building the frames
There are two methods for building a dory: construction using a strong back, which involves building what is essentially a mold for the shape of the boat on which the hull is build; and a free-form build, which uses the precisely assembled frames (with measurements and angles taken from the lofting) to create the shape of the hull.
I chose to use the free-form method to reduce the amount of material used in the build and speed up the process. This method also posed a great opportunity to practice getting the measurements and angles right, first try!
october - november, 2020
pulling frame angles off of the lofting
Using the lofting as a guide, the frame angles and measurements were drawn out in full scale. This provided a useful tool for checking the (very critical) angles on the frames before bolting them together.
frame #10 laid out over the angle guides for double-checking before bolting together
the angles pulled from the lofting used to determine the frame bevels
frames cut & ready for assembly
the assembled frames
scarf joints
The hull of a dory is made out of plywood--I used the standard 1/4" ply for the sides and 1/2" ply for the floor. To make the hull I needed a 20' long piece of plywood in each thickness... Of course, plywood doesn't come in 20' sheets, so I had to make my own. But How do you join something like plywood together in a way that won't come apart? Scarf joints!
Scarfing is a method that allows the maximum amount of contact between two surfaces, especially thin ones such as plywood. To make the joint you plane you two pieces down to a zero thickness over a set distance (3" for my 1/4" plywood, 6" for the 1/2") so that they match together to form an even thickness.
The two pieces are epoxied together creating a joint that is arguably stronger than the plywood itself.
top: the two 6" scarf joints laid on top of each other for planing
bottom: can you pick out where one sheet end and the next begins?
a beautiful Japanese plane used for making the scarf
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top: an example of a scarf joint
bottom: a plywood scarf on the finished boat, can you pick it out?