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These two sheets of foam were hand-formed (not in a mold); see Turtledeck for details on hand-forming. A center section of black HD80 and blue LD60 will connect these two sheets together.
A separately formed section under the windshield is needed. This section is raised to force air coming under the leading edge of the windshield upwards to help clear fog off the windshield’s inner surface. It is also high enough that the rider's breath goes below it to prevent fogging the inside surface of the windshield on cold wet night riding. And it blocks sun from heating the rider. With an open cockpit, that’s a difficult challenge. But that open cockpit has saved my butt a couple of times because I can easily hear oncoming traffic.
The disadvantages are the rider cannot easily drink from a water bottle (not enough room to tilt the bottle all the way up), the rider's hot exhaled air goes inside the cockpit warming the rider, and when heading into the sun it darkens the interior such that reading the speed odometer is difficult.
Forming is done basically by heating small sections and forcing the foam down on the mold with a gloved hand. Start by doing some minor amounts of bending. Then cut the excess overhanging material to reduce puckering of the edge. Then progressively increase the bends. Bend beyond what you need and cut the excess to get a clean edge. With all these compound curves this piece is very stiff, which helps stiffen the canopy. It’s black to prevent reflections on the inside of the windshield.
This is the canopy with the raised section and the continuation of the black & blue bands of color, which will eventually continue over the turtledeck and down the tail.
Here is the inside of the open canopy. Note the U-shape internal brace. That is the longeron internal brace material (0.2” HD80). It does a wonderful job of strengthening a rather large area canopy. The hinge is a thin strip of canvas material. Note: when contact-cementing the canvas (or any cloth material), first put down a layer of contact cement and let dry, even overnight. Then treat the second coat normally. To get a fine hinge line, I first press a crease along the center of the hinge. I do mine in a smooth jaw vise, but I bet a common house iron would work, too. Because the canopy is so light, there is no need to limit its opening with a string. It simply flops against the side of the shell. The canopy is flipped open when climbing long hills to get additional cooling air.
This shows a front view of the interior of the canopy. On the left is a black strip of HD80 material used as a tongue that engages a matching groove in the entry door. This also stiffens that rather floppy edge. Rule: All unsupported edges need to be stiffened. Also, note the two latches, one in the center to pull the canopy tight up against the shell, and one on the side, which secures the canopy to the door.
Here is a close-up of the center latch. The commercially available latches are way too big and heavy, so latches were fabricated from aluminum. The wire is from a Chinese take-out container. On the OFS, Velcro was used for fasteners. Velcro is light and simple to use but is not secure enough in a crash, which can expose the rider to road rash and causes the shell to come apart and even tear.
The windshield was not cut and mounted until after the vehicle went through initial road testing.
The canopy took three long days of effort. Much of the time was spent sketching and thinking of various solutions to individual problems. The old rule, think and measure many times, and (hopefully) cut only once, worked quite well. I am pleased with the way the canopy turned out. Quite an improvement over the OFS, but it was the OFS from which I learned a lot. Three days of effort may sound excessive, but I have been running the OFS for six years, so the payback is worth putting in the initial effort.
Next section: Tail