Tap Drill Size for M24x2.0

Thread Specifications for M24x2.0

Here are the complete specifications for the M24x2.0 thread:

• Major Diameter: 24.0mm (0.9449″)
• Pitch: 2.0mm
• Tap Drill Size: 22.0mm (0.8661″ / 22.0mm)
• Thread Engagement: ~75% (standard)

How Is the Tap Drill Size Calculated?

The tap drill size for metric threads is calculated using this simple formula:

Tap Drill Diameter = Major Diameter – Pitch

For M24x2.0:

Tap Drill = 24.0mm – 2.0mm = 22.0mm

The recommended tap drill is 22.0mm, which gives approximately 75% thread engagement — the industry standard for most applications.

Why 75% Thread Engagement?

Thread engagement percentage determines how deep the threads are cut. While more might seem better, there is a practical limit:

• 50% engagement provides about 90% of full thread strength — ideal for softer materials or when tap breakage is a concern.
• 75% engagement is the industry standard — excellent strength with reasonable tapping effort. This is what the 22.0mm drill provides for M24x2.0.
• Beyond 83% adds almost no additional strength but significantly increases tapping torque and tap breakage risk.

Pro tip: In aluminum, brass, or other soft materials, 50-60% thread engagement is often preferred to reduce tap breakage. Save 75%+ for steel and harder materials.

Related Thread Sizes

• Tap Drill for M24x1.0 — 23.0mm (0.9055″)
• Tap Drill for M24x1.5 — 22.5mm (0.8858″)
• Tap Drill for M27x1.0 — 26.0mm (1.0236″)
• Tap Drill for M27x1.5 — 25.5mm (1.0039″)