoir is made of uncoated aluminium (I confirmed continuity with a multimeter) and is in contact with the coolant. The cold plate is nickel-plated copper and the rest of the loop will be similar - so there's a risk of galvanic corrosion.

RoaxLxT.jpg

I've considered making a new plate out of POM or similar material, but it would great if there was an easier option. I've thought about coating the coolant side of the plate in teflon or liquid tape but I'm uncertain about longevity and if it will still seal reliably with the O-ring.

I realise it's pretty niche, but interested to hear if anyone has any experience or knowledge on the topic.
 
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I guess they had to blank it to get access for machining the waterways.
How about trying to annodise it? I think it can be done at home. But you're likely to find somewhere to do it for you. Could get it a custom colour to match your build.
 
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Have you actually unscrewed the plate to make sure it makes contact with the coolant and isn't just a bling cover?

TBH You'll probably be fine as long as you use decent coolant, most of the horror stories about aluminium parts you hear from back in the day involved people running their loop on tap water or dodgy "specialist" fluids. Most loops actually contain either aluminium or equally dissimilar metals it's just the owners don't realise because their coolant inhibits corrosion and they don't know about the aluminium/steel in their pump or the tin flux in their radiator.
 
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Yeah it definitely contacts: there's two rectangular O-rings inside - one between the leftmost 'square' of screws for port C and another between the rightmost square covering ports B and A.
The loop is going to be using EPDM tubing so I'd rather sort it now - any corrosion/deposits that appear probably won't be noticed until it's too late.
 
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Optimum Tech just did a review on this and there was no mention of the aluminium.

https://www.youtube.com/watch?v=SBIWgKmwr68

I think Optimum Tech produce great looking videos but to be honest they're not a great source of detailed or technical information.

I've pretty much decided to just fabricate a new part. There's a little while before the next generation of graphics cards are available so it's not like I could finish the loop sooner than that anyway.
 
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I scoured the comments and couldn't find anyone commenting about it either.
Doesn't sound like a bad idea. Get a piece of annodised plate, and cut it to match the existing one.
 
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How sure are you its actually in contact with the water? Chances are its there for aesthetics, i.e machined to do the ports and such and then blanked off with the plate and plastic/o-rings. I would have thought they would state and or not use aluminium if it was in contact with water and could be mixed with other metals etc.
 
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@kaku did you make any progress on the plate at all? I was wondering if following your discovery about that, whether you were concerned about / aware of the material that the jetting fins inside the block itself are made of and whether they are likely going to suffer from a similar issue.

The reason I ask is that I've just picked up one of these blocks as a means to dabble in the watercooling world, but seeing the above I'm now a little apprehensive that I'm setting myself up for a disaster down the road.

Edit: Did some actual reading beyond "oooh look shiny block" that the base is nickel plated copper so that's all good. Still interested to see how you're doing with the plate at the top though :)
 
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How sure are you its actually in contact with the water? Chances are its there for aesthetics, i.e machined to do the ports and such and then blanked off with the plate and plastic/o-rings. I would have thought they would state and or not use aluminium if it was in contact with water and could be mixed with other metals etc.

The holes in the block are O-ringed, but not covered with plastic. That plate will be in direct contact with the water. I'm speaking with someone at the moment from a certain watercooling site, based in the UK, and they've said they seem to think it's anodized. I've followed up, but trying to get some more info. Also discovered that I seem to have a little screen on my version, I think I was sent an upgrade by mistake!
 
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Final post from me on this and I'll stop hi-jacking :D I contacted Barrow directly and they came back to me to say that this panel at the top is actually stainless steel, not aluminium. Based on a quick search, that seems to indicate that any copper in a loop would be corroded, compared to it being an aluminium plate, where this would corrode instead.

Neither are ideal of course, but wanted to drop that in here, in case anyone else starts searching for the same thing and it can help someone else out.
 
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Final post from me on this and I'll stop hi-jacking :D I contacted Barrow directly and they came back to me to say that this panel at the top is actually stainless steel, not aluminium. Based on a quick search, that seems to indicate that any copper in a loop would be corroded, compared to it being an aluminium plate, where this would corrode instead.

Neither are ideal of course, but wanted to drop that in here, in case anyone else starts searching for the same thing and it can help someone else out.

I came to the same solution (ended up checking with a magnet) - could have just contacted Barrow in the first place!
Not as bad as aluminium, but still far enough apart according to Wikipedia's anodic index chart to make me uncomfortable. I'm going to make a copy of the part using Delrin/Acetal.

I think I'm being overly cautious - my old D5 pump's body is stainless steel and in contact with the coolant along with copper blocks, but I've never had a problem with corrosion or gunking.
 
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I wish I'd checked as well, didn't really occur to me until it was too late. I've sidelined my build for now so just returning the pump for the time being until I'm less busy and can look at it again. Good luck with the build!
 
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Stainless steel is used very often in water cooling. Look at EK's and Alphacool's line of blocks for Strix cards for example, those plates cover the micro-channels that jump over caps and VRMs. Stainless steel is not an issue with bare copper or nickel plating.
 
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Stainless steel is used very often in water cooling. Look at EK's and Alphacool's line of blocks for Strix cards for example, those plates cover the micro-channels that jump over caps and VRMs. Stainless steel is not an issue with bare copper or nickel plating.

That's useful to know, thanks LePhuronn :) Being as new as I would have been, I wanted to make sure I started off on the right foot, and for me at least I just Googled my way into a bit of a hole. There's almost too much in the way of x is bad, y is worse etc... such is the way of the internet!
 
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Most PC cooling fluids have a low conductivity, and so because this is the only conductive path in a normal system, galvanic corrosion is minimized. Provided no current flows then there is no corrosion.
 
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