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AOC & Hawkeye Manufacturing Innovate Spa Production

  • Tuesday, 5th March 2013
  • Reading time: about 3 minutes

AOC and spa producer Hawkeye Manufacturing have collaborated to produce one of the largest, single-piece spa liners on the market.

The Bossetti combination spa and hot tub from Barefoot Fitness Spas is a 2,000-gallon tub with seating for up to five adults. Features include 37 stainless-steel spa jets, six adjustable-flow swim jets, flow fountains and a waterfall.

AOC explains that Hawkeye’s workforce uses its materials technology and technical support to ensure the quality and durability of this product. “With a unit this large, we had to be right the first time,” declared Casey Murray, Vice President for Hawkeye Manufacturing. “The unit’s size makes it difficult—and more expensive—to transport and install. Any issues in the field would create an enormous cost.”

AOC says that Hawkeye start with a sheet of acrylic that is heated and vacuum-formed into the shape of the spa’s smooth, seamless uni-liner. After mastering the technique for forming the large, complex Bossetti liner, the next challenge was developing a protocol for the fibre-reinforced polymer (FRP) structural composite back-up.

According to Murray, the major concerns for the composite manufacturing step were:

  • Precisely controlling the composite thickness variations that are needed for the complex liner,
  • Controlling the exothermic heat generated during composite cure to prevent temperature spikes that could distort the liner shape, and
  • Ensuring an extremely strong adhesion between the composite and liner.

Murray said Hawkeye Manufacturing found the right solutions with help from AOC Sales Representative, Berk Pleasants. “Berk has been our ‘go-to’ person for composites technology for about twenty years. We ran AOC’s recommendations by the acrylic supplier and received confirmation that the composite and acrylic liner were compatible.”

The first step for the back-up composite is the application of a skin coat consisting of chopped glass fibres and high performance Altek H100 vinyl ester. According to AOC, this technique is similar to that used in boat building and serves the same purpose, to prevent moisture from reaching and affecting the integrity of the thicker composite structure. The vinyl ester also provides excellent adhesion between the composite and acrylic. To finish the back-up laminate, Hawkeye technicians apply chopped fibre in Altek C949 polyester.

“This spa is larger than anything we have ever produced before,” Murray stated. “The consistency of AOC resins and outstanding AOC technical support were essential to helping us reach this milestone.”

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