1. What is 100° Countersink Depth?

The 100° countersink depth calculation determines how deep to drill a conical hole so that a screw head sits flush with the material surface. The 100° refers to the included angle of the countersink.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{dia} \) — Desired countersink diameter (inches)
• \( \text{screw\_dia} \) — Screw head diameter (inches)
• \( 50° \) — Half of the countersink angle (100° total)

Explanation: The formula calculates the vertical depth needed to achieve the specified countersink diameter based on the 100° angle.

3. Importance of Countersink Depth

Details: Proper countersink depth ensures screw heads sit flush with the material surface, preventing protrusions that could interfere with other components or create safety hazards.

4. Using the Calculator

Tips: Enter both diameters in inches. The hole diameter must be larger than the screw diameter. Measurements should be precise for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: Why 100° countersink angle?
A: 100° is a common standard for many screw types, providing a good balance between head strength and flush seating.

Q2: What if I need a different angle?
A: The formula can be adapted by changing the angle value (use half the included angle in the tangent function).

Q3: How precise should measurements be?
A: For best results, measure to at least 0.001 inches (thousandths) precision, especially for small screws.

Q4: Does material affect the calculation?
A: The calculation is purely geometric, but softer materials may require slightly different depths due to compression.

Q5: Can this be used for metric measurements?
A: Yes, as long as both diameters are in the same units (mm or inches), the result will be in those units.