Carve your canopy buck, cut the bottom end off a 2 litre flat sided PET bottle , wedge the buck in place with a large piece of lumber under the buck, start shrinking with the heat gun. Thats the bit that takes practice, work slowly. It will take a couple of attempts until you get the feel for the shrinking.Both of these cowls and the canopy shown are from soda bottles . Also you can make wheel pant halves, wing tips etc.using this method.
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