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Graphite lashing hooks for kayak hatches #3

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1. The following series illustrates the molding system for the bungee retaining lashing hook seen in picture # 3 on page 1.
A piece of mold release plastic is taped close to the edge of a table with a masking tape. Two long strips of double sided adhesive tape are stuck on along the long ends of the plastic- see the white strips.

3. Create a prepreg of the fabrics you want to use and saturate with epoxy. Here I use about 5 layers of 5oz. twill 2x2 carbon cloth.
4. Smooth out and saturate.
5. Lay down the prepreg between the double sided tapes. The tape strips must not be contaminated with the epoxy.
6. Add the 'mandrel'. It is made from a clear tape covered cedar strip. The strip cross section is slightly tapered so that the tine of the hook points 'downward'. Think of a "U" with the ends pressed together to form a 'tear drop' shape. Peel the protective film. The reason I used two tapes and not just one is because the peel film protects the adhesive surface while the prepreg is positioned onto the mold release plastic. If you are precise, one strip of tape will do. If you get the epoxy onto the sticky tape surface, start over.
7. Fold prepreg over the mandrel so that the two sticky tapes mate.
1. Clamp on a piece of wood so that the mandrel is squeezed 'out' and away from the table edge. Since the plastic mold is held firmly at the table edge and also by the wood, the tapered mandrel wants to slide away from the table edge and from under the pressure of the 2 x 4 wood. This compresses the fabric between the plastic and the mandrel. Clamp it hard and remember that epoxy will be oozing from the sides.
3. Let it harden. Slice through the lay-up on the hook side along the length of the mandrel. Make sure that the clear tape wrap on the mandrel is long enough at the trailing edge so that the folded over lay-up doesn't fuse together all the way around the mandrel!
4. Under normal circumstances, creating a single part mold that would lock the finished component inside due to the taper is a no-no but in our one-off process the mandrel is destroyed and must be removed while the epoxy is still quite elastic the next day or so.
5. Finished blank. Trim the edges and ends of the blank to remove thin sections and imperfections. This piece will yield enough lashing hooks for three kayaks. Again, the hooks have glossy, smooth surfaces on both sides.

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Last page update: 11 January 2020