Subject: [harryproa] Re: Calculating hypothetical performance |
From: Mike Crawford |
Date: 12/10/2008, 8:24 AM |
To: harryproa@yahoogroups.com.au |
Reply-to: harryproa@yahoogroups.com.au |
<<A 12 m mast on a 2 m stub (plus the length that's buried in the
hull) should give you the sail area you're looking for >>
Nice rig.
That's similar to how cat2fold's rigs work. Although they are
una/wyliecat type rigs, the mast design is similar. A stub sits in the
hull and the mast (in their case) slides into the stub. You could also
slide onto the stub, depending upon how you want it to work.
While I'm not about to spend $200K for the boat, I do like what
they've done in some areas. Plus they have sailed it for a few years,
so the design is at least partially tested.
If you go with a single mast, the MI-6 rig with jib would certainly
be handy in reducing the sheet loads while also adding a nice bit of
sail area.
- Mike
nonsum_pisces wrote:
--- In harryproa@yahoogroups.com.au , "Gardner Pomper" <gardner@...> wrote:
>
> I could match the screacher based sail area if I had telescoping masts, or if I had a double ballestron rig. Any feedback on those two choices?
>Hi GP,
The balestron rig minimizes sheet loads, reducing hardware, weight and cost. You might consider something like the MI-6 rig which is designed to be in 2 parts. A 12 m mast on a 2 m stub (plus the length that's buried in the hull) should give you the sail area you're looking for with a fully battened elliptical main and a small jib. This provides a single rig that will break down to fit in a shipping container that's easy to handle, light and inexpensive; all relatively speaking of course.
Jim Michalak has info on sail calculations, righting moment here:
http://www.boatbuilding-links. de/Jim-Michalak/ sail-math- and-thoughts- of.html