Epoxy building technique


Epoxy is used in the race boat industry, the America's cup and the Volvo ocean race. Epoxy is the standard for luxury Sailing Yachts as the Baltic and Wally Yachts. This Epoxy Boat construction is also used by Hanse Yachts.Hanse Yachts is one of a few production boat builders who have implemented the use of Epoxy resin into their new e line: Hanse 470 and Hanse 540 and Hanse 630. In the past, Epoxy resins have only been selected for semi-production and race boats, where reduced weight and laminate quality are key factors. Changes in boat style, onboard equipment and expectations of boat owners means that Epoxy resins are becoming necessary to offer a boat that performs well on the water. Hanse Yachts: Advantages of Epoxy  - Better adhesive properties (the ability to bond to the reinforcement or core) - Longer working time, reducing building phase and secondary bonding - Superior mechanical properties (particularly Strength and Stiffness) from material itself and through process ability (vacuum bagging, optimum strength to weight ratio) - Improved resistance to fatigue and micro cracking - Reduced degradation from water ingress :Hanse Yachts: Advantages of Epoxy - Weight and Strength  - Reduced hull weight compared to Polyester through increased strength and stiffness of Epoxy laminates (at design stage). - Use of alternative construction method, only possible because of certain working properties of Epoxy (like vacuum bagging techniques) leading to: - Controlled (and increased) fibre volume fraction to optimise strength to weight ratio: strength/modulus are fibre dominated properties, therefore more fibre, better properties. - As a guideline, a 45-50 foot boat built in Epoxy can weight up to 1000kg less than it's equivalent polyester version. Hanse Yachts: Improved Construction method  - As a part of the construction method, Hanse Yachts have chosen to "Vacuum bag" the Epoxy boats. This process reduces any potential excess resin and removes air entrapment, which improves weight and add strength to the hulls. :Hanse Yachts : Advantages of Epoxy - Water Penetration and Osmosis - Both Polyester and Vinylester resins are prone to water degradation and osmosis due to their molecular structures. - As a result, a thin polyester laminate can be expect to retain only 65% of its Interlaminar Shear Strength after immersion over a period of a year (or saturation), compared to 90% for an Epoxy laminate. - Due to the building method chosen by Hanse Yacht, the effect of osmosis is completely removed, but limited to the outer surface of the boat. There is no possibility of osmosis on the structure. - To delay the onset of osmosis, it is still necessary and recommended to use Epoxy resin primers before the application of antifouling. Advantages of Epoxy - Fatigue and Micro Cracking - Epoxy resins are superior at withstanding cyclic loads and therefore Epoxy boat hulls stay stiffer for longer. - When boats are highly loaded, e.g bumped into the dock or from high rig loads, micro cracking failure can occur within the laminate. Epoxy resin resistance to micro cracking is much higher than Polyester. - The resale value of a boat whose structure is unaffected by osmosis and whose fatigue properties are better is likely to remain higher; the boat will remain "stiffer" for longer. Other advantage of Epoxy - Odour - As Epoxy resin do not contain any solvent, there are virtually odour free once cured. - The interior of boats build using Epoxy don't have the typical "styrene smell", as all polyester production boat have.

Strength after 1 year Epoxy vs. Polyester

  • Epoxy 90%

  • Polyester 65%

Bonding strength Epoxy vs Vinylester

  • Epoxy PSI 100%

  • Vinylester PSI 25%

SP systems epoxy vaccum process