Thread and Drill Chart
ISO metric coarse threads from M3 to M24, with the tap drill for cutting the thread, the clearance hole for a bolt to pass through, and the spanner size.
| Thread | Pitch, mm | Tap drill, mm | Clearance hole, close, mm | Clearance hole, medium, mm | Spanner size, mm |
|---|
No sizes match. Try a thread such as M8, or a drill size such as 6.8.
Tap drills give about 75 to 80 percent thread engagement. Clearance holes follow ISO 273, and spanner sizes follow ISO 4032 hex nuts. Check your tool maker's data for hard materials or roll-form taps, which need a different drill.