Well it's been nearly a year now since I last worked on my Lil' Patriots (Patriot 2, Patriot 3) so feel it's long over due that I revisit this project. Haven't really thought about it for a while but having recently purchased an interesting new surfboard from Gee-Spot Surfboards which is kind of inspired me to take the board in a new direction.
It's a similar build concept, being balsa covered EPS foam under epoxy, though gone a bit fancier with the stringers, nose and tail blocks but more interestingly for me is in the rails.
Unlike the majority of my surfboards, and indeed the preceeding Patriots, the rails on this one a really quite thin. This along with an article which has recently re-surfaced on Swaylocks, http://www.swaylocks.com/forums/thick-board-skinny-rails, has got me to thinking how this could be integrated into my Patriot design.
I've previously realised that buoyancy and wave catching has never really been a problem with the Patriot design which I feel allows me to go a lot more extreme with the volume. With my new solid balsa board being aimed largely at surfing small clean waves I'm now seeing an opportunity for creating a paipo-styled bodyboard more adept in larger steeper waves which is where a thinner Patriot with a lot more rocker could be suited.
So my first practical consideration when designing the 4 is the fact that most of the strength of the last two builds has been in the parabolic balsa rails; with a lot of volume taken out of the rails strength will be greatly compromised.
To take account of this then I've re-profiled the board in Aku Shaper and come up with two designs, of slightly varying thickness and rocker, and transferred them onto paulownia stringers (still want to keep the design as light as possible) which should add a huge amount of structural integrity.