I realize I'm a little late to the game here...regarding transferring to plywood from any of the fullsize plans. The plans I have also have nested fullsize plans, or nested *tiling* of a single large part. Transferring to plywood is simple enough. My biggest decision was to poke holes in my plans, to avoid the use of carbon paper. It wasn't as traumatic as my first thoughts made it out to be. I poked holes in the corners of *straight runs*, and then transferred those *corners* through, onto the plywood, with a pencil or Sharpie, making sure to rig up a way to keep the paper from shifting on the plywood during the process. A few guide reference marks may help to confirm that the paper edge has not shifted on you. Once the dots for the straight lines are transferred from the poked holes, then connect those dots on the plywood for the straight runs with a good straight edge. For the cambers (curves), I poked holes every 4 to 6 inches (10 to 15 cm), and then used a batten to connect those dots with a fair line. I could do it by eye, but a good batten that is known to bend in a *fair* way, removes doubt. If some dots on a curve were off a few millimeters, that's typically alright as long as the batten is *fair* along the dots. Try to get the end points of a curved section spot on for anchoring your fair batten for the entire curve. you can use weights to hold the batten in place, but keep in mind that you want the batten to assume a natural *fair* bend along the dots. Some put screws into the plywood at key dots (or appropriately near them) so they don't feel like they are playing twister to hold the fair batten in place. The holes will be filled for finishing anyway unless you are considering bright finishing some sections. Plan accordingly, then get a helper or two to help hold the batten in place for long curved edges.
The only exception I can think of to mention is to make sure you don't transfer a straight line where a slight camber is called for. I've found that any bateau plans I've used do make that clear in one way or another. There are times when a slight camber on a frame doesn't just *look nice*, but also helps the plywood bend better for that area. You can make sure a line on the plans is straight, by laying a stiff straight edge on the plans to check. Nested lines might present optical illusions. A good straight edge removes doubt.
Some builders have used cheap plywood or some other material to make templates, for every part, and then when the template is confirmed correct, use that to trace to the actual build plywood. I made some posterboard templates for some parts. I could do that on the kitchen table or floor without dragging plywood into the house. Handy when the actual build area is not climate controlled. For me, it was much easier this way, and those templates were later used as guides for marking and cutting fiberglass. But if you make posterboard templates for long parts that need multiple sheets taped together, do that carefully so it does not become another step in the process where error can creep in. Don't ask me how I know....
For long parts that use butt blocks, be sure to put the butt blocks on the correct side, or you may end up with two starboard sides instead of a starboard and a port side. Yeah. That one wasn't me, but sure has been done more than once.
By now you may have all your parts cut already. If so, hopefully this will help future builders with the same question(s).
Welcome to the community and congratulations on the boat choice.
Sail Boats 15' and up. Please include the boat type in your question.
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