General cat tips

Catabatics 
All sailboats operate on the same principals. But often we hear people say “cat’s can’t tack and their hard to upright”. Which is not entirely true. Sailing a cat requires a better understanding of what happens to the wind as you accelerate, because cats do a lot of that! The older designs had a hard time turning through the water and slowed tacking to a snails pace. The modern hull shape has cured that! Up righting requires good technique unless your on an ultra light cat such as the Taipan. But these are all easily learned and a cat can teach an old dog new tricks, really.

A modern cat that can’t tack would be due to OPERATOR ERROR. So when you purchase a cat make sure there is someone on hand to show you the tricks of the type.

The great dagger board debate
Due to sailing forces, all sailboats sail with some leeway (side slip) and the more efficient a design is, the less it will side slip. To prevent a boat from slipping sideways a design must employ some form lateral resistance to this force. A dagger board pushed through the hull and into the water is one way of accomplishing this.

However, some folks fear having this appendage dangling below the boat and so designers looked for another way to prevent a boat from side slipping. The low aspect ratio foil (skeg) is one way of doing this. Instead of employing a dagger board the hull itself is used to prevent lateral movement. 

Nacras low aspect ratio keel is an example of this and is employed on the 460, the 500 and the 570. On the recreational designs a moderately deep ‘vee’ shape is used to act as a dagger board. For this to work properly it simply means that more hull has to sit in the water. 

This adds to the wetted surface area and increases the displacement of the boat which in turn slows manoeuvrability. That is not to say that they are slow. Recently we have been using an onboard gps during some of our sails. A Nacra 5.0 in Bali has returned 21.4 knots in good winds which is not to bad and if you were a keelboat sailor you would be over the moon at that speed, but!

A dagger boarded design by comparison can have a hull that has less wetted surface area as the dagger board will take all the lateral loads of the platform. 

A more rounded cross section offers a minimum wetted area which increases the potential speed of the craft. More importantly, the rocker of the hull can be increased leaving the bow and stern areas ‘raised’ out of the water. The pivot point for the hull then becomes the dagger board itself with the ends of the hull being free to ‘slide’ over the waters surface during tacks and jibes. 

What this all means is that a cat with dagger boards will go upwind at an angle closer to the wind, it will tack and gybe easier and it will probably be faster through the water than a comparable dagger board-less design.

All in all, a better sort of cat.

Maintenance
Cat platforms are generally pretty tough so with just a little care you can keep them in top shape. In our harsh tropical environment and being so close to the equator, the worst element is the sun. Keep everything out of the sun as much as possible.

Cover it
The worst thing you can do is leave your equipment exposed to the UV rays. From experience gained over the last 20 years, Sunbrella Covers last 10 years (S$ 800 approx.) Acrylic covers about 5 years (S$ 500 approx.) and cheap PVC just 18 months (S$ 400 approx.). A quick glance will tell you that the Sunbrella one is cheaper for the long run. But the real advantage of Sunbrella type materials is that it breaths in the high humidity – your boat will be a lot better off. The Acrylic and PVC types, on top of being environmentally UN-friendly, trap moisture inside – anything you leave moist on the deck will turn into mould in no time at all.

Wash it
Strange as it sounds but a good wash saves its skin! Make sure you get the salt off fittings and out of the fabrics. 

Roll them
Sails like to be rolled and not folded. The more you fold them, the quicker they’ll become rags. Woven sails like Dacron ones roll fairly easily. The mainsail can be rolled easily by folding the sail over at the No. 2 batten (from top) and rolling from there. This helps keep the battens parallel to one another. 

Laminated sails like Kevlar/Mylar etc…Do not fold ever! Preferably, roll as the sail comes down. Kevlar doesn’t like sun so don’t put your sails unless you’re sure you ready to go on the water.

In either case, the best and quickest way to destroy sails is put them up and leave them flap in the breeze. Don’t do it. Put a little sheet pressure on, just enough to take out the flogging.

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