Stitch and glue

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The terms stitch and glue, tack and tape, and stitch and tape all refer to a construction method used by many amateur boat builders.

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[edit] History

The stitch and glue method was developed by woodwork teacher Ken Littledyke for the manufacture of canoes, using plywood panels joined by fiberglass tape and resin. The technique was then popularised by the first TV DIY expert, Barry Bucknell, in about 1964 (in fact, Barry Bucknell invented the term DIY, making him, by definition, the first DIY expert). The method was adopted, substituting copper wire ties rather than fishing line as in the early Littledyke examples, for the construction of the Mirror Dinghy. The Mirror is so named because the design was sponsored by The Daily Mirror newspaper, a fact reflected by the historically red sails. The Daily Mirror apparently wanted to bring cheap sailing to the masses. As such, unlike other construction techniques of the day, which required specialist skills and tools, Stitch and Glue was supposed to put boat-building within the reach of the average public.

Stitch and glue is similar to a traditional form of boatbuilding from northern Europe, particularly Lapland, called sewn boats. It is not known if Littledyke's development of the stitch and glue methods was influenced by the sewn boat technique.

[edit] Technique

The technique basically consists of literally stitching together plywood panels with some sort of wire or other suitable device, such as the cable tie or duct tape. When stitched together, the cut panels are drilled with small holes along the joining edges, and short pieces of wire are threaded through the holes and twisted together to bring the panels together. Once together, the join between the two pieces is glued and commonly taped over (on the inside of the hull). Thickened epoxy glue is commonly used to close the joint between abutting plywood panels. When the glue is dry, the wire can be removed to leave a smooth outer join; the holes are then filled and sanded over. When a combination of fiberglass tape and epoxy glue, the resulting composite material makes an extremely strong joint. Optionally, the outside of the joint can be taped and glued as well, providing additional strength. True stitch and glue designs generally have few bulkheads, relying instead on the geometry of the panels to provide shape, and forming a monocoque or semi-monocoque structure.

[edit] Spread of the technique

Stitch and glue has become one of the dominant techniques in amateur boatbuilding. While the use of relatively few plywood panels (which minimizes the joints and makes the construction easier and faster) limits the shapes possible, the simplicity and low cost of the stich and glue technique makes it the method of choice among most amateur boatbuilders. Simple software CAD packages are available for designing stich and glue boats, and there are many Internet bulletin boards, newsgroups, and mailing lists dedicated to the subject of stitch and glue boats and various popular stich and glue designs.

[edit] The one sheet boat

The one sheet boat, or OSB, is a an outgrowth of the stitch and glue technique. The OSB is a boat that can be built using a single sheet of 4 foot by 8 foot plywood (1.22 m × 2.44 m). Some additional wood is often used, for supports, chines, or as a transom, though some can be built entirely with the sheet of plywood. OSBs tend to be very small, since the displacement is limited to a theoretical maximum of about 1500 lbs (680 kg), based on the largest hemispherical shape that could be formed with the same surface area as the sheet of plywood. As forming a hemisphere is possible (see geodesic dome) it is not practical, and most designs have maximum displacements of under 1000 lbs (450 kg), and practical displacements only large enough for a single person. One of the more unusual, yet practical OSB designs is "the Dug"[1], an 18 foot (5.4 m) long canoe that can be built entirely from one sheet of plywood. One of the more popular OSB designs is the Mouseboat by Gavin Atkin. The hull of the Mouseboat can be built with a single sheet of plywood, and many variants have been created. The Mouseboat is described by the designer as an open source design; the plans are freely available, and builders are encouraged to experiment with the design and share the results with the Mouseboat community.

[edit] External links