The new Mattia 60 costs around €1.5 million to buy.
The new Mattia 60 costs around €1.5 million to buy.
Using the vacuum bagging infusion process reduced labour costs by over 25%.
Using the vacuum bagging infusion process reduced labour costs by over 25%.

The Mattia 60 is 19 m (62 ft) long, 9 m (30 ft) wide, with a 23 m high mast, and is capable of sailing at up to 23 knots.

Following extensive investigations into composite materials and processing options, Mattia selected vacuum infusion for the composite hull and deck, high performance SAN foam core material, plus a structural adhesive to bond the hull bulkheads and to fix the deck to the hull. This combination resulted in the weight of the catamaran being reduced by 2000 kg. 

Laminate design

At the design and construction phase, Mattia took advice from its suppliers about the latest composite process technologies available. Resintex Technology, which specialises in closed mould technology and supplying composite raw materials and ancillaries to the Italian marine market, and Richmond Aerovac, Italy, recommended vacuum bagging as the optimum infusion process to consistently and cost effectivively produce high performance large composite parts such as the 19 m long hull and deck.

To provide a high quality, marine approved laminate construction for the hull and deck Crystic VE679-03PA, a low shrink, long gel time infusion grade resin, was specified, in combination with Crystic VE679PA skincoat behind a marine-grade ISO/NPG gel-coat. The resin and skincoat are both DCPD modified vinyl ester resins developed by Scott Bader. These resins are also said to provide an improved aesthetic finish due to lower print through.

In areas of the superstructure subject to high stresses and loads, such as the slamming area of the hull, sandwich laminate sections using Corecell™ M foam core material from SP-High Modulus were specified. Corecell M-Foam is reported to provide a combination of high shear strength with low density, high elongation, high temperature resistance and low resin uptake.

Infusion process

By using a vacuum bagging process, Simonplast and Elvideo Giovanetti, the two Italian shipyards which produced the hulls and the decks for the Mattia 60, were able to make significant improvements compared with their traditional hand lay-up open moulding process. Infused parts were significantly lighter as less resin was used and more evenly distributed through the laminate. Tests proved that higher mechanical properties were achieved in the infused laminate and parts were able to be produced with a much greater consistency.

For such a large and complex vacuum bagging set up, when the infusion process is started it is essential that the resin has a predictable, controllable and reliable long gel time whatever the time of year. We trust Crystic VE 679-03PA pre-accelerated resin to perform as stated in the technical data sheet. We have been able to consistently produce high quality vacuum infused hulls with an excellent laminate finish.
Simone Piscitelli, Production Director, Simonplast

Manufacturing by infusion also resulted in reducing overall labour costs by over 25% and, compared to open moulding, emissions of styrene volatile organic compounds (VOCs) were reduced by over 70% in both shipyards when they switched to vacuum bagging.

Structural adhesive

To further reduce the overall weight of the catamaran, Mattia approved the use of Scott Bader’s Crystic Crestomer 1152PA structural adhesive, which has Lloyds, DNV and RINA approvals for composite marine bonding applications.

By bonding in bulkheads instead of over laminating significant reductions in the weight of the hull were achieved, and the overall mechanical performance of the hull construction was improved.

A reduction in production time was also achieved by bonding instead of over laminating.