Boatwright Series: Building a classic Chaisson 10’ Dory
Instructor: Bruce Campbell
January through April 17, 2016
The dory chosen for a glued lap construction using the Thomas Hill glued lap method, was originally built by George L. Chaisson of Swampscott Massachussets circa 1916. The round hull, multi-plank design is often referred to as a “Swampscott Dory.” The round hull is a more efficient displacement hull design than, for example, the simpler flat planked “Grand Banks Dory.” Examples of both are laid out by John Gardner in “The Dory Book,” 1987. The class relied on Gardner’s illustrations, measurements, and table of offsets to recreate the craft.
Classes included “Lofting,” or drawing full sized plans, constructing a mold from the lofted design, laminating the stem, fashioning a transom, attaching them to the bottom, planking the hull, and fitting outwale, inwale, and seat frames.
Lofting the full size boat from the Table of Offsets. The skill allows the boat builder to choose from hundreds of designs without needing to buy patterns or kits. Larry Fogelson (with coffee), Stanley Madsen, Sarah Madsen (with hammer), Jason Fails far right.
Using the lofted half-breadth and heights to project the transom dimensions.
A batten is held to the nails and a “fair” curve is drawn to illustrate the hull. Jason Fails, Lorien, Sarah Madsen holding the sheetrock T-square, and Andy Reynolds far right.
Using 16 gauge Raptor 5/8” long Composite nails to hold the planks while the epoxy cures. The composite nails can be planed or chiseled without damaging tools.
Jason Fails and Seth Wilson cleaning up epoxy squeeze-out between the bottom and the garboard planks.
Seth Wilson uses a heat gun to remove excess epoxy squeezed out between the bottom and the garboards.
Making the “Gain Cut” to blend the planks at the transom and stem.
Adding sawdust thickened epoxy to the plank bevel and transom.
Attaching the epoxy coated plank #3 to underling glued beveled plank. (Planks are conventionally held in place with “Lap Clamps.” The class successfully tested the use of composite nails to hold the planks while the epoxy cures. The composite nails held sufficiently to allow one to attach more than one plank at a time, before the epoxy set. Bruce Stephenson, Stanley Madson, and Seth Wilson with nail gun.
Bottom, Garboard (plank 1), Broadstrake (plank 2), and Binder (plank 2) are glued together and to the stem and transom.
Removing the completed hull from the mold. The battens and mold stations are ready for use building the next hull.
Bruce Campbell sits in the completed hull prior to seats and trim. The strength of this construction style comes from the use of modern plywood and epoxying the beveled joints. The light weight results from the absence of ribs and stringers in the completed hull.
The outwale is clamped to the top sheer plank. Seat frames are clamped and epoxied in place.
The outwales and inwales are attached and join the transom with a knee fashioned to serve as a handle to lift the boat.
The bowplate or breasthook is clamped in place.
First test run at Hamme Pool.
VeraAnn and Bruce Campbell, rowing, on the Tanana River, Alaska
Reindeer Hills, Nenana River, Alaska, summer 2016.
Fishing with the Chaisson 10’ Dory, September, 2016, on Chena Lake, Alaska.