The first step was to make the form. I had the measurements from the last time I did a sit-test on the frame, so first I made a paper pattern. This was made easy by using a piece of my wife's dress-pattern paper that has a 1 inch grid on it.
I needed a way to make clean curves. Luckily I had a test rib that had just the right sharp curves and an extra rib blank that bent nicely for gentle curves. I did one side and then folded it in half and cut both sides together. (Then realized I'd forgotten to show the marking process and staged these pix)
Transferring to plywood was easy. So was cutting it out on the band saw.
Finally I drew a line 1 1/2 inches in from the edge and used a hole saw in my drill to make places to put clamps all around the edge. I don't scuba-dive any more so my dive weights have migrated to the work shop. A dive weight worked nicely to keep the plywood from spinning around when the hole saw caught.
I needed a nice smooth wedge on both ends of each strip so I could scarf them together.
This simple jig with a wedge at the right angle and a bit of scrap to support the strip let me use the jointer to trim the angle. Biggest problem was figuring out how to hold the jig together while doing the trimming. Look at that nice sloped cut - and all of them came out at precisely the same angle!
The copper pan I used for the ribs was too short, so I hot-glued a foam trough and lined it with plastic. The first step was to soak the strips overnight.
Then dump the cold water out. I made the end removable specifically so the trough can be emptied.
I boiled up a big pot of water on the kitchen stove, poured it in the trough, covered and let steep for 5 min. With the cover off you can see the steam rising. Another convenient dive weight holds the strips under water. Note that the plastic both made it water-tight and kept the hot water from melting the hot-glue.
Then I put on some gloves and used pretty much every clamp I owned wrapping the strips around the form.
After letting the strips sit for a couple of days, I took the clamps off, put a strip of waxed paper around the form, and had a horrible time epoxying them all together. My fault - I had a hard time finding waterproof clear epoxy in medium sized containers. I didn't want to buy either little box-store two-part syringes (would have needed a stack of them) or quart cans that would have been mostly wasted. Finally found some medium sized bottles but skipped over the fact that they were 5 minute epoxy. It harded faster than I could get everything clamped together.
That got the tall part of the coaming done (here partly trimmed up). Now I needed to do the outside rim that the spray skirt will hook over. I just happened to have several left over rib blanks that are the perfect size. (I had made extra 'cause I expected some to break while bending - but none did!)
They are too small for the jig so I used my plane to make nice wedge-shaped ends for scarfing.
Another round of heating, bending, letting sit, gluing and I'm ready to do the final shaping.
Smooth up the top and bottom with the plane and round the edges with the spoke-shave.
Finish up with scraper, file, and sand-paper. I guess it's not bad for my first laminating job. I could wish for better but I'm not going to do it over.
It sits perfectly on the edges of the deck beams.
The final two frame pieces are the the two deck stringers (the two pieces down the middle on top). Then a some finishing work and lash the whole thing together!
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