Acme General Purpose 2G Thread Series Limiting Dimensions & Tolerances

The dimensions listed below can be used to determine the diameter along with the thread pitch. For further clarification of thread per inch, please download our gauge guide.

External Thread Dimensions

Major Dia.Pitch Dia.Minor Dia.
Designation Size DecimalTPITol. ClassMaxMinMaxMinMax Min
3/8-12 Acme0.375
12
2G
0.375
0.37
0.3284
0.3161
0.2817
0.2632
1/2-10 Acme0.5
102G
0.5
0.495
0.4443
0.4306
0.38
0.3594
5/8- 4 Acme0.625
42G STUB0.625
0.619
0.5421
0.524
0.455
0.4327
5/8-6 Acme0.625
62G
0.625
0.6167
0.5348
0.5174
0.4383
0.4128
5/8-8 Acme0.625
82G
0.625
0.6188
0.5562
0.5408
0.48
0.457
5/8- 10 Acme0.625
102G
0.625
0.62
0.5693
0.5556
0.505
0.4844
3/4-5 Acme0.75
52G
0.75
0.74
0.642
0.6226
0.53
0.5009
3/4-6 Acme0.75
62G
0.75
0.7417
0.6598
0.6424
0.5633
0.5371
3/4-8 Acme0.75
82G
0.75
0.7438
0.6812
0.6658
0.605
0.582
3/4-10 Acme0.75
102G
0.75
0.745
0.6931
0.6784
0.63
0.608
7/8-5 Acme0.875
52G
0.8750.865
0.767
0.7476
0.655
0.6259
7/8-6 Acme0.875
62G
0.8750.8667
0.7842
0.7663
0.6883
0.6615
7/8-8 Acme0.875
72G
0.8750.8688
0.8062
0.7908
0.73
0.707
1-4 Acme0.875
42G
10.9875
0.8652
0.8429
0.73
0.6965
1-5 Acme1
52G
10.99
0.892
0.8726
0.78
0.7509
1-6 Acme1
62G
10.9917
0.9098
0.8929
0.8133
0.7871
1-8 Acme1
82G
10.9938
0.9312
0.9158
0.855
0.832
1-10Acme1
102G
10.995
0.942
0.9264
0.88
0.8568
1 1/8-4 Acme1.125
42G
1.1251.1125
0.9902
0.9679
0.855
0.8219
1 1/8-5 Acme1.125
52G
1.1251.115
1.0165
0.9967
0.905
0.8753
1 1/8-6 Acme1.125
62G
1.1251.1167
1.0312
1.0163
0.9383
0.9115
1 1/4-4 Acme1.25
42G
1.25
1.2375
1.1152
1.0929
0.98
0.9465
1 1/4-5 Acme1.25
52G
1.25
1.24
1.1411
1.121
1.03
0.9998
1 1/4-6 Acme1.25
62G
1.25
1.2417
1.1598
1.1424
1.0633
1.0371
1 1/4-8 Acme1.25
82G
1.25
1.2437
1.1786
1.1612
1.105
1.079
1 3/8-4 Acme1.375
42G
1.375
1.3625
1.2406
1.2186
1.105
1.0719
1 3/8-5 Acme1.375
52G
1.3751.365
1.2661
1.2461
1.155
1.124
1 3/8-6 Acme1.375
62G
1.3751.3667
1.2848
1.2674
1.1883
1.1621
1 1/2-4 Acme1.5
42G
1.51.4875
1.3652
1.3429
1.23
1.1965
1 1/2-5 Acme1.5
52G
1.51.49
1.392
1.3726
1.28
1.2209
1 1/2-6Acme1.5
62G
1.51.4834
1.4098
1.3924
1.3133
1.2871
1 3/4-4 Acme1.75
42G
1.751.7375
1.6145
1.5916
1.48
1.4456
1 3/4-5 Acme1.75
52G
1.751.74
1.642
1.6226
1.53
1.5009
1 3/4-6 Acme1.75
62G
1.751.7417
1.6561
1.6359
1.5633
1.5331
2-4 Acme2
42G
21.9875
1.8637
1.8402
1.73
1.6948
2 1/4 - 4 Acme2.25

42G
2.252.2375
2.1137
2.0902
1.98
1.9448
2 1/2 -4 Acme2.5

42G
2.52.4875
2.3637
2.3402
2.23
2.1948

 

Internal Thread Dimensions

Major Dia.Pitch Dia. Minor Dia.
Designation Size DecimalTPITol. ClassMaxMinMaxMinMax Min
3/8-12 Acme0.375
12
2G
0.375
0.385
0.3457
0.3333

0.2967


0.2917
1/2-10 Acme0.5
102G
0.54

0.52
0.4637
0.45
0.405
0.4
5/8- 4 Acme0.625
42G STUB0.6647

0.645
0.5697
0.55
0.4875
0.475
5/8-6 Acme0.625
62G
0.665

0.645

0.5587

0.5417
0.4667
0.4583
5/8-8 Acme0.625
82G
0.665

0.645

0.5779

0.5625
0.5062
0.5
3/4-5 Acme0.75
52G
0.79
0.77

0.6686
0.65
0.56

0.55
3/4-6 Acme0.75
62G
0.79
0.77

0.6841
0.6667
0.5717

0.5833
3/4-8 Acme0.75
82G
0.79

0.77

0.7033

0.6875
0.6312
0.625
3/4-10 Acme0.75
102G
0.79

0.77
0.71470.7

0.655

0.65
7/8-5 Acme0.875
52G
0.9150.895
0.794


0.775
0.685

0.675
7/8-6 Acme0.875
62G
0.915
0.895
0.8095

0.7917
0.7167
0.7083
7/8-8 Acme0.875
82G
0.915
0.895
0.8287
0.8125
0.7562
0.75
1-4 Acme0.875
42G
1.04

1.02
0.896

0.875
0.7625
0.75
1-5 Acme1
52G
1.041.02

0.91940.9
0.81
0.8
1-6 Acme1
62G
1.041.02

0.9349
0.9167
0.8417
0.8333
1-8 Acme1
82G
1.041.02
0.9541
0.9375
0.8812


0.875
1-10 Acme1
102G
1.041.02
0.9655

0.95

0.905

0.9
1 1/8-4 Acme1.125
42G
1.165
1.145
1.0214
1
0.8875

0.875
1 1/8-5 Acme1.125
52G
1.165
1.145

1.04881.025

0.935

0.925
1 1/8-6 Acme1.125
62G
1.165
1.145
1.0603


1.0417
0.09667

0.9583
1 1/4-4 Acme1.25
42G
1.29

1.27
1.1467
1.125
1.0125
1
1 1/4-5 Acme1.25
52G
1.29

1.27
1.17011.15

1.06

1.05
1 1/4-6 Acme1.25
62G
1.29

1.27
1.1856
1.1667
1.0917

1.0833
1 3/8-4 Acme1.375
42G
1.415

1.395
1.2721.25
1.375

1.125
1 3/8-5 Acme1.375
52G
1.415
1.3951.2955

1.275
1.185

1.175
1 3/8-6 Acme1.375
62G
1.415
1.3951.3109

1.29171.2167


1.2083
1 1/2-4 Acme1.5
42G
1.54
1.52
1.3973
1.375

1.2625
1.25
1 1/2-5 Acme1.5
52G
1.54
1.52
1.42081.4

1.31
1.3
1 1/2-6Acme1.5
62G
1.54
1.52
1.43631.4167

1.3417
1.333
1 3/4-4 Acme1.75
42G
1.79
1.77
1.64791.625
1.5125

1.5
1 3/4-5 Acme1.75
52G
1.79
1.77
1.67141.65
1.56
1.55
1 3/4-6 Acme1.75
62G
1.79
1.77
1.6869
1.6667

1.5917
1.5833
2-4 Acme2
42G
2.04
2.02
1.8985

1.875
1.7625

1.75
2 1/4 - 4 Acme2.25

42G
2.2906
2.27

2.1492.0125

2.125

2
2 1/2 -4 Acme2.5

42G
2.54
2.52
2.39952.375
2.2625

2.25