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Bolt circle coordinates calculator
Angles are counterclockwise from positive X. Each hole appears once; the final row does not repeat the first point. Coordinates are theoretical hole centres and are not ready-to-run G-code.
Formula and inputs
Spacing = 360° / holes; X = centre X + R cos(θ); Y = centre Y + R sin(θ).
Worked example
Six holes on a 100 mm circle have 60° spacing. At a 0° start, the first centre is X50, Y0.
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.