any aluminium experts out there?

[Dokkodo]

Apologies, this is part of a scatter bomb of posts pertaining to a project (tiny home on wheels, in project forum)

im ordering about 50 sq metres of aluminium cladding, through the metalworking firm next door.

i have the choice between 1050 (standard) and 5082 (marine) grade - with a just-less-than 30% difference in price, marine being dearer obviously.

wondering whether anyone has advice one way or t'other, i dont neccesarily need to scrimp on such a vital component, but obviously savings would be good whereever possible, so im wondering whether the corrossion resistance and increased strength are worth the expense, seeing as mine isnt strictly a marine application, more of a plain old exterior one. This website would seem to suggest that it is good in transport applications, and anything that aids structurally would be good. So basically im wondering whether its worthwhile in my case (essentially building a caravan/air stream type thing)

any wisdom much appreciated cheers!

 

[TFrench]

All the external aluminium cladding we do (industrial pipework/tanks/ducting) is 1050.

 

[HappyHacker]

I am not an expert but know that aluminium does not like salt which eventually corrodes it. The marine grade has a higher resistance to salt.

So whether the extra expense is worth it depends if you are going to keep it near the sea or use it on salted roads.

Also watch out for letting aluminium contact other metals as the galvanic effect can cause corrosion as poorly installed aluminium Land Rover wings have proved if not isolated from the steel supports.

 

[Dokkodo]

ok great thanks, i dont plan to live by the sea and i defintely dont plan on towing it if the roads are at risk of being salty and icy, sounds like if 1050 is good enough for industrial applications itll be fine, and they look exactly the same, so ill spend the money on a bandsaw!

 

[Fitzroy]

I’d reinforce what HH said, aluminium is one of the least noble metals in the galvanic series and it will corrode very quickly if you set up a galvanic cell with just about any other metal.

Fitz.

 

[profchris]

Glider trailers often use aluminium bent over hoops, and I'm sure they use the cheapest grade. They sit out all year long in exposed conditions, and I've seen trailers which are 30+ years old and the aluminium is still fine. The steel parts rust away of course, but the aluminium keeps on going!

 

[Dokkodo]

I’d reinforce what HH said, aluminium is one of the least noble metals in the galvanic series and it will corrode very quickly if you set up a galvanic cell with just about any other metal.

Fitz.

Does that include stainless?

 

[chaoticbob]

I’d reinforce what HH said, aluminium is one of the least noble metals in the galvanic series and it will corrode very quickly if you set up a galvanic cell with just about any other metal.

Fitz.

Does that include stainless?

Yes it does - I have a cheap stainless pan had which had handles attached with aluminium rivets. They didn't last long.
Robin.

 

[Dokkodo]

hmm ok, was planning to use stainless screws and epdm washers (with or without galvanised steel attached) to fix the ali sheets to the frame. guess if i give the holes in the ali clearance then therell be no contact, will just need to be sure ive got the holes well sealed.

on another note, getting the spray foam insulation to adhere well to the inside face of the ali - this might be even more specialist knowledge, but does anyone know the best way to prime for this? its either acid etch or epoxy i think, but im struggling to find a clear answer. I just emailed 3M, guess if anyone knows about sticking stuff to stuff itll be them...