Hello ! to do a clear contour like that Do you use only resin ...no cloth???
you definitly want to be using cloth, there are a few diffrent ways of doing it, if you search around here you will find some posts about it
CanadianSurfer, It is done by running the outside plys long past the fin and filling the gap with roving all wetted out. Let it kick, shape to size, polish out. Definitely done with alot of glass.