This was really informative and clarified a number of issues that I have had question about so was a really great read.
Now I come to my point I have decided to do a west system 30 catamaran as my wife gets seasick and I want to take of around the world.
I have been sailing for almost 40yrs at 44 thats alot of my life.
I have also repaired re-decked help build all sorts of boats, and sailed even more.
Hence landing on a Cat after almost starting on a mono hull.
The problem is trying to find informative information regarding Mast beam.
Beams in general is very difficult.
And it'd be lovely to have an informative document like this available for a cat also.
I do understand that many purists have a major distaste for Cats but their practicality, speed and space for world cruising can not be argued.
So if you are inclined and do put together a page like this on Cats I will point every chat page and discussion group to it as it would be the only one on the net with suh informative information.
Regardless I will be using your site as reference material for my other builds and thank you very much for you great work..
Please let me know if you do a post re above at atw98(at)yahoo.com