I'm building small parts of aluminium (6086-T6) for use outdoors. I'm trying to work out how to best seal the aluminium but I'm struggling to find any information. I want to be eco friendly as possible so would ideally prefer not to plate or anodise if I can avoid it.

I was hoping that using Desmut then boiling the aluminium would be enough.

However, speaking to one company who both sells and anodises aluminium reckons that to prevent corrosion I have to anodise. Where as Gateros Plating says that desmut and leaving in the air is sufficient.

Any ideas or any professionals out there that can give me advice on this? I just don't want my aluminium to corrode.

Thanks