Sharp "V" Thread

Used in the U.S.A. until 1909. The flank angle is 60°.

Thread Size Nominal
Diameter
mm
Tapping
Drill Size
mm
TPI Pitch
mm
1/4" 6.35 4.15 20 1.27
5/16" 7.94 5.50 18 1.41
3/8" 9.52 6.78 16 1.59
7/16" 11.11 7.97 14 1.81
1/2" 12.70 9.04 12 2.12
9/16" 14.29 10.63 12 2.12
5/8" 15.87 11.87 11 2.31
11/16" 17.46 13.46 11 2.31
3/4" 19.05 14.65 10 2.54
13/16" 20.64 16.24 10 2.54
7/8" 22.22 17.34 9 2.82
15/16" 23.81 18.93 9 2.82
1" 25.40 19.90 8 3.17
1 1/8" 28.57 22.29 7 3.63
1 1/4" 31.75 25.47 7 3.63
1 3/8" 34.92 27.58 6 4.23
1 1/2" 38.10 30.76 6 4.23
1 5/8" 41.27 32.47 5 5.08
1 3/4" 44.45 35.65 5 5.08
1 7/8" 47.62 37.84 4 1/2 5.64
2" 50.80 41.02 4 1/2 5.64
2 1/8" 53.97 44.19 4 1/2 5.64
2 1/4" 57.15 47.37 4 1/2 5.64
2 3/8" 60.32 50.54 4 1/2 5.64
2 1/2" 63.50 52.50 4 5.64
2 5/8" 66.67 55.67 4 5.64
2 3/4" 69.85 58.85 4 5.64
2 7/8" 73.02 62.04 4 5.64
3" 76.20 63.64 3 1/2 7.26
3 1/8" 79.37 66.81 3 1/2 7.26
3 1/4" 82.55 69.99 3 1/2 7.26
3 3/8" 85.72 72.18 3 1/2 7.82
3 1/2" 88.90 73.36 3 1/2 7.82
3 5/8" 92.07 78.53 3 1/2 7.82
3 3/4" 95.25 80.59 3 8.47
3 7/8" 98.42 83.76 3 8.47
4" 101.60 86.94 3 8.47