Placing the foam sheets

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Here we see the foam laid out on the table with the template on top for marking the foam for cutting. The individual foam pieces are held together with a building product, sometimes called “Gang Plates”. These are steel plates, about 2 inches wide and 4 inches long with lots of sharpened legs formed through them and you drive them into the foam at the junction points to hold the individual panels together. Available at any building store. You do not have to worry about any holes the legs make in the foam as they will be filled with resin during the infusion. Another good idea is to make wiggly lines between each junction so that when you reassemble the panel, all the individual pieces go together in the right places.

The material being used for this project is Divinycell PVC foam, 5/8 inch thick, 80 pound density, cross cut on one side and drilled through. The cross scoring and through drilling helps the resin travel over the foam and through to the other side during the resin infusion process. A good information site with specifications and uses is http://www.diabgroup.com/europe/products/e_prods_2.html This is one manufacturer of foam products. There are others.

A closer look at the “Gang Plates”.

Steve is marking the foam with a line that shows the lower extent of the glass on the inside of the panel. The lower portion of the panel will be formed and therefore does not require glass at this time. This is the first time we see the use of the full length batten. This batten is used to mark fair lines on the panel.

For the foam to fit flat on the glass and the table, we have to cut the rebates into one side of the foam, for the bow and the stern.

All we have to do now is remove the “Gang Plates” and we are ready to put down the inner glass layers. The single line on the panel is the lower limit of glass for the inside of the panel.

Just before we install the upper layers of glass, you can see that the top of the foam close to the deck edge radius former is chamfered. This is to help the glass make a fair transition from the surface of the foam , down into and around the deck edge radius former. Glass does not like abrupt changes and the chamfer helps a lot.