Aloha everybody,
I am shaping my first shortboard which will be 5'4x19'1/4x2'2/4. I chose the thruster fin position for my first surfboard but I have some questions as I am a bit confused. In some article, they say toe-in is about 1/4 inches. But if I applied McKee formula I have more than 1/4 inches as toe-in. Could you tell me if I am applying well the formula and good fin placement or should I go with standard 1/4 inches toe-in. What is the impact of high toe-in value more than 1/4 inches?
By applying this formula according to McKee's table chart, I have:
HBF distance from the stringer to rear lateral fin, given by McKee Chart. So at 27,1 cm (10-11/16"), so I have HBF=38,8/2-2.54 = 16.86cm (6.63 inches)
LT: Surfboard lenght=5'4=162.56cm. d = fin lenght = 11.5cm. a= FIN DIRECTION COMPENSATION (giving by McKee chart)
So to calculate the fin toe-in, I applied this formula:
LBF=(LT-DFT-d)*((HBF-a)/(LT-DFT))+a
At the end I have LBF=15.52cm. So toe-in = HBF-LBF=16.86-15.52 = 1.34cm (0.52 inches)
Regards,
Eric.