How a Hallberg-Rassy hull is built

At Hallberg-Rassy Marinplast AB, an affiliated company owned by Hallberg-Rassy AB, all Hallberg-Rassy hulls are made. No other hulls are built here. The plant is located in Kungshamn, about one hour drive north of the yard. We will here follow how a hull is laid up.

This is what the mould to a hull looks like. The outside is reinforced with strong metal stringers. The inside has a high glossy finish. The mould is made in two parts, which allows us to build the hulls with an integrated rubbing strake on the hull and a deep bilge. This would not be possible if the mould was built in one part.

The hull is laid up from the outside and in. We start to mask the part of the hull that will be blue. The inside of the mould is black. This makes it easier to see where you have put on white gelcoat.

The gelcoat is based on isophtalic resin. The isophtalic resin is very resistant to water penetration and kkeps its glossy finish very well. The white gelcoat is sprayed on. White for the hull and blue gelcoat for the Hallberg-Rassy stripe. A vinylester based barrier coat is applied. This makes the laminate more resistant to water penetration, and at the same time it protects against print through, which is if the glass fibre is visible in the surface finish.

Compared to the single skin hulls in the old days, today's hulls are insulated, which means a superior torsional stiffness of the hull.

The material used is a PVC foam called Divinycell. It is fitted when the laminate is still wet, and then covered by laminate. The Divinycell is a superior material for a cruising boat, compared to balsa. The PVC foam has closed cells, which means that the material does not absorb water. The Divinycell will finally be covered with more laminate.

The stern with the integrated bathing platform is made separately.

The parts of the hull are laminated together before the mould is opened. The points where the parts are put together are laminated so carefully that this will be the strongest part of the hull.

The decks are built in the same way as the hulls. Divinycell used as a core material and strong backing plates that are laminated into the deck under deck hardware.

All laminate is carefully rolled out by hand. Temperature and humidity is strictly controlled during the process and registered together with batch numbers, start and stop times, employee numbers and so on in a log book.

The grid system is an advanced design that reinforces the hull under the waterline. The grid distributes loads from the bottom out in the hull in case of grounding. There is a steel beam moulded athwartship under the mast support to carry the strong loads. The grid will also be the support for the floorboards.

The rudderpost is made of solid stainless steel.

The shaft is laminated into the rudder, forming one solid, very strong unit.

The grid is bonded into the hull.

A metal frame is used when the bulkheads are laminated to the hull.

All bulkheads are laminated from both sides, which gives additional strength.

Deck and hull are laminated together. This is made from the inside. This gives a superior torsial stiffness and cannot leak. The coaming between hull and deck is covered by a beautiful teak toetrail. On centre cockpit boats,  the rods for the stanchions will be fitted into the solid coaming. The bulkheads are laminated to the deck from both sides. The inside of the hull is painted twice with topcoat.

The hull is now ready for transport to the yard in Ellös. All hulls are trucked to the yard. All equipment like tanks, engine and joinery will come down through the companion hatch. Everything that goes down in the boat can go out without having to take the boat apart. 
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