Class Acceptance of Square Tube Framing

You're going to have to define what you mean by "state of the art" aluminium...and also its intended usages too.

 

A 40 to 45 foot cruising catamaran. I worked in an aluminum yard years ago (cut frames), and imagine it's mostly the same today. But when I hear about RHS (wich we never used), flat bulb, etc. I wonder how those are being used and what else is out there? Thanks again Ad Hoc.

 

Blockhead

Basically you will be using alloys from either the 5000 series (plate) or 6000 series (extrusion). Any other ignore. Some have dabbled in the 7000 series but ended up with significant corrosion allured by the higher strength.

So if you're talking about extrusions and i do not mean the expensive and simple shape 5000 series (yes some do exist), then you're always going to be using 6000 series. In this case always go for 6082, and the temper you want, really depends upon how much strength and ductility you want, ie how "bendable" and if the strength is an issue for you.

The bendability, if you like, depends also upon the radius of curvature you're tyring to achieve and what tools you have for bending.

 

From Ad Hoc

It so true, and perhaps the most difficult. It is so easy to be taken by a shape or material and trying to bend the logical rule to make it fit.
It is I think the reason of the disappearance of the ferro cement. An extraordinary material, completely taken over for the wrong reason and finally killed by the one who promoted it due to lies and incapacity to make it work for the real reason. Ferro cement still in use by highly trained building engineer for complex shapes. The material is not bad, the designers were.

 

Thanks All.