Thursday, April 2, 2015

Genoa inhauler

We have just brought Nimrod south from Townsville to the Whitsundays, where she will live for the next seven months.

Plenty jobs; boats don't like to be unused. We last saw her at the end of October.

One mission which might interest other Seawind owners is the fitting of a new genoa.

We have already a small self-tacking jib, and a larger light genoa. The former is a bit small, and the latter a bit big. In addition the sheets for the genoa run outside the cabin, which limits how high you can point into the wind. With the self-tacking jib, the autopilot set at 30° works. With the genoa the figure is more like 40°.

We have developed a technique called 'inhauling' for improving the pointing with the genoa. I originally tried to do it with ropes and pulleys from the boom, but it was all a bit flimsy. Recently we have worked out that we can use the sheets from the self-tacking jib, when centred on its track, to 'inhaul' the genoa sheets to produce a finer tacking angle. It works pretty well, although the large light genoa hits the spreaders when you do it without also reefing a bit.

So we ordered a 'Number 2' genoa from Neil Tasker at Barracouta Sails, and it arrived just before we flew to Townsville.

Step 1. Centre the jib sheet car on its track using the movable stops.


Step 2. Attach the self-tacking jib sheet to the genoa clew, as well as the genoa sheets.


Tension the self-tacking sheets to pull the clew inboard. Once you have it right, you can leave this alone when you tack.


This is the angle without 'inhauling'.


This is the angle with inhauling.


Two reef points along the foot.

Large light genoa.        38.2 m².       10-15,000 denier.    (High load areas 15,000, spaces 10,000) 
Recommended wind strength limit 20 knots.                  Boat points 40°
Number 2 genoa.          31 m².          20,000 denier.        Boat points 35° with inhauler.
Self-tacking jib.            22 m².          25,000 denier.        Boat points 30°

The plan is to leave this Number 2 genoa on most of the time and use it as follows in different wind strengths.

< 20 knots: full genoa.
20 - 25 knots: one reef.
25 - 30 knots: second reef. 
> 30 knots: storm jib wrapping round the fully furled genoa.

As the genoa is gradually furled, and the clew moves forward, control comes increasingly from the self-tacking jib sheets rather than the genoa sheets. 

Comments welcome.

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