Flex Research: Problem#2: Mass...not Weight!

Hey Stoneburner-

Not bad, actually very well done.  3G is realistic.  In the late 80’s I used calibrated clay rods called PlastiGage

under a sheet of plastic, went out and spiked a solid bottom turn and came in.  The amount of PlastiGage 

deformation resulted in a loading of about 4G or just under.  I like your calc, done like an engineer…

…Now the fun part, the applied load is supported, but dynamically supported.  By a wetted footprint of moving

water that has a gradient in two degrees, possibly three. 

 

In simple engineering methods we’d like to substitute a static supporting load for the dynamic distributed

supporting resultant load.  It’s just easier on the mind and can be very revealing.  You will find probably a

centroidal point load, or up to several simple static supporting loads based upon the map of the dynamic

supporting gradient.  What you will find is that the board is both twisting and straight bending.  Depending

upon the surfing scenario, one of those bending modes is good, the other bad (detrimental to performance,

ie. “heavy bogging.”)

 

 

Then from there start to mess with what we may think could benefit a surfer…

 

…HINT:  it’s not the downstroke but the return stroke that matters.

Best regards,

George