x

Resources

Standard Pitch Diameter Chart - Inch

Thread Ring Gages

 

 

NOMINAL SIZE

UNIFIED PITCH DIAMETER

CLASS 2A

CLASS 3A

X TOL. GO = – NO GO

= +

GO

NOT GO

GO

NOT GO

#0-80 UNF

.0514

.0496

.0519

.0506

.0002

#1-64 UNC

.0623

.0603

.0629

.0614

.0002

#1-72 UNF

.0634

.0615

.0640

.0626

.0002

#2-56 UNC

.0738

.0717

.0744

.0728

.0002

#2-64 UNF

.0753

.0733

.0759

.0744

.0002

#3-48 UNC

.0848

.0825

.0855

.0838

.0002

#3-56 UNF

.0867

.0845

.0874

.0858

.0002

#4-40 UNC

.0950

.0925

.0958

.0939

.0002

#4-48 UNF

.0978

.0954

.0985

.0967

.0002

#5-40 UNC

.1080

.1054

.1088

.1069

.0002

#5-44 UNF

.1095

.1070

.1102

.1083

.0002

#6-32 UNC

.1169

.1141

.1177

.1156

.0003

#6-40 UNF

.1210

.1184

.1218

.1198

.0002

#8-32 UNC

.1428

.1399

.1437

.1415

.0003

#8-36 UNF

.1452

.1424

.1460

.1439

.0002

#10-24 UNC

.1619

.1586

.1629

.1604

.0003

#10-32 UNF

.1688

.1658

.1697

.1674

.0003

#12-24 UNC

.1879

.1845

.1889

.1863

.0003

#12-28 UNF

.1918

.1886

.1928

.1904

.0003

#12-32 UNEF

.1948

.1917

.1957

.1933

.0003

1/4  - 20 UNC

.2164

.2127

.2175

.2147

.0003

1/4  - 28 UNF

.2258

.2225

.2268

.2243

.0003

1/4  - 32 UNEF

.2287

.2255

.2297

.2273

.0003

5/16  - 18 UNC

.2752

.2712

.2764

.2734

.0003

5/16 - 24 UNF

.2843

.2806

.2854

.2827

.0003

5/16 - 32 UNEF

.2912

.2880

.2922

.2898

.0003

3/8  - 16 UNC

.3331

.3287

.3344

.3311

.0003

3/8  - 24 UNF

.3468

.3430

.3479

.3450

.0003

3/8  - 32 UNEF

.3537

.3503

.3547

.3522

.0003

7/16  - 14 UNC

.3897

.3850

.3911

.3876

.0003

7/16 - 20 UNF

.4037

.3995

.4050

.4019

.0003

7/16 - 28 UNEF

.4132

.4096

.4143

.4116

.0003

1/2  - 13 UNC

.4485

.4435

.4500

.4463

.0003

1/2  - 20 UNF

.4662

.4619

.4675

.4643

.0003

1/2  - 28 UNEF

.4757

.4720

.4768

.4740

.0003

9/16  - 12 UNC

.5068

.5016

.5084

.5045

.0003

9/16 - 18 UNF

.5250

.5205

.5264

.5230

.0003

9/16 - 24 UNEF

.5342

.5303

.5354

.5325

.0003

5/8  - 11 UNC

.5644

.5589

.5660

.5619

.0003

5/8  - 18 UNF

.5875

.5828

.5889

.5854

.0003

5/8 - 24 UNEF

.5967

.5927

.5979

.5949

.0003

11/16 - 24 UNEF

.6592

.6552

.6604

.6574

.0003

3/4  - 10 UNC

.6832

.6773

.6850

.6806

.0003

3/4  - 16 UNF

.7079

.7029

.7094

.7056

.0003

3/4 - 20 UNEF

.7162

.7118

.7175

.7142

.0003

13/16 - 20 UNEF

.7787

.7743

.7800

.7767

.0003

7/8  - 9 UNC

.8009

.7946

.8028

.7981

.0003

7/8  - 14 UNF

.8270

.8216

.8286

.8245

.0003

7/8 - 20 UNEF

.8412

.8368

.8425

.8392

.0003

15/16 - 20 UNEF

.9036

.8991

.9050

.9016

.0003

1”-8 UNC

.9168

.9100

.9188

.9137

.0004

1”-12 UNF

.9441

.9382

.9459

.9415

.0003

1”-14 UNS

.9519

.9463

.9536

.9494

.0003

1”-20 UNEF

.9661

.9616

.9675

.9641

.0003

1 1/16 - 12 UN

1.0067

1.0010

1.0084

1.0042

.0003

1 1/16 - 18 UNEF

1.0250

1.0203

1.0264

1.0228

.0003

1 1/8  - 7 UNC

1.0300

1.0228

1.0322

1.0268

.0004

1 1/8  - 12 UNF

1.0691

1.0631

1.0709

1.0664

.0003

1 1/8  - 18 UNEF

1.0875

1.0828

1.0889

1.0853

.0003

1 3/16 - 12 UN

1.1317

1.1259

1.1334

1.1291

.0003

1 3/16 - 18 UNEF

1.1499

1.1450

1.1514

1.1478

.0003

1 1/4  - 7 UNC

1.1550

1.1476

1.1572

1.1517

.0004

1 1/4  - 12 UNF

1.1941

1.1879

1.1959

1.1913

.0003

1 1/4  - 18 UNEF

1.2124

1.2075

1.2139

1.2103

.0003

1 5/16 - 12 UN

1.2567

1.2509

1.2584

1.2541

.0003

1 5/16 - 18 UNEF

1.2749

1.2700

1.2764

1.2728

.0003

1 3/8  - 6 UNC

1.2643

1.2563

1.2667

1.2607

.0004

1 3/8  - 12 UNF

1.3190

1.3127

1.3209

1.3162

.0003

1 3/8  - 18 UNEF

1.3374

1.3325

1.3389

1.3353

.0003

1 7/16 - 12 UN

1.3816

1.3757

1.3834

1.3790

.0003

1 7/16 - 18 UNEF

1.3999

1.3949

1.4014

1.3977

.0003

1 1/2  - 6 UNC

1.3893

1.3812

1.3917

1.3856

.0004

1 1/2  - 12 UNF

1.4440

1.4376

1.4459

1.4411

.0003

1 1/2  - 18 UNEF

1.4624

1.4574

1.4639

1.4602

.0003

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