Anodize or not

[Sonetpro]

I am ordering my aluminum and think I am going to order anodized. It costs 25% more but I think it would weather better. I frequent the beach alot. Any thoughts?

[SteveH]

I think it would weather better also...especially at the beach!

[WarPony]

I was reading on anodizing and when aluminum is anodized, it makes it surface hard. I don't know if it would weather any slower or not but if you are planning on using anodized trim I would think making bends is really going to be difficult. I suppose you could anneal it for the bendy parts but then you'll just be wasting money for anodizing by annealing it and taking the hardness out. I guess it just depends on what you are using it for.

[angib]

Warpony,

Anodising only affects the very surface layer of the aluminium - about 0.1mm (4 thou). It doesn't seem to make it any harder to bend - and the anodising doesn't seem to crack when the aluminium is bent.

There is a separate process called 'hard anodising', which can only be a sort of browny grey colour, that is a lot harder than normal anodising, but it's still only a very thin layer.

Steve,

The only downside of anodising is that any marks that you do get will be pretty much impossible to repair or cover up.

This is unless you start cheating - making black anodised aluminium boat masts, we were plagued by tiny little handling scratches that showed up. We used to deal with them with 'instant anodiser'. Now, to an amateur, that would look like a black felt-tip marker - of course, that was just a handy case in which to keep our trade-secret instant anodiser....... Honest.

Andrew

[WarPony]

Warpony,

Anodising only affects the very surface layer of the aluminium - about 0.1mm (4 thou). It doesn't seem to make it any harder to bend

Ah, I didn't know that. I figured it was like pie crust....... if it bends, it breaks.

[Sonetpro]

From what I read on SAF when they process it it actually becomes part of the metal.
Quote from site.
"What is anodizing?
A coating of aluminum oxide is grown from the aluminum by passing an electrical current through an acid electrolyte bath in which the aluminum is immersed. The coating thickness and surface characteristics are tightly controlled to meet end product specifications. "