Stringer

Hey this may seem like a dumb question but I can’t seem to figure it out. Anyway I am building a half scale model of a board out of styrofoam. It is supposed to be 1.35 inches thick. I can’t seem to put the rocker in it, so I was wondering is it necessary for me to put a stringer in it or should i just continue to sand away at it.

Put a stringer in it. You can induce the rocker by bending the foam when the glue sets. The stringer will hold the rocker, act as a centerline, and be “anatomically correct”…