Engineering Tables/Metric Threads

Nominal Diameter (mm) Choice Thread Pitch Series Tapping Drill (mm) Clearance Drills (mm)
Tight Fit Free Fit
11st0.20Fine0.801.051.20
0.25Coarse0.75
1.12nd0.20Fine0.901.151.30
0.25Coarse0.85
1.21st0.20Fine1.001.301.50
0.25Coarse0.95
1.42nd0.20Fine1.201.501.70
0.30Coarse1.10
1.61st0.20Fine1.401.702.00
0.35Coarse1.25
1.82nd0.20Fine1.601.902.20
0.35Coarse1.45
21st0.25Fine1.752.202.60
0.40Coarse1.60
2.22nd0.25Fine1.952.402.80
0.45Coarse1.75
2.51st0.25Fine2.152.703.10
0.45Coarse2.05
31st0.35Fine2.653.203.60
0.50Coarse2.50
3.52nd0.35Fine3.153.704.20
0.60Coarse2.90
41st0.50Fine3.504.304.80
0.70Coarse3.30
4.52nd0.50Fine4.004.805.30
0.75Coarse3.70
51st0.50Fine4.505.305.80
0.80Coarse4.20
5.53rd0.50Fine5.005.806.40
61st0.75Fine5.256.407.00
1.00Coarse5.00
72nd0.75Fine6.257.408.00
1.00Coarse6.00
81st0.75Fine7.258.4010.00
1.00Fine7.50
1.25Coarse6.80
93rd0.75Fine8.259.5010.50
1.00Fine8.00
1.25Coarse7.80
101st0.75Fine9.2510.5012.00
1.00Fine9.00
1.25Fine8.80
1.50Coarse8.50
113rd0.75Fine10.2512.0013.00
1.00Fine10.00
1.50Coarse9.50
121st1.00Fine11.0013.0015.00
1.25Fine10.75
1.50Fine10.50
2.00Coarse10.20
142nd1.00Fine13.0015.0017.00
1.25Fine12.80
1.50Fine12.50
2.00Coarse12.00
153rd1.00Fine14.0016.0018.00
1.50Fine13.50
161st1.00Fine15.0017.0019.00
1.50Fine14.50
2.00Coarse14.00
173rd1.00Fine16.0018.0020.00
1.50Fine15.50
182nd1.00Fine17.0019.0021.00
1.50Fine16.50
2.00Fine16.00
2.50Coarse15.50
201st1.00Fine19.0021.0024.00
1.50Fine18.50
2.00Fine18.00
2.50Coarse17.50
222nd1.00Fine21.0023.0026.00
1.50Fine20.50
2.00Fine20.00
2.50Coarse19.50
241st1.00Fine23.0025.0028.00
1.50Fine22.50
2.00Fine22.00
3.00Coarse21.00
253rd1.00Fine24.0026.0030.00
1.50Fine23.50
2.00Fine23.00
263rd1.00Fine24.5027.0031.00
272nd1.00Fine26.0028.0032.00
1.50Fine25.50
2.00Fine25.00
3.00Coarse24.00
283rd1.00Fine27.00XX.00XX.00
1.50Fine26.50
2.00Fine26.00
301st1.00Fine29.0031.0035.00
1.50Fine28.50
2.00Fine28.00
3.00Fine27.00
3.50Coarse26.50
323rd1.50Fine30.50XX.00XX.00
2.00Fine30.00
332nd1.50Fine31.5034.0038.00
2.00Fine31.00
3.00Fine30.00
3.50Coarse29.50
353rd1.50Fine33.50XX.00XX.00
2.00Fine33.00
361st1.50Fine34.5037.0042.00
2.00Fine34.00
3.00Fine33.00
4.00Coarse32.00
383rd1.50FineXX.50
392nd1.50Fine37.5040.0045.00
2.00Fine37.00
3.00Fine36.00
4.00Coarse35.50
403rd1.50Fine38.50
2.00Fine38.00
3.00Fine37.00
421st1.50Fine40.5043.0048.00
2.00Fine40.00
3.00Fine39.00
4.00Fine38.00
4.50Coarse37.50
452nd1.50Fine43.5046.0052.00
2.00Fine43.00
3.00Fine42.00
4.00Fine41.00
4.50Coarse40.50
481st1.50Fine46.5050.0056.00
2.00Fine46.00
3.00Fine45.00
4.00Fine44.00
5.00Coarse43.00
503rd1.50Fine48.50
2.00Fine48.00
3.00Fine47.00
522nd1.50Fine50.5054.0062.00
2.00Fine50.00
3.00Fine49.00
4.00Fine48.00
5.00Coarse47.00
553rd1.50Fine53.50
2.00Fine53.00
3.00Fine52.00
4.00Fine51.00
561st1.50Fine54.5058.0066.00
2.00Fine54.00
3.00Fine53.00
4.00Fine52.00
5.50Coarse50.50
Notes:
  1. Nominal diameters, pitches, series and choices as specified in ISO 261.
  2. The Coarse Series is the preferred series. The Fine Series is to be used only when the Coarse Series is not suitable due to wall thickness or other space considerations.
Category:Book:Engineering Tables#Metric%20Threads%20
Category:Book:Engineering Tables