Stiffness and Rebound??

[ezglyder]

Hello Force Fin,
How is the stiffness and rebound of the fins determined? I love the fin, just want to know more about it.
Thanks,
ezglyder

 

[Bob Evans]

EZGLYDER, Thank you for your question. Stiffness is measured using a durometer, when poked into the fin will give the shore hardness, a measurement of softness or hardness of a material. We test at 86a for the orginal Force Fin and 92a for the Pro model of Force Fin. We make a special Force fin for divers with impaired kick strength at 72a which we call or giggle wiggle fin material. The specified durometer of all our fins is based upon my more than 30 years of designing and testing fins. The rebound of our hand cast Poly-Urethanes is another story. It is part of the polyurethane chemistry mixture we use. Rebound, or SNAP is key to how all of my Force Fin designs propel you. The cost to obtain performance is high therefore the much higher cost of our fins. Try to flip your fin's and see how high they jump up. Put the foot pocket down on a table and then pull back the fin blade to make a good fin kick and let the fin go. Force Fins will bounce several feet into the air. Other fins kind of flop back down on the table. We have worked for over 30 years perfecting our formulations which give back more than any other fin around. The 16 hours of heat treating at 240 brings the good stuff out in our fin's. Go enjoy what we put into our American Made products. Best Bob

 

[Blair Mott]

You want to understand rebound or snap. Try to reproduce the height seen here from snapping a different variety of fins off your knee! Bob is snapping a Tan Delta Excellerating Force Fin excel_force_fin_product off his knee at the 2008 DEMA show in Las Vegas.

When you are finished with your down / power stroke in the kick cycle the material used in Force Fins gives you that extra snap with out moving your leg.

 

[ezglyder]

I really appreciate the explanation of stiffness and rebound. My "guess" at what they are wasn't even close. Thanks for the "flip test" , too. That's a hoot.
Most of all, Thank You, for a fin that's compact enough to fit in a carry-on, can be used with or without a boot (two fins in one), energy efficient, and just too tough to tear-up.
Best Regards,
ezglyder