How to preserve badly corroded aluminium.

[axelford]

Hi I have some pieces I made the mistake of removing from a creek and they were badly corroded already but some are now flaking apart a bit, any ideas how to slow down the corrosion or preserve the bits?

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[saratoga]

Oxalic acid will remove a lot of the corrosion, so then it just a case of keeping it dry and monitoring any further corrosion.

[axelford]

Thanks, by remove corrosion do you mean it will fall off or dissipate?

[saratoga]

It will fall off, leaving the pocked, pitted surface clean.

[baronbeeza]

Most of an aircraft is made of alloy and we get some rather unique corrosion characteristics, especially with the common copper alloys, 2024 and 6061 and the likes. It sounds like you may have exfoliation or inter-granular corrosion if bits are dropping off. I would spray the fitting regularly with something like Inox or ACF50. I use lots of Inox and there would hardly be a day go by without squiring something. The aircraft get it everywhere.

[grgrimmer]

Yeah, I would vouch for what baronbeeza says. I use ACF-50 (can find it on Trade Me) and it is not only good for that, it's great for any electrical/electronic connections that have doubtful connectivity problems. Motorcycle enthusiasts swear by it as it solves most of their electrical problems. It's quite pricey but well worth the money.

[axelford]

Ok, $38 dollars on trade-me isn't bad, although I'm not using these parts in a plane just preserving them.

[axelford]

So just to double check, Acf-50 will hold the remaining metal together and the rust won’t fall off it’ll just not get worse?

[baronbeeza]

Sept 7, 2019 16:12:01 GMT 12 axelford said:

So just to double check, Acf-50 will hold the remaining metal together and the rust won’t fall off it’ll just not get worse?

If you can post a pic we may have more of an idea and offer some better suggestions. ACF50 will stop any further damage if the item is just on static display.


I buy this stuff, 5 litres a time from Supercheap. We use it daily on all manner of applications.

www.supercheapauto.co.nz/p/inox-dewatering-fluid-300g/1000.html

[grgrimmer]

Watch this video and it will show you it's capabilities:

[oj]

Sept 1, 2019 18:10:20 GMT 12 baronbeeza said:

Most of an aircraft is made of alloy and we get some rather unique corrosion characteristics, especially with the common copper alloys, 2024 and 6061 and the likes. It sounds like you may have exfoliation or inter-granular corrosion if bits are dropping off. I would spray the fitting regularly with something like Inox or ACF50. I use lots of Inox and there would hardly be a day go by without squiring something. The aircraft get it everywhere.

So you have quite a few offspring then?

[axelford]

Thanks Grimmer, that sounds like it does exactly what I want it do.