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Partial bolt circle coordinates calculator
A positive sweep proceeds counterclockwise; a negative sweep proceeds clockwise. Use a full bolt circle tool when you do not want a repeated endpoint at 360°. Confirm the origin and start angle against your drawing.
Formula and inputs
Spacing = sweep / (holes − 1); both arc endpoints are included.
Worked example
Five holes through 180° have 45° spacing, with holes at 0°, 45°, 90°, 135° and 180°.
Use the result in your setup
Confirm the input dimensions and unit system against your drawing before calculating. Keep full precision during a calculation and round only the final value to suit the measurement or programming requirement. A numerical result does not account for a machine’s complete setup, workholding or control configuration.