Wishbone
The full wishbone makes a lot of sense. I'm not sure I'd go with it
because it would add some complexity and make and covering the sail a
bit more of a hassle than a fixed boom.
I'm also considering a furling boom. I wouldn't consider a furling
mast because a failure with the furling mechanism could spell doom.
But a broken furling boom would still be fully functional.
But furling issues aside, the Wyliecat folks have had good luck with
their wishbone design, and would probably say that reefing and covering
the sail are non-issues.
http://www.wyliecat
That half wishbone, though, worries me. Either it's going to
interfere with the sail, or it's going to add a huge point of
concentrated stress on the mast. Why add the stress? It's the same
reason the Hoyt rig bothers me. Sure, it works, but there are all
sorts of weird torsional stresses on right-angle joints. I might be
happy daysailing with a rig like that, but I wouldn't want to leave
sight of land.
The full wishbone would just put a point of compression on the mast,
making for a much simpler design. If the mast is strong enough to
handle the other sailing loads, the boom load wold probably be a
non-issue. In fact, if you look at the Wyliecat rig, you'll see that
the wishbone "floats" on lines and isn't attached directly to the mast.
The easyrig and una rig with fixed boom also are simple in that the
stresses are all direct and easy to design for.
Circle
Stress in boats likes to concentrate at corners, and circular windows
and hatches are the best ways to avoid these corners. That's one
reason why you often see round hatches and inspection ports, as well as
rectangular ones with well-rounded corners.
The solitarry is an extremely lightweight boat with just no extra
structure anywhere. Where a cruising boat might have enough extra
resin and matrix to handle extra stresses, the solitarry is going to be
as light as possible. A round escape hatch would help reduce corner
stresses, and therefore reduce the structure required to handle them.
- Mike
Gardner Pomper wrote:
Hi,
I was just http://www.sponbergyachtdesign. looking at his wingcom/
masts. The idea of a stub mast with the wing mast rotating on it
appeals to me for my containerizable boat, so that I can get more sail
area. Will this work with your mast build methods and bearings? I like
the sound of your $350 bearings alot more than his $5000 bearings.
Also, what about his idea of a half-wishboom boom? If I angle the boom
up like that, I could have the clew above the hardtop over the ww
hull, and still have the sail low enough to work on at the lw hull.
Still thinking...
- Gardner
York, PA