Cored glass/PU speakers, tabletops impress
Sandwich panels provide music, sound masking sans weight.
Using patented technology and a wide range of finishes, SD4 Technologies (Muskegon Heights, MI, US) is turning its lightweight Dakore laminated panels into speakers and creative solutions
for acoustic and furnishing challenges in restaurants, office buildings, RVs, boats and trade show displays. SD4’s panels feature a sandwich construction of paper honeycomb core wrapped in fiberglass, then sprayed with Baypreg polyurethane supplied by Covestro LLC (Pittsburgh, PA, US). This not only provides good flexural and torsional stiffness and resistance to deflection, but also cuts weight by 50% vs. conventional laminated panels.
“We’re using a proprietary mix of the Baypreg products to get the specific performance we need,” explains SD4 president David Miller. Used in composite automotive load floors for years, Baypreg two-part polyurethane offers, in addition to low weight, good mechanical properties and an efficient, low-VOC emission, short-cycle manufacturing process.
SD4 has found a receptive market in western Michigan’s extensive office furniture industry. “Traditional materials for tabletops and architectural panels are heavy,” says Miller. This requires more manpower for installation and also increases shipping costs. Particle board, a common alternative, lacks the strength-to-weight ratio needed for many applications. In one case, SD4’s customer was able to build a 4 ft by 8 ft by 2 inch (1.2m by 2.4m by 51 mm) library table, with a 75-kg weight reduction, using Dakore panels in the top instead of particle board. Miller says SD4 also has made 0.6m by 1.2m panels that look like marble and granite, “but weigh only 9 kg. We actually suspended these from the ceiling of a restaurant as a demonstration and, with our speaker technology, were able to fill a whole dining room with music.” Surface finishes also include laminates, wood veneer, concrete, dry erase/marker board and stone veneer, and a variety of edge effects.
Miller explains that SD4 now receives many inquiries from architects, thanks to the growing trend for noise cancellation and white-noise/sound-masking systems aimed at improving privacy and productivity in the workplace and enhancing customers’ experience in bars and restaurants.
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