Bolt Sizes
(SHCS)
 

A
Size
B
Drill Size
C
Pilot
D
C'Bore
E
Cap
F
Height
G
Hex
Inch
 
6
10
1/4
5/16
3/8

1/2
5/8
3/4
7/8
1

0.138
0.190
0.250
0.313
0.375

0.500
0.625
0.750
0.875
1.000

UNC
-32
-24
-20
-18
-16

-13
-11
-10
-9
-8

#36
#25
#7
F
5/16

27/64
35/64
21/32
49/64
7/8

0.107
0.150
0.201
0.257
0.313

0.422
0.547
0.656
0.766
0.875

UNF
-40
-32
-28
-24
-24

-20
-18
-16
-14
-12

#33
#21
#3
I
Q

29/64
37/64
11/16
13/16
59/64

0.113
0.159
0.213
0.272
0.332

0.453
0.578
0.688
0.813
0.922

 
#18
#2
9/32
11/32
13/32

17/32
21/32
25/32
29/32
1-1/32

0.170
0.221
0.281
0.344
0.406

0.531
0.656
0.781
0.906
1.031

 
9/32
3/8
7/16
17/32
5/8

13/16
1
1-3/16
1-3/8
1-5/8

0.281
0.375
0.438
0.531
0.625

0.813
1.000
1.188
1.375
1.625

 
0.226
0.313
0.375
0.469
0.563

0.750
0.938
1.125
1.313
1.500

 
0.138
0.190
0.250
0.313
0.375

0.500
0.625
0.750
0.875
1.000

 
7/64
5/32
3/16
1/4
5/16

3/8
1/2
5/8
3/4
3/4

Metric
M5
M6
M8
M10
M12

M14
M16
M20
M24

0.197
0.236
0.315
0.394
0.472

0.551
0.630
0.787
0.945

-1.0
-1.25
-1.5
-1.75
-2.0

-2.0
-2.5
-2.5
-3.0

4.20
5.00
6.75
8.50
10.25

12.00
14.00
17.50
21.00

5.80
6.80
8.80
10.80
12.80

14.75
16.75
20.75
24.75

9.75
11.25
14.25
17.25
19.25

22.25
25.50
31.50
37.50

8.5
10
13
16
18

21
24
30
36

5
6
8
10
12

14
16
20
24

4
5
6
8
10

12
14
17
19


Values recommended by Unbrako.

Home Copyright © 1999-2010 Parker Mundy.
All rights reserved.