Originally posted by AMGRacer
Still here. No idea about those rates.
I suppose you could work it out - a bit fiddly though. Also, the thickness of the paint makes it practically impossible to get an accurate reading of the wire diameter.
Measure the diameter of the wire, the number of free coils, the outside diameter of the coils and apply this:
p = (G * F * d^4 ) / ( 8 * N * ( D - d )^3 )
p = rate in lbf/in
G = torsional modulus of elasticity = 11.5 * 10 ^ 6 for most spring steels
d = wire diamter (inches)
N = number of working coils
D = outside diameter (inches)