Machining
Bolt circle
In short
X/Y coordinates of n holes on a circle or arc, hole spacing, full-size marking template and DXF. Example with the default values: Angular pitch = 60°.
Calculation
Example calculated with the tool’s default values.
Inputs
- Layout
- Full circle, equal pitch
- Bolt circle Ø
- 150 mm
- Number of holes
- 6
- First hole angle
- 0°
- Direction
- Counter-clockwise
- Centre X
- 0 mm
- Centre Y
- 0 mm
- Hole Ø
- 18 mm
Results
- Angular pitch
- 60°
- Distance between adjacent holes
- 75.000 mm
Worked example
Every value in this section belongs to the example, calculated with the tool’s default values.
Other results of the example
- Hole 1: X
- 75.000 mm
- Hole 1: Y
- 0.000 mm
- Web between holes
- 57.00 mm
- Opposite holes distance
- 150.000 mm
Step-by-step calculation
Angular pitch
pitch = 360° / n
360 / 6 = 60.000°
Coordinates
X = X0 + R cos θ ; Y = Y0 + R sin θ
R = 75.000 mm
Adjacent distance
c = D · sin(pitch / 2)
150.00 × sin 30.000° = 75.000 mm
Hole coordinates
| Hole | Angle (°) | X (mm) | Y (mm) |
|---|---|---|---|
| 1 | 0.000 | 75.000 | 0.000 |
| 2 | 60.000 | 37.500 | 64.952 |
| 3 | 120.000 | −37.500 | 64.952 |
| 4 | 180.000 | −75.000 | 0.000 |
| 5 | 240.000 | −37.500 | −64.952 |
| 6 | 300.000 | 37.500 | −64.952 |
Limits
Indicative results: they replace neither the applicable standards nor the job drawings and instructions. Check the values entered and the result before doing the work.
Sources
- Géométrie : Calcul direct (trigonométrie)
- Coordonnées polaires → cartésiennes : X = R cos θ, Y = R sin θ ; corde = 2 R sin(Δθ/2)
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