How to rig your sail .......................

Posted by Medium Al (hjulbyhavn@…>)

You can improve windward performance by setting your sail differently,
to alleviate the mast getting in the way of the air-flow.

After reading about the G10 rig on this board (see files) and sailing
an old work-boat in Denmark, I changed my F21 to an “in-haul” instead
of an “out-haul” - it works just fine.

here are some pictures of my interpretation:
http://ph.groups.yahoo.com/group/freedomyachts2003/photos/browse/a7c3

Also read the presentation on Samiel’s rig in the document section
called "Sail plan F35 G10 type Rev 01.ppt " there are also pictures in
the pix section.

Spacing the sail away from the mast will cause the air to attempt to
reconnect immediately behind the mast, and spacing the sail will allow
the edge of the sail to fall to the leeward side of the mast and be
exposed to somewhat cleaner air and create a better foil shape as it
lines up better with the mast. These factor are impossible to manage
precisely without serious engineering - however the benefits from
approximating the concept is much better than not trying.

Because I do not have the mast-head hardware to fly the sail away from
the mast at the top I simply increased the spacing incrementally and
fly the mainsail loose footed. It sets beautifully that way because
the F21 boom is plenty long. It is not quite as good as some of my
other trials (loops like Samiel) but it works under all circumstances,
and sail management is absolutely normal.

This will improve light air performance enough that you only have to
worry about flying the Stay-Sail (and not the Jib) in fact you may
prefer to forgo it and ask for a higher handicap rating to make up for it.

The sail area is NOT changed so there should be no impact on you
rating. If anyone complains, explain that you have re-implemented the
spacing the old Cat and Gaf rigs had when using Gaf-Rings.

This is a very interesting mod because it confirms that the old work
boat designs were not just a random response to how to make things work.

A couple of summers ago I sailed a work-boat replica in Denmark with
shallow full keel and “baggy” tanbark linen sails; it tacked to
windward just fine.