Re: spar dimensions for small lugsail?
--- Inbolger@yahoogroups.com, "macinkos" <smacinko@...> wrote:
Hmmm, sailing an Auray -- sounds fun. As for scantlings, this might be
germane: I put a balanced lug on a Cartopper, and loved it! It was 64
sq ft, with a 9' yard and a 10' boom, both finished round and tapered.
The yard was about 1 3/8" at the thickest, and turned out a little
bendy for the flat-cut sail. The boom was maybe 1 1/4" at most and
worked just right. Turns out that the boom forces on a balanced lug
are much lighter than with a standard gooseneck type boom, because the
rig is inherently self-vanging. On a regular rig, most of the stress
is on the end of the boom, to pull in the upper leech and reduce
twist. With a balanced lug, this is largely done by the tension in the
downhaul and the luff (Make the luff _strong_!). If you put some round
in the head, say 1-2", you can use the downhaul to flatten the sail in
stronger winds.
I put two reefs in, with the second reef just below the throat, and
got a faux-lateen sail of about 35 sqft for big air. Worked great!
Good luck, and post some pictures when you're done.
Lynn
>Auray Punt...
> I am adapting a small balanced lugsail (yard 8'6"; boom 6'2") to an
Hmmm, sailing an Auray -- sounds fun. As for scantlings, this might be
germane: I put a balanced lug on a Cartopper, and loved it! It was 64
sq ft, with a 9' yard and a 10' boom, both finished round and tapered.
The yard was about 1 3/8" at the thickest, and turned out a little
bendy for the flat-cut sail. The boom was maybe 1 1/4" at most and
worked just right. Turns out that the boom forces on a balanced lug
are much lighter than with a standard gooseneck type boom, because the
rig is inherently self-vanging. On a regular rig, most of the stress
is on the end of the boom, to pull in the upper leech and reduce
twist. With a balanced lug, this is largely done by the tension in the
downhaul and the luff (Make the luff _strong_!). If you put some round
in the head, say 1-2", you can use the downhaul to flatten the sail in
stronger winds.
I put two reefs in, with the second reef just below the throat, and
got a faux-lateen sail of about 35 sqft for big air. Worked great!
Good luck, and post some pictures when you're done.
Lynn
The yard and boom on my Windsprint are 2x2 spruce with 1/2 x 1/2
reinforcing strips on each side to bear on the mast. The strips on the
yard are about 4 feet long and on the boom about 2 feet (or maybe 6"
shorter for each).
Patrick.
macinkos wrote:
reinforcing strips on each side to bear on the mast. The strips on the
yard are about 4 feet long and on the boom about 2 feet (or maybe 6"
shorter for each).
Patrick.
macinkos wrote:
> I am adapting a small balanced lugsail (yard 8'6"; boom 6'2") to an Auray Punt
> and am curious about spar dimensions. I understand the forces on the boom
> can be considerable but still wonder what that means in the context of this
> small sail.
>
> Any Windsprint owners out there care to comment? What size boom do you
> use and do you have any problems with flexing spoiling sail shape? My sail is
> considerably smaller than that on the Windsprint so I think your spar
> dimensions could represent an upper bound for me.
>
> Thanks,
>
> Seth
I am adapting a small balanced lugsail (yard 8'6"; boom 6'2") to an Auray Punt
and am curious about spar dimensions. I understand the forces on the boom
can be considerable but still wonder what that means in the context of this
small sail.
Any Windsprint owners out there care to comment? What size boom do you
use and do you have any problems with flexing spoiling sail shape? My sail is
considerably smaller than that on the Windsprint so I think your spar
dimensions could represent an upper bound for me.
Thanks,
Seth
and am curious about spar dimensions. I understand the forces on the boom
can be considerable but still wonder what that means in the context of this
small sail.
Any Windsprint owners out there care to comment? What size boom do you
use and do you have any problems with flexing spoiling sail shape? My sail is
considerably smaller than that on the Windsprint so I think your spar
dimensions could represent an upper bound for me.
Thanks,
Seth