U. S. Standard Thread. Strength. Thread For Rough Iron Sizes.

Diameter Screw.

Threads per inch.

Diameter at Root of Thread.

Diameter of Tap Drill.

Tensile Strength at 5,000 lbs. per square inch.

Diameter Screw.

Threads per inch.

Diameter at Root of Thread.

Diameter of Tap Drill.

1/4

5/16

8/8 7/16

1/2

9/16

5/8

11/16

8/4

13/16

7/8

15/16

1

1 1/8

1 1/4

1 3/8

1 1/2

1 5/8

1 8/4

1 7/8

2

20 1.8

16 14

13 12 11

11

10

10

9

9

8

7

7

6

6

51/2

5

5

41/2

.185

.240

.294

.344

.400

.454

.507

.569

.620

.674

.731

.793

.837

.940

1.065

1.160

1.284

1.389

1.491

1.616

1.712

3/16

1/4

5/16

23/64

13/32 15/32

17/32

37/32

5/8

11/16 8/4 13/16

27/32

31/32 1 3/32

31/32 1 3/32 1 3/16 1 9/32

1 13/32 1 1/2 1 5/8 1 8/4

134 lbs.

226 "

339 "

465 "

625 "

809 "

1,009 "

1,271 "

1,500 "

1,780 "

2,100 "

2,470 "

2,750 "

3,400 "

3,900 "

5,300 "

6,400 "

7,650 "

8,800 "

10,150 "

11,500 "

1/4 + 1/64

5/16+1/64

3/8+1/64

7/16+1/64

1/2 + 1/64

9/16+1/32

5/8+1/64

11/16+1/32 3/4 + 1/32

13/16 + 1/32

7/8 + 1/32

15/16 + 1/32

1 + 1/32 1 1/8+ 1/32 1 1/4 + 1/32

1 3/8 + 1/32 1 1/2 + 1/32

1 5/8+1/32

1 3/4 + 1/32

1 7/8 + 1/32

2 + 1/32

20 18

16 14 13 12

11 11 10

10

9

9

8

7

7

6

6

5 1/2 5 5 41/2

.179

.

232

.282

.329

.382

.434

.483

.561

.608

.671

.714

.776

.815

.909

1.034

1.117

1.243

1.341

1.435

1.560

1.646

7/32

17/64

5/16

3/8

7/16

1/2

17/32

39/64

21/32

23/32

25/32 27/32

7/8 31/32

1 3/32

1 3/16 1 5/16 1 13/32

1 1/2 1 5/8

123/32

Proportions for Nuts.

Diameter Bolt.

Short diaraeter Hexagonal

Nut.

r Longdiameter Hexagonal Nut.

Thickness , Nut.

1/4

5/16

3/8

7/16

1/2

9/16

5/8

8/4

7/8

1

1 1/8

1 //1/4

1 3/8

1 1/2

1 5/8

1 3/4

1 7/8

2

1/2

19/32

11/16

25/32

7/8

31/32

1 1/16

1 1/4 1 7/16

1 5/8

1 13/16

2

2 3/16

2 3/8

2 9/16

2 3/4

2 15/16

3 1/8

37/64

11/16

51/64

9/10

1

1 1/8

1 7/32

1 7/16

1 21/32

1 7/8

2 3/32

2 5/16

2 17/32

2 8/4

2 31/32

3 3/16

3 13/32

35/8

1/4

5/16

3/8

7/16

1/2 9/16

5/8

8/4

7/8

1

1 1/8

1 1/4

1 3/8

1 1/2

1 5/8

1 3/4

1 7/8

2