As Eric recommends in the videos, you should precoat the plywood parts of the frames and every other component that you can with at least two coats of epoxy, sanded, before installing the components. That precoating should include finish coats of paint when possible. The inside of this boat includes hull planks, stringers, chine logs and sheer strakes, floors and frames that are dramatically easier to coat and sand before they are glued together into a welter of small areas that are hard to reach and hard to sand. I did not begin precoating at the outset of my project and regret it. :-)