Kaimusailing

The offsets for the 12 foot ama were entered in a text file. Then they were used to cut out paper patterns of the hull sides and bulkheads. The inboard hull side is raised about 1 1/2 inches to meet the outriggers as they arch down and attach to the gunwales. At the 12:1 scale this difference is only about an eighth of an inch.
.
The paper patterns for the model ama hull sides were test fit on a scale 4X8 plywood sheet (also paper) and both sides of the 12 foot ama can come out of a single sheet of 3 mm door skin, readily available at the local lumber store. There is about 8 square feet of leftover that could be used for butt blocks and any other small thin ply parts.
.
I reviewed lots of small boat building websites and also John Gardner’s book on building small craft. On the CLCBoats.com site are instructional videos for strip planking. The fellow demonstrating technique is Nick Schade (I think). He shows the whole process from cutting the thin strips out of a plank, surface planing, matching grain, and organizing the strips so that they don’t get out of order. The end result is beautiful, but the process is tedious.
.
There are also sites that show tortured ply construction, not many. I think the technique I used a couple years ago is difficult to improve. I assembled the flat hull panels with butt joints between sections of the hull side, left unjoined, but joined together by sheer stringers that ran the whole length of the hull side. I planned to put them outboard where they can be used to help clamp the deck and also help deflect spray. The hull sides are laid on top of each other and wired along the keel from knuckle to knuckle, then opened up, and bulkheads forced down into the hull with spanish windlass attached to the gunwales, over the top of the bulkhead. Tightening the windlass draws the gunwales, which have been strengthened by the sheer stringers, against the bulkhead, as well as pushing the bulkhead into the hull and forcing the hull sides into shape.
.
The problem with making a double ended hull shape with tortured ply is that any seams in the hull panels are not straight lines and are a difficult curve to predict. By leaving the seams unjoined until after the hull is forced into shape, the seams can be trimmed to fit. It is no problem to wind up the windlasses several times to force the hull into shape, then mark, then unwind, cut, then wind up again to check, and finally glue the butt blocks and join the panels when all is tried and true.
.
Oops! I meant to post this as soon as I had some photos of the model and I had to go out and get more supplies, no photos yet..
.
A search of “proa model” brought up Astrid Obonaga’s DESDE PROA as the first image. It is available for purchase at saatchiart.com. Other images came up, but would not be appropriate for this sailing site. I will peruse them further.