The first two hatch covers that I built were nearly identical, even sharing two of the three critical dimensions. The final cover, the one that covers our butterfly hatch (called that because when the flaps are open it looks like a perched butterfly, I suppose) is completely different.
This cover has two ends which are vaguely "house" shaped and one long piece that drapes from one side, over the top, and down the other side. The old cover was in really sad shape - that long piece had shrunk up width-wise from 22" (the width of the hatch) to less than 20", pulling the two end pieces way up. But I determined that the two end pieces were roughly the correct size and shape, so I disassembled (really easy - the thread was completely rotten) the cover and made a pattern (using Sailrite Duraskrim) from an old end piece.
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| An end piece pattern is made! |
Then, to get the real length of the long center piece (not trusting the shrunken old piece), I simply measured the circumference of the relevant edges of the pattern, allowing an additional 2" for a hem at the bottom of each end. Then I stitched the whole thing up using my trusty LSZ-1.
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| Trial fitting |
The trial fitting proved satisfactory, so I proceeded with the windows, again using Strataglass. First it was necessary to layout the location and size of the desired openings, and then add a line 1" away on the outside all the way around to make a "fold-to" mark; to make a finished edge where the fabric meets the vinyl, I wanted to fold the edge under 1/2" for a hem.
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| Layout for the windows |
After using a hot knife to make the cutouts and the corner notches (to allow the folding under of the hems), the cover lost a lot of its structural integrity - it became very floppy! I had anticipated this, and so before I made those cutouts, I measured the diagonals from the opening corner marks for future reference.
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| Floppy! |
To make the hems, I pre-creased the edges to the lines and then applied Sailrite's Seamstick basting tape inside the creases to hold the folds in place. I then made another application of Seamstick to the hems, but left the release paper in place. I laid the Strataglass over the openings, arranging the canvas so that the Strataglass and canvas were shaped properly... using those diagonal measurements I took before I made the cutouts. Then I carefully pulled the release tape out from under the Seamstick, fixing the Strataglass to the cloth and stabilizing the shape (the Seamstick not only serves to hold things in place for stitching, but it also serves as a water seal in the hem). Then a double round of stitching to make it all permanent. Lather, rinse, repeat for the other window.
Finally, installation of snaps to match the studs on the hatch completed the project.
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| Done! |
