One thing I was taught about making carved top instruments is to take your time. Carve plates as far in advance as you can. Let them move and distort as they wish and fit them to the ribs in the shape they wish to be rather than forcing them into a shape you’d prefer.
Most of these plates were carved years ago. They’ve moved from workshop to workshop, country to county. As the orders come in, they’re replaced.
So, I take a top down from the wall, and see what it wants to do. The top tells me how thick it wants to be by how it reacts under pressure. Its not a “one size fits all” situation. I wish it was. Once the thicknessing is done by hand, I cut, fit and glue the spruce braces in place. These braces are further shaped after gluing to remove as much mass as possible without compromising the stiffness I want.
So, then after a couple more weeks of sitting on the shelf, the braced soundboard is glued to the ribs.
The next step is binding.