AppShip 4 was a shorter project with 6 participants who built a 12ft canoe in June 2011
Here are some of the photos of the build which took place in Bedlington Community High School, Northumberland, UK http://bchs.uk.net/

This canoe was built using the "stitch and glue" method of plywood fabrication where the planks are joined with wire "stitches" then glass fibre tape is applied to the interior seams. Once the taped seams have set the wire stitches can be removed and the exterior sheathed in fibre glass cloth.

A series of 3mm holes are drilled at intervals along the edge of each plank, these must correspond to the holes in the adjecent plank. It is quite easy to end up with the small holes for the wire being out of alignment so it is best to start with just a few holes to hold each plank in place, then once you are confident that the plank is accurately aligned at the bow / stern the remaining holes and stitches can be drilled and wired. The ends of the wires are a bit sharp and will scrape skin and could pull threads out of clothes, so take care.

While the planks are held together with the wire stitches the shape of the boat is very weak and unstable requiring temporary molds fixed inside to prevent the "pea-pod" shape from closing up or sagging too low in the middle.

Inserting extra molds will give a more fair curved shape with fewer "hard-points" (sections that are straighter), but while this gives a guide for the rough shape, it is the tensioning of the wire stitches and the careful easing of plank edges that will address any bulges where the individual planks come together. In this photo above, the bow (at the bottom of the screen) has a clear kink where the top planks are misaligned with the bottom planks. This sort of misalignment will gradually be pulled out by tensioning (and easing) the stitches, however, adjusting one plank will effect others so you may have to fix sections more than once.

The wibbly wobbly bow can be clearly seen here and while it was adjusted, if you look closely at the finished canoe at the bottom of this page a tiny kink is still there. These planks were cut by young people learning to use a jigsaw and the small wobbles in the edges of the planks tend to combine to create hollows and bulges when the planks are stitched together. This is not a problem for this particular project, but if you are building your own boat you may want to develop an interal Jig to ensure that the planks and shape has greater support during the wiring and taping the seams.





















































































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