Not sure if this has been posted before. But I just got the current issue of Surfers Journal, a very good issue by the way. And it has an two page spread of some beautiful hollow wooden boards by Lon Klein. Look to be pressed into shape with fiberglass tooling (molds) using car jacks.
So I went online to seach and found this page:
http://www.haleiwasurfboard.com/haleiwa-surfboards-process.html
Enjoy.