Male Mold Plug and Composite Shell Construction Techniques
By David M. Sianez Ph.D.
After many years of pursuing techniques for male mold plug creation and composite shell construction, I’ve developed a method that is inexpensive and fast. It calls for sheets of rigid foam insulation stacked and screwed in multiple layers to achieve the desired mold shape, then covered with multiple layers of carbon fiber and Kevlar cloth. WEST SYSTEM® Epoxy is used to bond the composite structure and cured at room temperature.
Composite shell construction became a pursuit for me following a visit to the Smithsonian National Museum of American History. While walking through the exhibits I came across a human-powered speed vehicle called The Gold Rush. It had been ridden by cyclist Fast Freddie Markham, the first person to exceed 60 mph on a faired bicycle. Going that fast under human power alone was an idea that challenged me, and later became my passion. Continue reading →
A couple of years ago my son Ian asked me about building an A Class catamaran. Having built several of these in the past and knowing what was now on the market, I came up with a build method that would:
Allow us to build a competitive design.
Be at or under the class minimum weight of 165 lb.
Be as strong and stiff as anything on the market.
Be competitive in quality and price, but not get trapped in exotic equipment expense. This meant no vacuum bag, no pre-preg, no resin infusion, and no autoclave.
Above: Jeff Wright, Vice President of GBI Technical Services, poised to take a deep dive into types, materials, costs, weight, and stiffness of flat panels.
Many WEST SYSTEM® customers appreciate the benefits of cored composite construction. They understand that it creates a part that is lightweight, strong, and stiff. We often receive calls from these customers inquiring about using a composite panel when building or repairing something that would normally be made of plywood. Such projects may include a new center console for a fishing boat or the replacement of flying bridge side shields. Determining the best material requires consideration of many aspects of the project, but often comes down to cost versus weight. Continue reading →
Above: Bonding fasteners in high-density urethane (HDU) foam calls for drilling an oversized hole slightly shallower than the fastener length and setting the fastener in an annulus of thickened epoxy.
Many of our readers who are familiar with WEST SYSTEM® Epoxy products for building and repair already know the benefits of fastener bonding techniques. WEST SYSTEM Epoxy has been used in other industries for many years as well, and these folks apply knowledge and techniques developed in the marine and aerospace industries in their work. A good example is the sign industry, a huge industry in the U.S. with companies ranging from mom & pop garage operations to multimillion-dollar corporations. Continue reading →