I have been working on elliptic surfboard design techniques for several years. I came up with an ellipse-based planshape/template method that satisfied me this year.
My ellipse-based panshape started 2 or 3 years ago as a retro fish template that I stretched to make a new template. After a bit, I decided I could use a half-ellipse placed at the surfboard's widepoint for the nose, to get more streamlined curves for the front half of the shape. I was going to combine it with the stretched tail section of a retro fish. After a while longer, I decided I could stretch an ellipse to create the tail section for the planshape. I averaged the widepoint positions, relative to length, from retro fish designs to place the position of my widepoint. I joined the half-ellipses at the location of the surfboard widepoint (purple line). I decided that tail end width (blue line) should be 61.8% of the surfboard's wide point (Golden Ratio). What started as a Stretched Retro Fish became an entirely new ellipse-based planshape.
I have never posted my design or method for this all ellipse planshape before today. I posted the "concept" once in a Sways "computer/CAD hate thread" to prove you could use simple computer programs to create and compare designs from an existing template -- and create entirely original surfboard designs.
Semi-elliptical planshape. I created it with a stretched retro fish tail and a half-ellipse nose joined at the surfboard's widepoint. I posted it in a Swaylocks thread (page 4, post #41):
From Retro Fish to new shape with new dims?
Done quickly with PowerPoint, Photoshop and a computer --"Computer-Aided Design?"
I find the computer useful for exploring design
possiblities ...
Links to the other elliptic surfboard design posts:
Ellipse-based rails
Ellipse-based rocker
Ellipse-based tail template
