On Sun, 16 Nov 2008 20:59:50 -0600, Brian Whatcott
wrote:

On Sat, 15 Nov 2008 13:22:43 -0600, lowe210 wrote:

I know this is an out-of-the box type question, but has anyone had any
experience with or have any ideas or comments on the thought of taking
a standard aluminum pontoon boat and rigging sails on it? I know it
would be slow, but sort of looking for that old Spanish Gallion effect
(slow, steady, using no fuel). Any thoughts on how to rig it, connect
masts, and how it might sail? Thoughts on a keel(s) or other method of
allowing it to tack properly against the wind? Is this even a
possibility given the physics? Boat would be used on a large lake in
Texas.

A pontoon boat is in some ways ideal for sail propulsion. The hull
form is low drag forward, and high drag sidewards.
That's the good news. The wide base provides a good initial heeling
resistance without adding a deep keel.
But the bad news is handling the mast. If it is placed centrally
between the pontoons, some serious structure is needed to resist
the down load. Attaching the stays and shrouds is not such a big
deal, I'd think

Brian W

The normal support incorporates a jack strut and tension strouds
(dolphin striker) below the mast step. The bipod mast idea could use
a tension member between the legs to prevent spreading. It's doubtful
the original hull members were designed adequately to resist
spreading. The pontoons I've been on are fairly flexible between the
hulls. You could feel the deck twist when taking even small waves at
an angle.

Pete