Re: 120 degr angle

Posted by michel.capel (michel.capel@…>)

Lance, I don’t know if you have any, but staysails are really
helpful on these angles of sail if it’s blowing under 20 kts. I just
ordered a standard sized all-round (i.e. medium full, for 90* - 150*
apparent wind) gennaker with sock to use as a mizzen staysail. These
ready made sails are competitively priced and fit fine.

Alternatively, you could try and find a second hand spinnaker and
have the leech shortened with 3 or 4’ to change it into a gennaker.
That will result in a full headed sail, very good on courses of
120* - 170* apparent wind. As a general rule, you could aim for a
sail with about the same area as your main and mizzen together.

Even your full displacement F40 can be persuaded to fly with one of
these sails!

Michel


— In freedomyachts2003@yahoogroups.com, “lance_ryley”
<lance_ryley@…> wrote:

Thanks - for me, that was really the only point to the exercise -
to
see if I could make Excel plot a polar graph. I already love my
boat
and don’t need the numbers to tell me that. Although they may come
in handy next year when my wife and I do Marblehead to Halifax -
not
as absolutes, but over a distance race like that, knowing, for
instance, that the fastest point of sail for the Cat Ketch seems
to
be around 120 degrees off true wind angle might help to minimize
the
time between showers.

Bright Star

— In freedomyachts2003@yahoogroups.com, “michel.capel”
<michel.capel@> wrote:

Lance, nice work! I never got to making the graphs, but
yesterday,
while reading the discussion, I thought I might add the graphs.

— In freedomyachts2003@yahoogroups.com, “lance_ryley”
<lance_ryley@> wrote:

I took Mike_c_f35ck’s polar plot excel file and added the
plots
to
them to show them graphically. It’s in files under “f44 40 35
ck
polars with plots.” I didn’t change any of the numbers -
mostly
did
it
to see if Excel could do a polar graph. It can, as long as you
don’t
tell it what you’re doing.

Posted by lance_ryley (lance_ryley@…>)

Michel,
I discovered that I have two staysails and a mizzen spinnaker in my
inventory. I don’t trust the ‘running’ backstays on the vessel
currently, so one of this spring’s jobs is to get a more reliable
system in place. I want to explore the possibilities with the
staysails and spinnaker over the summer to see what works and what
doesn’t. I believe that I even have a sock for the spinnaker. I
appreciate the advice, and I’m sure I’ll have some questions over
the course of the summer.

Lance

— In freedomyachts2003@yahoogroups.com, “michel.capel”
<michel.capel@…> wrote:

Lance, I don’t know if you have any, but staysails are really
helpful on these angles of sail if it’s blowing under 20 kts. I
just
ordered a standard sized all-round (i.e. medium full, for 90* -
150*
apparent wind) gennaker with sock to use as a mizzen staysail.
These
ready made sails are competitively priced and fit fine.

Alternatively, you could try and find a second hand spinnaker and
have the leech shortened with 3 or 4’ to change it into a
gennaker.
That will result in a full headed sail, very good on courses of
120* - 170* apparent wind. As a general rule, you could aim for a
sail with about the same area as your main and mizzen together.

Even your full displacement F40 can be persuaded to fly with one
of
these sails!

Michel

— In freedomyachts2003@yahoogroups.com, “lance_ryley”
<lance_ryley@> wrote:

Thanks - for me, that was really the only point to the exercise -

to

see if I could make Excel plot a polar graph. I already love my
boat
and don’t need the numbers to tell me that. Although they may
come
in handy next year when my wife and I do Marblehead to Halifax -
not
as absolutes, but over a distance race like that, knowing, for
instance, that the fastest point of sail for the Cat Ketch seems
to
be around 120 degrees off true wind angle might help to minimize
the
time between showers.

Bright Star

— In freedomyachts2003@yahoogroups.com, “michel.capel”
<michel.capel@> wrote:

Lance, nice work! I never got to making the graphs, but
yesterday,
while reading the discussion, I thought I might add the
graphs.

— In freedomyachts2003@yahoogroups.com, “lance_ryley”
<lance_ryley@> wrote:

I took Mike_c_f35ck’s polar plot excel file and added the
plots
to
them to show them graphically. It’s in files under “f44 40
35
ck
polars with plots.” I didn’t change any of the numbers -
mostly
did
it
to see if Excel could do a polar graph. It can, as long as
you
don’t
tell it what you’re doing.