We have now achieved a huge milestone towards completing our boat. It is now airtight.

Today we attached the last of the cabin windows. The cockpit windows and door have been fitted for a while, but we had to wait until the non-skid deck paint was completed before the fixed windows on the cabin sides could be fitted.

The design specification for the windows had an option of either 10mm acrylic (perspex) or 6mm polycarbonate (lexan). The acrylic has a harder surface and is less prone to scratching, but the polycarbonate is much stronger so can be used in thinner lighter panels. Three sheets are required for the windows around the outside of the cabins, and a fourth required for the opening cockpit windows. We used one sheet of the 10mm acrylic for the opening windows on the turret front, as these will be handled and the scratch resistance will be a benefit. On the sides of the turret and the lower cabins, we used the 6mm polycarbonate, and for the opening windows inside the cockpit used 6mm acrylic.

Peter Snell, the designer, provided detailed instructions for the fitting of the windows. Those instructions were excellent, allowing us to complete a very messy job with no extra effort for cleanup. Because the job was so messy, there are no photos of the process. Both surfaces (the plastic sheet and the cabin side) had to be coated in a nice smooth bed of silicon. Silicon is used for this instead of the Sikaflex product used on the hard deckware, as the windows will need to be removed one day to replace any crazing or scratches. We applied the silicon out of the gun and smoothed it into concentric rings around the rim of the window. But by following the instructions and utilising the protective film on the sheets of plastic, we were able to clean up the excess silicon with no mess.

Point your mouse to each of the small photos below, and you will see the process of removing the protective film from the inside once the silicon had half set.

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