Insulating aluminium to prevent corrosion

[kaku]

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.



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.

 

[kaku]

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.

 

[kaku]

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.

 

[kaku]

Final post from me on this and I'll stop hi-jacking 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.