the information may be old but still relevent ,as traditional floats are still made pretty much the same ways as in the book .i’ve even made a float using a template/former from the book ,i knocked up this one as a test and got pretty good results.with a bit of refinement
you would have a really goodway of douplicating the shapes.


you get a round bar of wood ,and carve the float shape in relief then line it with sanding paper ,this is facilitated by cutting slit’s into the sanding paper making it conform to the shape easier.Yhis method can be used too make even small bodies like pole floats ,and works with both balsa and foam