Practical tools for measured work
Bolt Circle Template Generator
Enter a bolt circle diameter and hole count to generate a full-size printable template with a calibration check.
Calculate the layout, check the diagram, then print the result for the shop or jobsite.
rotation of the first hole
0 for none
How it works
Holes are placed at equal angular intervals around the bolt circle diameter (PCD), starting from your chosen start angle. Print at 100% scale and the hole centers will be exactly the entered distances apart - center-punch through the marked crosshairs.
Worked example: six holes on a 100 mm PCD are spaced every 60 degrees, with each center 50 mm from the circle center. Changing the start angle rotates the entire pattern without changing spacing.
Before drilling
Verify the 10 mm calibration square, align the printed center with the workpiece datum, and check one opposite-hole or chord measurement with calipers. The template locates centers; it does not select drill size, tolerance or fastener clearance.
FAQ
What is PCD?
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