Size

Length,
inches

Number
in a
pound

Safe Lateral Load*

Resistance to withdrawal
in pounds per inch of penetration 
perpendicular to the grain,
into the main member,
in Douglas Fir

Required
penetration.
inches

load,
pounds,
in Douglas Fir

2d           

1               

15             

876       

3d

1¼ 

14

568

4d

1½

12½

316

5d

1¾

12½

271

6d

2

11½

181

1

70

27

7d

2¼

11½

161

8d

2½

10¼

106

1¼

100

32

9d

2¾

10½

96

32

10d

3

9

69

1½

120

36

12d

3¼

9

64

1 5/8

130

36

16d

3½

8

49

1 5/8

160

40

20d

4 

6

31

2

190

48

30d

4½ 

5

24

2¼

230

52

40d

5

4

18

2 1/3

270

56

50d

5½

3

14

2¾

310

61

60d

6

2

11

3

360

67