View Full Version : masthead cutter design ?
frank smith
10-01-2009, 05:20 PM
Hi , I have been working on a small cutter design .
At this point I am thinking about the rig , and the amount of lead that should
it should . Also any input about the rig would be appreciated.
Frank
frank smith
10-01-2009, 05:24 PM
Sorry about that . I am interested the amount of lead it should have , I know that about 10% is a standard stating point.
Frank
Raggi_Thor
10-01-2009, 05:37 PM
It depends on your heeling angle and height of the rig.
Thats what turns the boat towards the wind and must be balanced with the lead.
lewisboats
10-01-2009, 05:38 PM
Yes and no...a lot depends on the hull shape, the keel design, the length of the hull (what is 'small'?) The more balanced the hull the less it changes the water shape as it heels and the less lead you need. A full long keel will need different lead than a narrow. deep, high aspect ratio keel. A small (less than say 20 ft) light weight skiff will change the water shape as you move around and will be more sensitive to weight change than to actual fixed lead of the centers.
Raggi_Thor
10-01-2009, 05:57 PM
Well, I think this is overlooked and mystified quite often.
Look at the boat from behind when it heels. You can estimate the arm between the sail's center of effort and the boat's center of resistance. Wide shallow boats have a short arm (or even negative) while narrow deep boats have a long arm.
12% to 15% would be typical, more if the rig is tall, the hull shallow and the appendages refined. Of course a sketch of your sail plan and hull profile would be helpful.
frank smith
10-02-2009, 11:32 AM
Thank for your replies , I am still in the planing stage but will put some info
in a usable form as soon as i can .
thank again
Frank
View Full Version : masthead cutter design ?