Quote:
Originally Posted by HarryT
Would there be any paint if it's bare aluminium? It looks like bare metal to me  . |
There ain't no such thing as a bare aluminium. Not for long outside a lab, anyway.
Aluminium oxidizes very quickly when exposed to the [oxygen in the] air.
So, the vast majority of aluminium parts are
anodized. A typical anodizing creates a [relatively] thick layer of porous Al2O3 (the same stuff that is called a saphire or a rubby when in the form of pure crystal). The oxide layer is then typically soaked in a dye and sealed in a hot water or by impregnation with a sealant.
It is very difficult to paint bare, un-anodized aluminium.
</off-topic> ;-)