SPRINGS 



143 



stress. For any other fiber stress, divide the selected fiber stress by 50,000, take the 

 square root of this ratio, and divide the diameter d obtained from the chart by this 

 factor. 



Step 3. To determine deflection per coil or per turn. 



The chart is based on 50,000 lb. per sq. in. fiber stress and 11,500,000 for G, the 

 modulus of elasticity in shear. For other values of maximum stress and modulus of 



CHART TO DETERMINE DEFLECTION PER COIL 



4 5 6 7 8 8 9 10 II 12 13 14 15 16 17 18 19 20 21 

 Ratios of Outside Coil Diameter to Wire Diameter, t- 



elasticity, the deflection factor will be directly proportional to the stress and inverseh^ 

 proportional to the modulus of elasticity. 



Determine the deflection factor for given ratio D/rf, correct for fiber stress and 

 elastic modulus, multiply by d, the diameter of the wire. 



