ME Model Engineer Thread

The British Model Engineer Thread is based on the Whitworth thread with a pitch of 32 and 40 TPI. A commercial use of this standard does not exist.
The flank angle is 55°.

Thread Size Diameter
Inch
Diameter
mm
Tapping Drill Size
mm
TPI Pitch
mm
ME 1/8" 1/8 3.175 2.362 40 0.635
ME 5/32" 5/32 3.969 3.155 40 0.635
ME 3/16" 3/16 4.763 3.949 40 0.635
ME 7/32" 7/32 5.556 4.743 40 0.635
ME 1/4" 1/4 6.350 5.333 32 0.794
ME 1/4" 1/4 6.350 5.537 40 0.635
ME 9/32" 9/32 7.144 6.127 32 0.794
ME 9/32" 9/32 7.144 6.330 40 0.635
ME 5/16" 5/16 7.938 6.920 32 0.794
ME 5/16" 5/16 7.938 7.124 40 0.635
ME 3/8" 3/8 9.525 8.508 32 0.794
ME 3/8" 3/8 9.525 8.712 40 0.635
ME 7/16" 7/16 11.113 10.096 32 0.794
ME 7/16" 7/16 11.113 10.300 40 0.635
ME 1/2" 1/2 12.700 11.683 32 0.794
ME 1/2" 1/2 12.700 11.887 40 0.635