Dealing with hull blisters
Patrick Childress discusses fixing blisters, step-by-step, including the history of blister repairs on his sailboat Brick House, a 1976 Valiant 40. A boat from "the blister era" of fiberglass boats. These boats developed blister problems when the fiberglass resin did not set up properly causing not osmosis blisters, but, "resin blisters." These are large blisters in the fiberglass that have become not just cosmetic, but quite possibly structural problems. See more videos at his YouTube channel.