Planned out fin placement and then carved out the slits to insert fin boxes using a dremel (these are imperfect but I did my best). I used a method of calculation that I found published by a famous shaper of quad fin surfboards. http://www.mckeesurf.com/?page_id=267
Luke, in this instance, why the choice for quad fins? What are the benefits over double fins or a single fin? Are there any things you lose on the performance side by have quad fins?