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How To Cut Threads ~ Using Taps and Dies

Thread Cutting - Using Taps and Dies

This 4-minute video will give you the essential info required to cut threads and keep yourself from getting into trouble.

Both Imperial and Metric tap drill bit sizes are charted below.

If you need a tap and die set on the cheap, get the Harbor Freight Set(s). We’ve had our current 45 pc SAE and Metric sets (~$85 each) in regular shop use for better than four years now. We’ve lost a couple, but haven’t broken any. With proper cutting fluid use, they’ve stayed sharper than expected.

Alternately, Amazon offers several affordable Tap and Die set options.

Tap Drill Chart and Reference

Imperial Tap Drill Chart

Machine Screw Size Number of Threads Per Inch Minor Dia. Tap Drills Clearance Hole Drills
Aluminum, Brass & Plastics 75% ThreadStainless Steel, Steels & Iron 50% ThreadAll Materials
Close Fit Free Fit
No. or Dia. Major Dia. Drill Size Decimal Equiv. Drill Size Decimal Equiv. Drill Size Decimal Equiv. Drill Size Decimal Equiv.
0.060080.04473/64.046955.052052.063550.0700
1.073064.053853.05951/16.062548.076046.0810
72.056053.059552.0635
2.086056.064150.070049.073043.089041.0960
64.066850.070048.0760
3.099048.073447.078544.086037.104035.1100
56.077145.082043.0890
4.112040.081343.089041.096032.116030.1285
48.086442.093540.0980
5.125040.094338.10157/64.109430.128529.1360
44.097137.104035.1100
6.138032.099736.106532.116027.144025.1495
40.107333.113031.1200
8.164032.125729.136027.144018.169516.1770
36.129929.136026.1470
10.190024.138925.149520.16109.19607.2010
32.151721.159018.1695
12.216024.164916.177012.18902.22101.2280
28.172214.182010.1935
32.177713.18509.1960
1/4.250020.18877.20107/32.2188F.2570H.2660
28.20623.21301.2280
32.21177/32.21881.2280
5/16.312518.2443F.2570J.2770P.3230Q.3320
24.2614I.27209/32.2812
32.27429/32.2812L.2900
3/8.375016.29835/16.3125Q.3320W.3860X.3970
24.3239Q.3320S.3480
32.336711/32.3438T.3580

7/16

.4375

14.3499U.368025/64.3906

29/64

.4531

15/32

.4687

20.376225/64.390613/32.4062
28.3937Y.4040Z.4130
1/2.500013.405627/64.421929/64.453133/64.515617/32.5312
20.438729/64.453115/32.4688
28.456215/32.468815/32.4688
9/16.562512.460331/64.484433/64.515637/64.578119/32.5938
18.494333/64.515617/32.5312
24.511433/64.515617/32.5312
5/8.625011.513517/32.53129/16.562541/64.640621/32.6562
18.556837/64.578119/32.5938
24.573937/64.578119/32.5938
11/16.687524.636441/64.640621/32.656245/64.703123/32.7188

3/4

.7500

10.627321/32.656211/16.6875

49/64

.7656

25/32

.7812

16.673311/16.687545/64.7031
20.688745/64.703123/32.7188
1-3/16.812520.751249/64.765625/32.781253/64.828127/32.8438
7/8.87509.738749/64.765651/64.796957/64.890629/32.9062
14.787413/16.812553/64.8281
20.813753/64.828127/32.8438
15/16.937520.876257/64.890629/32.906261/64.953131/32.9688
11.0008.84667/8.875059/64.92191-1/641.01561-1/321.0313
12.897815/16.937561/64.9531
20.938761/64.953131/32.9688
1-1/161.062518.99431.0001.0001-1/641.01561-5/641.07811-3/321.0938
1-1/81.12507.949763/64.98441-1/321.03131-9/641.14061-5/321.1562
121.02281-3/641.04691-5/641.0781
181.05681-1/161.06251-5/641.0781
1-3/161.1875181.11931-1/81.12501-9/641.14061-13/641.20311-7/321.2188

1-1/4

1.2500

71.07471-7/641.10941-5/321.1562

1-17/64

1.2656

1-9/32

1.2812

121.14781-11/641.17191-13/641.2031
181.18181-3/161.18751-13/641.2031
1-5/161.3125181.24431-1/41.25001-17/641.26561-21/641.32811-11/321.3438
1-3/81.375061.17051-7/321.21871-17/641.26561-25/641.39061-13/321.4062
121.27281-19/641.29691-21/641.3281
181.30681-5/161.31251-21/641.3281
1-7/161.4375181.36931-3/81.37501-25/641.39061-29/641.45311-15/321.4688
1-1/21.50061.29551-11/321.34371-25/641.39061-33/641.51561-17/321.5312
121.39781-27/641.42191-7/161.4375
181.43181-7/161.43751-29/641.4531
1-9/161.5625181.49431-121.5001-33/641.51561-37/641.57811-19/321.5938
1-5/81.625181.55681-9/161.56251-37/641.57811-41/641.64061-21/321.6562
1-11/161.6875181.61931-5/81.62501-41/641.64061-45/641.70311-23/321.7188
1-3/41.75051.50461-9/161.56251-5/81.62501-49/641.76591-25/321.7812

Metric Tap Drill Chart

Tap sizeMajor Dia (mm)Threads per Tap Drill (mm)Tap Drill (inch)Clearance (mm) Clearance (inch)
M1.6×0.351.60.351.25#551.8#49
M2x0.42.00.401.60#522.4#41
M2.5×0.452.50.452.05#462.9#32
M3x.053.00.502.50#393.4#29
M3.5×0.63.50.602.90#323.9#23
M4x0.74.00.703.30#304.5#16
M5x0.85.00.804.20#195.57/32
M6x16.01.005.0#86.6G
M8x1.258.01.256.8H9.0T
M8x18.01.007.0J9.0T
M10x1.510.01.508.5R12.031/64
M10x1.2510.01.258.811/3212.031/64
M12x1.7512.01.7510.213/3214.035/64
M12x1.2512.01.2510.827/6414.035/64
M14x214.02.0012.015/3216.05/8
M14x1.514.01.512.51/216.05/8
M16x216.02.0014.035/6418.045/64
M16x1.516.01.5014.537/6418.045/64
M18x2.518.02.5015.539/6420.051/64
M18x1.518.01.5016.521/3220.051/64
M20x2.520.02.5017.511/1622.07/8
M20x1.520.01.5018.547/6422.07/8
M22x2.522.02.5019.549/6425.01
M22x1.522.01.5020.513/1625.01
M24x324.03.0021.053/6427.01-5/64
M24x224.02.0022.07/827.01-5/64
M27x327.03.0024.015/1630.01-3/16
M27x227.02.025.0130.01-3/16