Specifications of historical Thread Standards

British fine thread for clocks and optical devices. The flank angle is 47.5°.

Thread No.Major Diameter
mm
Major Diameter
Inch
Pitch
mm
TPITapping Drill Size
mm
100.2540.0100.0644000.173
110.2790.0110.0644000.198
120.3050.0120.0733500.212
130.3300.0130.0733500.237
140.3560.0140.0853000.247
160.4060.0160.0853000.298
170.4320.0170.1022500.302
180.4570.0180.1022500.327
190.4830.0190.1022500.353
200.5080.0200.1212100.353
220.5590.0220.1212100.404
240.6100.0240.1212100.455
260.6600.0260.1411800.480
280.7110.0280.1411800.531
300.7620.0300.1411800.581
320.8130.0320.1411800.632
340.8640.0340.1691500.647
360.9140.0360.1691500.698
380.9650.0380.2121200.694
401.0160.0400.2121200.745
451.1430.0450.2121200.872
501.2700.0500.2541000.945
551.3970.0550.2541001.072
601.5240.0600.2541001.199
651.6510.0650.318801.245
701.7780.0700.318801.372
751.9050.0750.318801.499
802.0320.0800.423601.490
852.1590.0850.423601.617
902.2860.0900.423601.744
952.2860.0950.508501.636
1002.5400.1000.508501.890
Thury Thread