Thread: Aluminium and corrosion

Remove it, sand it, prime it, paint it...

Apply some compound between it and the frame before refitting...

Use etch primer on the aluminium, otherwise all the paint will all come off again eventually.

Originally Posted by Tombie

Remove it, sand it, prime it, paint it...

Apply some compound between it and the frame before refitting...

Thanks for that Tombie and Spel. I removed it, sanded it, primed it with etch primer and I have painted it.

What I now need to know is the type of compound to use where the steel bolts go into the cast aluminium. Is there a special stuff like Locktite?

I would use a copper grease on the threads and shift of the bolts as a rust inhibitor and isolator
Regards

Hi,

There is a yellow lithium based paste in a tube used specifically for this purpose in yacht rigging............. prevents corrosion of aluminium in contact with stainless.

Can't recall the name, but a chandlery will stock it.

cheers, DL

Duralac is one type of compound which is quite good.

https://www.whitworths.com.au/main_i...AbsolutePage=1

Originally Posted by strangy

Duralac is one type of compound which is quite good.

https://www.whitworths.com.au/main_i...AbsolutePage=1

X2 we use it all the time where we have stainless and alloy on the trawlers, never had an issue once duralac is used.
I have seen alloy completely corroded away from it being bolted to stainless. If you are really stuck and need something make a gasket between the 2 surfaces from a plastic milk bottle.

Cheers Ean

Definitely don't use a copper based anti-seize in contact with aluminium. It's OK for steel-on-steel, but will accelerate the corrosion on aluminium.

+1 for Duralac