Summer Catamaran Project

PART 1: The Bows (2023)

PART 2: The Hulls (2024)

View 2024 (NEW)

PART 3: The Sterns (2025)

[COMING NEXT YEAR]

Our catamaran, Anticipation, in the Bahamas, 2013

Introduction: This summer of 2023, my father and I decided to extend the bows on our 2004 35’ Wildcat 350 catamaran. Her name is Anticipation, which is the perfect name according to me, because she is a very slow vessel. And we managed to figure out why; her hulls were too wide when we compared them to other similar catamarans.

Her bows were also quite flat at the tips and didn’t cut through water very well, which could be concluded visibly when cruising.

Also, her crossbeams lay very close to the surface of the water, and any wave with an amplitude greater than two feet would violently impact the bottom.

Our goal: Increase the displacement to lift her higher out of the water and prolong the hull to make her more hydrodynamic in regards to her hull width.

Our long-term plan is to increase her length by about 20%: 3 foot extensions at the front and, later on, 3 foot extensions at the stern. Then, upgrade the engines to make up for the increased weight, length, and displacement.

Methodology: Since my father is a chemist, he took the role of material researcher. He found and bought the materials needed for the project. I took the role of engineer and designer, figuring out how to make it structurally integral and, most importantly, function correctly. I also designed the shape to improve the look of our catamaran.

PART ONE: The Bows (2023)

Original bows - before any work began.

Week 1:

We arrived and had to set up the boat to live on it for 6 weeks.

The materials for the extensions were accumulated during this week.

A very early template was designed.

Template created from insulation foam.

Original bows without gelcoat - port bow has the insulation foam template.

Week 2:

This week was spent grinding off the original gelcoat so we could attach the bows directly to the boat’s fiberglass structure.

Repairing of wet rotting balsa core found.

Creating the bow extension structural frame from divinycell foam according to a the insulation template, and then fiberglassing it.

Placing the structural frames into the bows to make minor adjustments.

Structural frames placed onto bows #1.

Structural frames placed onto bows #2.

Bow extension structural frame from divinycell foam.

Extensions with floatation foam and strap.

Week 3:

Pouring expansive flotation foam into the volumes.

Gluing the extensions onto the original bows. We used a strap to hold it in place firmly for 24 hours and used polyester glue to ensure its structural integrity.

Then the bottom sections were glued on, in the form of a V-shape to provide better durability and more volume.

Cut and shaped floatation foam for the next step.

Structural frames placed onto bows.

Bottom section forming a V-shape.

Cut and shaped floatation foam.

Single sided fiberglass panels attached.

Bow extension after the final shaping.

Bottom and top with flexible foam attached.

Week 4:

Once we had the basic shape of the bows, single sided fiberglassed foam panels were glued on.

Flexible foam panels were glued on to the bottom and the top areas, which needed rounded surfaces.

When all panels were on, the final shaping process began. This included a lot of sanding and fairing, using marine Bondo.

Port bow extension finalized after fairing and sanding.

My brother, my father, and I fiberglassing the port extension.

Week 5:

To apply the final fiberglass, the surface must be perfectly flat. Fairing and sanding was done extensively to achieve this.

This week, my family arrived and stayed with us until the end. They helped with fiberglassing, as two people are not enough.

One bow extension was faired, sanded, and fiberglassed, with 4 layers on the sides and top, and 8 layers on the bottom.

Application of the first layer of gelcoat on the port side.

Application of first layer of gelcoat on the starboard side.

Week 6:

The second bow extension was faired and sanded for the fiberglassing.

Then it was fiberglassed the same as the first extension, with 4 layers on the sides and top, and 8 layers on the bottom.

During this, the first extension’s fiberglassing was faired and sanded to perfect the surface.

Once both bows were done with the final fairing and sanding of the fiberglass, the gelcoat was applied with a total of 3 layers.

We finished eight hours before our flight back home to Europe.

Part 1 - Final Product (2023):

Note: This is the "final" product from our side. However, there must be one final layer of gelcoat applied professionally for a perfectly smooth surface, which is planned for the following summer.

Issues during the project: There were two live wasp nests living inside the mast that we had to deal with for the first two weeks. In early stages, the starboard extension had to be taken down and re-glued on, because it moved during drying. The last pieces of fiberglass cloth were defective and I had to spend hours grinding it off once it had consequently dried improperly with air bubbles. The last layer of gelcoat on the starboard extension had to be dried using an AC unit exhaust, because the outside air temperature was too cold.

The method I used to get the both extensions as similar to each other as possible was: engineering the port side first, and then mirroring all the individual pieces to make a mirrored version for the starboard side. However, I forgot to take into account that both original bows were different. This lead to hours of making many minor changes to the mirrored extension to make it fit into the original bow properly.

Also, it is possible to see that the entire starboard extension is crooked, tilted slightly inward. This is not a mistake made by us, but a mistake in the original boat mold. The entire starboard hull is crooked, which I noticed is a feature all Wildcat 350s have. We therefore had to tilt the starboard extension inward to have it fit and function correctly.

Side-by-side Comparison

PART TWO: The Hulls (2024)

The keel with ground-off barrier coat and paint.

Ground-off rub rail where rotten balsa core was found and removed.

Week 1:

Anticipation's hulls are full of moisture. A moisture meter maxes out almost anywhere you put it on the hull under the waterline. This is normal for Wildcat 350s due to their notorious build quality stemming from cost cutting and laziness.

Water would leak through the rub rails on the sides as well, so we planned on removing those completely.

We drilled holes to look for and replace rotten balsa core, only finding two bad areas.

The extremely long keels and small rudders also deeply limit the boat’s maneuverability. So, we set out to redesign both keels and rudders.

This week comprised of days and days of grinding.

Mildly rotten balsa wood core we found by drilling a hole.

Partially ground-off rudder.

Cutting the keel.

Week 2:

I cut off around a meter off the back of the keels, planning to add that surface area back on by extending their depth.

We would extend the rudders by both extending their depth and length.

Both of these added features will increase the boat’s maneuverability.

Original shape of the rudders with an inch cut off from the back and underside.

Glued on Airex PXC Fiberglass Reinforced Foam core keel additions.

Week 3:

This was the week of gluing, sanding, grinding, and fiberglassing. We glued on the keel additions and rudder additions. We decided to use fiberglass reinforced Airex PXC foam as I needed extremely strong material which could hold both the entire 11 tonnes of weight of the boat (on land) and withstand the forces acting on the rudder.

Since we added to the side cross-sectional area of the boat, I had to take into account the extra force acting against the boat from the wind. Therefore, when transforming the keels, I decided to increase the original area by 10% to help counteract that additional force.