Chip on Aluminium Frame

campagsarge

I have a small chip on my aluminium frame (7000 series alloy) and want to patch it up before salt, water etc takes hold. Anyone able to advise me on the best way to go about this?

Anonymous

If you are not too bothered about appearance then cover the chip with clear nail varnish.
You could fill it with numerous dabs of modellers enamel (let each dab dry before applying the next then finish off with T cut) to get a colour match if you don't want it to show.

campagsarge

Thanks Anton, I will try and get the closest to celeste model enamel.

redddraggon

campagsarge wrote:

I have a small chip on my aluminium frame (7000 series alloy) and want to patch it up before salt, water etc takes hold. Anyone able to advise me on the best way to go about this?

Bare aluminium shouldn't be a problem, as soon as it exposed a thin Al2O3 layer is formed which is very unreactive which protects the Al metal underneath.

The Alumina layer won't go flaky like rust, and the permeability to oxygen and water is very very low meaning that the alumina layer won't grow thicker.

campagsarge

I knew I should have paid more attention in my science class! I guess this means that chipped paint work on an alloy frameset is ok - it wont rust the alloy underneath if left exposed as it will kind of self heal?

redddraggon

campagsarge wrote:

I knew I should have paid more attention in my science class! I guess this means that chipped paint work on an alloy frameset is ok - it wont rust the alloy underneath if left exposed as it will kind of self heal?

No, it won't rust:

Wikipedia page on Aluminium

From same page wrote:

Corrosion resistance is excellent due to a thin surface layer of aluminium oxide that forms when the metal is exposed to air, effectively preventing further oxidation.

So no problem with further corrosion of the frame, but the scratches might be a bit unsightly - for me that would be the only reason for giving the scratch a paint.

campagsarge

Thanks Redddragon, that's good enough for me!