Aluminum finish question.

[CowboyKell]

The only Aluminum work I've done was either hidden or painted. I want my TD to have unpainted AL. I will be going with either 5052 or 6061 depending on the advice I get here, price and availability.
So what is the best finish to look for? What have ya'll used?

[citylights]

Any local steel supply shop should have it. Mine was $50 per 4x10 sheet of 0.04 5052 aluminum at Curtis steel in Las Vegas. They had it in stock. They could have ordered 5x10 at $75 per sheet, but I went with the 4x10 in stock and cheaper. I will have a couple extra seams in my roof because of that. Sweet stuff, bends easy. I cut mine carefully with wood blades in jig saw and router. (Wear eye protection!). I also ordered a bunch of one and two inch angle from them for trim. Not sure what thickness everyone else is using, but I went with 1/8th inch thick.

I also ordered dead soft door and edge trim from http://www.lilbear.teardrops.net/parts.html in Reding CA. Expensive, but great for the specialty trim.

Also use stainless steel screws. They are a wee bit expensive but recommended to not corrode with the aluminum.

Use butyl tape under the trim to seal the seams.

I just posted some pictures of my aluminum skin work in my build journal.

I have tried to work with sheet metal before. That was hard. The aluminum has been a pleasant surprise. Easy, so far...

Good luck!

[aggie79]

My 2 cents worth - if it is available and within your budget, I'd recommend an anodized finish on the aluminum.

The anodized aluminum will greatly minimize staining and discoloration especially when exposed to weather. It is stiffer and a little harder to work than non-anodized but I feel it is worth the effort. The anodizng will add to the cost though.

There are many types of anodizing. I believe the aluminum I used was called "bright clear" or "mirror bright". It is not as shiny as polished aluminum, but I don't have to maintain it. It looks as good today as when I installed it four years ago. I bought the aluminum from a place that sells materials for fabrication of signs.

[jonw]

I second the anodized aluminum. It will look good with little maintenance.

I wouldn't recommend 5051 unless you plan on painting it. It easily dulls and shows every dent and stain (think bird poop and squashed bugs). It is easy to work with, though.

I used .040in 5051 and eventually painted it with auto paint.

[KCStudly]

Aggie79's aluminum also came out very nice because he left the protective shipping film on for as long as he could (until the great reveal). Ask about protective films. I'm sure it is an up charge (unless it comes automatically with the anodized), but it will surely help cut down on scrapes, scratches and finger prints.

[CowboyKell]

Just spent several weeks with the airplane building side of the family in Texas. They are recommending 6061 in .032 thickness and a T6 hardness. This is basically the same skin that's on American Airlines planes and it stays shiny for years with minimal upkeep. That is until you look up close.
I am leaning towards the anodized bright finish. If I can find it reasonably priced.

As far as stainless screws...I have spent many years racing sailboats and seeing stainless hardware in contact with Aluminum. Its not pretty, lots of galvanic corrosion. But that is in a very harsh, wet and salty environment. Probably not that big a problem on a trailer. Even so I am most likely going with aluminum rivets and drive nails that will look like rivets.