[Fordors]

The "old toolmaker" way to determine what diameter rod is used for machine screw sizes is to take the number size and times it by .013 and then add .060. Example for 10-32 is 10 X .013 = .130 + .060 = .190; .190 being close to 3/16 so the #10 screws are that size. The 12-24 screw would be 12 X .013 = .156 + .060 = .216; .216 is just under 7/32.