How to Use This Calculator
- Enter the screw diameter (the nominal size of your screw)
- Set the countersink angle (typically 82° for standard countersinks or 90° for flat-bottomed countersinks)
- Input the material thickness where the screw will be installed
- Click the Calculate button to determine the recommended countersink diameter
Understanding the Formula
The calculator uses the following formula to determine the countersink diameter:
D = d × (2 × tan(θ/2) + 1)
Where:
- D = Countersink Diameter
- d = Screw Diameter
- θ = Countersink Angle
When to Use This Calculator
This calculator is particularly useful in:
- Woodworking projects requiring proper screw installation
- Manufacturing processes where clean, professional-looking joints are essential
- Automotive repairs and assembly
- DIY projects where appearance and structural integrity are both important
Important Considerations
While this calculator provides a good starting point, keep in mind:
- The actual countersink diameter may need to be adjusted based on material type and screw type
- For self-tapping screws, a slightly larger countersink may be needed
- Always verify your calculations with manufacturer specifications for specialized applications