Determine cabin size and configuration by asking the following questions: What will the cabin be used for? How tall will the cabin be? What part of the boat is to be enclosed by the cabin? If the canvas cabin is going to be used to provide privacy for using the bathroom or showering, a relatively small enclosure about 3 feet square and 5 feet tall, with or without a roof panel may be all that is necessary. If the cabin is planned to be used as weekend living quarters, the canvas cabin will need to be larger. When deciding on the size of the cabin, consider all potential uses to which it may be put and build for the use that requires the largest cabin.
Lay out the frame and measure the PVC pipe before cutting. Cut the PVC pipe, using the hacksaw. Assemble the frame. Determine how well the cabin fits in the boat and make adjustments before gluing the frame together. To glue the frame together, remove any grease, dirt and moisture from the ends of the pipe sections and the interior of the fittings where glue will be applied. Apply PVC purple primer. Allow the primer to dry, then apply PVC pipe cement, insert the PVC leg segment into the "T" fitting and turn the PVC pipe (not the fitting) one-quarter turn. For the PVC segments other than legs, again, apply the PVC primer, allow the primer to dry, apply the PVC cement, insert the PVC segment into the "elbow" fitting and turn the PVC segment (not the fitting) one-quarter turn.
Measure the frame and cut canvas panels for the sides, adding 6" to the top measurement, to allow the canvas to be fastened to the frame with the Velcro as shown in the illustrations accompanying Steps 5 and 6. Hem the canvas side panels, using a sewing machine with a size 16 or 18 needle and heavy thread.
Attach Velcro to the canvas. This is best done by having another person hold the canvas panels in place one-at-a-time, then wrapping the top edge around the frame and marking the location for the Velcro strips, then sewing the hook strip of the Velcro and the loop strip of the Velcro to adjacent locations as shown. The canvas panels need to be attached to each other and to the frame. Velcro strips should also be sewn along the sides of the panels that hang down, as shown in the illustration accompanying Step 6, to facilitate enclosing the sides of the cabin.
Measure and prepare the canvas to form the roof panel. The top of the supporting framework will be the size of the canopy. However, since the canvas will lap over the sides of the framework slightly, it will be necessary to measure and cut the canvas one foot longer and one foot wider than the frame. Lay the canvas out on a flat surface and, using a carpenter's square, mark 6-inch x 6-inch squares on the corners of the canvas. With scissors, trim the 6-inch x 6-inch squares from the corners of the canvas, then turn under 1/4-inch and hem all edges of the canvas. (A treadle sewing machine will make quick work of this, but an electric sewing machine may struggle with the canvas.) This will leave a small gap at the corners of the finished canopy, which will minimize the upward force of wind coming through the canopied area. Note the placement of Velcro fasteners in the corners of the roof panel; these will close the notched corners when the roof panel is placed onto the frame, as shown in Step 6.
Hang the side panels. Slide the roof panel onto the top of the frame and center the panel so that the notched corners line up with the corners of the top of the framework. Before moving the roof panel into its final position, close one corner of the roof panel with the Velcro strips to act as an "anchor." When the corners of the roof panel have been secured, use the Velcro strips on the sides of the side panels to enclose the cabin completely.
Drill half-inch holes into the 2" PVC pipe segments. Place the completed frame into the boat at the desired position. Mark the locations of the legs on the deck with a marking pen and remove the frame. Using 2-part epoxy glue, glue the 2" PVC pipe segments---the mounting brackets for the frame--into place and allow the epoxy to cure completely. When the epoxy has cured, slip the legs of the frames into the mounting segments and secure with screws. Attach the canvas, and the canvas cabin is complete.