Seawind 1160 Deluxe, Owner'S Manual

Page: 19 / 65

Owners Handbook 19
S e a w i n d C a t a m a r a n s
the third by snatch blocks. Each reef takes in around 20% of the sail area. The
third reefing point meets AYF Cat1 ½ luff storm sail requirements.
The standing rigging consists of forestay and side stays of 10mm 316-grade 1x19
dieform wire. The diamonds are 8mm 316 grade 1x19 wire. All are terminated
with open body rigging screws.
All halyards, reefing lines and sheets lead through turning blocks and organizers
to clutches, cleats and winches in the cockpit. The self tacking headsail on
curved traveller track sheet and tack control is also in the cockpit.
The Jib may be controlled or put away with the headsail furler control in the
cockpit. The headsail has Sunlight UV Protection in its fully furled position. The
mainsail is also protected from Sunlight UV while zipped in the lazy jack and
main sail catcher system.
Rig Tension
When your boat was first launched the mast was stepped and the rig set to the
correct tension. During the first month or so of sailing the wire rigging will
stretch a small amount. This is quite normal and any slack can be taken out by
taking up the rig tension. After this initial “bedding down” period, the rigging
wires should not change too much and examination on a six monthly basis should
be sufficient.
The spreader diamonds control the mast pre-bend and ensure that it cannot
bend sideways. The mast is initially set up with approximately 75mm of pre-
bend, that is, the mast has a gentle bend along its length so that at the
midpoint it is approximately 75mm from an imaginary straight line between
each end of the mast. This is achieved by first tensioning the outer diamonds.
With the correct pre-bend achieved, continue to adjust the spreader wires to
get the mast straight in a sideways plane. Second, take up the inner diamonds
equally until they are firm and sharing the load. For advanced tuning this pre-
bend should match the cut of the mainsail.
Having set pre-bend you now need to look at the stay tension. The forestay
length has been determined to allow the top of mast to have an aft rake of
approximately 15ins (400mm). This rake affects the overall balance of centres
of effort for the boat. Take up the outer side stays on both sides evenly,
changing each side a few turns at a time. Do not over tension; take them up
evenly until the stays feel firm.
Last, take up the lower stays evenly until they are firm against the pre-bend
provided by the spreader diamonds. Their purpose is to contribute to holding
the mast in column with the pre-bend and stop it from “pumping”.