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Bolt Circle pattern Calculator

Bolt circle hole pattern calculator
Bolt circle diameter:
Hole diameter:
Number of holes:
Start angle:
Output Unit Precision
1 2 3 4 5
Hole position data
NC format listing

Glossary

Units of measure:
The units of measure used when defining a bolt circle hole list must all be of the same type, for example: all in inches or all in millimetres.
Hole diameter:
The diameter of the holes that are equally distributed around the bolt circle diameter
Bolt circle diameter:
the diameter of the circle on which the holes will be evenly distributed.
Start angle:
The 0° angle is to the right in the "X" axis and aligned with the center of the bolt circle in the "Y" axis. The angle is described as...
- A positive angle is counterclockwise
- A negative angle is clockwise. ex:-45° = 315°
Angle units
360° = 21,600 minutes = 1,296,000 seconds = 6.2832 radians = full circle
(1 degree) = 60 minutes = 3,600 seconds = 0.0175 radian
0°1' (1 minute of a degree) = .016 degree = 60 seconds = .000298 radian
0°0'1" (1 second of a degree) = .00027 degree = .0000048 radian
Angle entry field (Convert decimal angle to; degrees, minutes and seconds)
Angle format example 1: decimal 15.5° enter as 15.5 no formating needed.
Angle format example 2: 64°45'34" enter as 64d45m34s
Angle format example 3: -30°5' enter as -30d5m
Angle format example 4: 15°0'10" enter as 15d10s
Angle format example 5: -0°0'50" enter as -50s

Last Updated: 27 February 2012 HTML5 Powered Graphics

Decimal Degree
Sexagesimal Degree
Fraction Convert
Fraction inch mm
1/256 .0039
0.10
1/128
.0078 0.20
1/64
.0156 0.40
1/32 .0313
0.79
3/64 .0469
1.19
1/16
.0625 1.59
3/32 .0938
2.38
7/64 .1094
2.78
1/8
.1250 3.18
9/64
.1406 3.57
5/32 .1563
3.97
11/64 .1719
4.37
3/16 .1875
4.76
13/64 .2031
5.16
7/32 .2188
5.56
15/64
.2344 5.95
1/4
.2500 6.35
5/16 .3125
7.94
21/64 .3281
8.33
11/32
.3438 8.73
23/64
.3594 9.13
25/64 .3906
9.92
13/32 .4063
10.32
27/64
.4219 10.72
7/16
.4375 11.11
29/64 .4531
11.51
15/32 .4688
11.91
31/64
.4844 12.30
1/2
.5000 12.70
33/64 .5156
13.10
17/32 .5313
13.49
35/64
.5469 13.89
9/16
.5625 14.29
37/64 .5781
14.68
19/32 .5938
15.08
39/64
.6094 15.48
5/8
.6250 15.88
41/64 .6406
16.27
21/32 .6563
16.67
43/64
.6719 17.07
11/16
.6875 17.46
45/64 .7031
17.86
23/32 .7188
18.26
47/64
.7344 18.65
3/4
.7500 19.05
49/64 .7656
19.45
25/32 .7813
19.84
51/64
.7969 20.24
13/16 .8125 20.64
53/64
.8281 21.03
27/32 .8438
21.43
55/64 .8594
21.83
7/8
.8750 22.23
57/64
.8906 22.62
29/32
.9063 23.02
59/64
.9219 23.42
15/16 .9375
23.81
61/64 .9531
24.21
61/64
.9531 24.21
31/32
.9688 24.61
63/64 .9844
25.00
1 1.0000
25.40

18 August 2011

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