Physics Boat- Polyurethane Coating Over Paper?

[Vincent]

For my high-school physics project, we're building boats using wood and paper. The only materials allowed are the aforementioned wood+paper, and wood glue and polyurethane coating. If I were to brush/paint the polyurethane onto the paper, do I have to worry about the paper getting too damp? Should I paint it on both sides of the paper at the same time, or should I coat one side first and then coat the inside after. Also, does the polyurethane make the paper stiff? I'm thinking I should get the paper glued onto the frame before painting, but I'm wondering if it's better to coat the paper first before applying it to the frame. Thanks!

 

[max]

First of of, polyurethane will make it stiff--if you can get it to dry in the shape you want it to. However, it won't be THAT stiff. It's not a structural material. Polyurethane is usually used in conjunction with something else as a coating even though it will stiffen it ever so slightly.

Secondly, it will soak through even if you coat only one side at a time. When that happens, it will ruin the paper and the shape. Your best bet is to make some sort of mold and then apply it so that it maintains shape.