We have started building our first fiberglass Wharram. James and Haneke had a set of molds built based on their very popular Tiki 26. They built one boat and for various reasons the project fizzled. Earlier this year we had the molds shipped to us here in Jupiter from England. The molds were in pretty good shape but we spent many hours fairing to improve the quality of the finished parts. Below is one half of a hull mold. The hull is laid up in two halves and then taped together down the center line. After waxing and waxing and then a little more waxing we spayed red gelcoat onto the surface of the mold. After this tacks off we applied a layer of 3/4 oz chopped strand mat (csm). This bonds well to the gel coat and helps prevent print through form the structural laminates. Earlier this year a fellow named Bill Holmes joined our team as a carpenter. Less then two months later we signed a contract for these two FRP boats. "Holmsey" has worked for several large fiberglass sail boat builders in the past and brings a wealth of experience and expertise to our program. It's funny how things work out sometimes.
After the mat sets up we apply a layer of 1708 fiberglass. This is a layer of csm backing two layers of unidirectional fibers oriented at +/- 45' to the length of the fabric. This biaxial fabric is much stiffer for a given weight than woven cloth.
These outer layers of fiber are applied using vinylester resin which provides protection from osmotic blisters. After the 1708 skin sets we then vacuum bag a layer of 3/8" Divnycell foam into the hull half.
The picture below is after the bag came off with some of the pvc bleeder manifolds still visible. You can also see where the vacuum has pulled resin through the perforations in the foam. These holes are to ensure that no air becomes trapped between the foam and the laminate. The craftsman in the photo is Bill Holmes.
After the foam another layer of 3/4 oz mat and another layer of 1708 complete this hull half.
Once the two hull halves are ready the molds are bolted together along the center line flanges. There are locating dimples that key the two halves into precise orientation.
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