Thickness of aluminum cat hulls

[JonathanCole]

If I am using type 5052 H32 Aluminium/magnesium alloy to build catamaran hulls, is .125 thickness adequate for a robust hull, assuming all curves, and bulkheads at a minimum of 5 feet on center? Also, can this material endure without coating it?

Also posted on metal boatbuilding forum.

[CDBarry]

What do you scantling calculations tell you?

[JonathanCole]

I can't find a precise definition for "scantlings". Where's that BoatDesign.net glossary? Can you explain scantlings?

[D'ARTOIS]

For your purposes Jonathan, 4mm minimal thickness is required, 5 mm would be better. The hulls are stiffened in the longitudinal way sufficiently by the top mounting bracket and the long rubstrake along the hull.
Since those hulls have to carry only weight distributed over the whol length, more reinforcements are not required save for some bulkheads to keep you afloat at a collision. And there have been taken provisions for.