From a “cruiser” to a racer

Evolution of a Corsair Marine F28 CCR

The Corsair Marine F28 CCR is already a racer!! What I am trying to do is just to give her a more aggressive look, save some weight and set her up for blue water sailing

Piercing bow

I have decided to modify the bows of the amas, to give to the trimaran a much modern and aggressive look. I took inspiration to some of the newest design around, seem piercing wave is the way to go.

First sketch

Preparing the shape and foam to be glued to the bows. I will not modify the original hull so that it will be reversible to the original shape if necessary.

Gluing and aligning the bows to the amas

Foam gluing with vacuum and preparation for sanding stages. Lines are set to have a rough reference for the sanding process, they are tangent to the hull and ending up at the nose.

Fine sanding, after it will be possible to start the laminating procedure.

First step laminating

High aspect radio rudder

Building the new full carbon high aspect ratio rudder.

Back bone

Covering the back bone with high density foam

Sanding down the rudder shape

Starting with lamination

Carbon rudder case. I will not modify the existing one for two reason: it is too heavy, secondly I want to keep it as it is in case I need to go back to the original rudder.

On boat test

New carbon tiller

Rudder case and tiller match up

Filler and finishing coat

Improving the rudder gudgeon, for a much more precise feeling.

Carbon tiller extension

The tiller of an F28 is not the most comfortable thing, after several design concept i have decided to build an extension tiller that allows me to steer the boat in a more comfortable position when sited in the cockpit and closer to the sail maneuvers.

Rotating mast carbon leverage

I was sailing across the Med and the bolt of one side of the original system got lose and fell out. With the mast up it is impossible to be fixed. Since that episode I have decided to change the solution. Nevertheless the design is not so racing oriented of the original leverage. Plus I have rigged the leverage so that you can control better the angle and avoid any kind of movement in wavy condition. The new leverage stay much closer to the deck, possibility that the lines get couth in the leverage are much lower.

Carbon Boom

The original rotating boom was not that bad, but I found it quiet difficult to roll the sail without wrinkles, and reefing was a nightmare for the sail. Since I am planning to put new sails on the boat and sailing often reefed, I have decided to go with a standard boom and lazy bag layout in order to increase sail lifetime and have a more reliable reefing system. Maybe also save some weight.

Carbon spray hood

On the last sail trip that I made in the Mediterranean I faced some rough seas and strong winds. I was not happy with the original cockpit entrance. It is impossible to go below deck without flooding the cockpit. This force me to come up with a new solution. Taking inspiration by ocean racing sailing tris, I have designed a raised deck that allows me to enter from a door that can also be sealed closed, it also allows me to stand below deck and gives me a clear view forward. Nevertheless gives me some spray protection when steering.

Design and cardboard proto. I have imported the drawings of the Corsair manual and scaled them to 1:1. From there I have build up the base model.

For some might not look so cool, for me was awesome. Did not have much to think, started right a way with the mold production.

The production having the 3D model was not so complicated, the foam it is easy to work and to get in proper shape. The mold must be fully sealed in order to pull a proper vacuum during carbon lamination. I have used unidirectional plus twill carbon layers.

After the first carbon layers I have added 20mm of foam to increase stiffness without increasing weight. Smoothed the foam, this is a special foam (Airex C70) compare to the cheap one of the mold. The compression module is much higher.

Had some wrinkles here and there but not that disturbing. Lets go and installed on the boat.

Fits!! Time to cut up the boat…

Perfect. I have glued the over structure to the deck just to keep it in position. I will than bond it to the deck with carbon fiber.

Just need a door…

Now that everything is glued, can laminate all together. Quiet a time consuming operation specially if you want to pull vacuum. At the end it will be very similar to a monocoque construction.

Time to put some filler, sand, and finally paint.

Last detail eagle eye windows

Some painting on the door to match the base color of the boat.

Converting wooden parts to carbon fiber

I have started from the simpler parts. I’ve toked all the wooden parts inside the boat and converted them to carbon fiber sandwich parts. Tables, covers, panels, etcetera…for this few parts I would expect an overall weight lost of 6-7 Kg