M9×1.0 Thread Specifications
Complete dimensions for M9×1.0 fine pitch thread per ISO 724. Pitch: 1.0mm (25.4 TPI equivalent).
Thread Dimensions
| Designation | M9×1.0 |
| Thread Series | ISO Metric Fine |
| Pitch | 1.0 mm (25.4 TPI) |
| Major Diameter (d) | 9 mm (0.3543") |
| Pitch Diameter (d₂) | 8.3505 mm (0.3288") |
| Minor Diameter — External (d₁) | 7.7731 mm (0.306") |
| Minor Diameter — Internal (D₁) | 7.9175 mm (0.3117") |
| Thread Depth | 0.5413 mm |
| Tensile Stress Area | 50.14 mm² |
| Fundamental Triangle Height (H) | 0.866 mm |
Tap Drill Size
Recommended tap drill: 8.0 mm
Calculated minor diameter (D₁): 7.92 mm. Closest standard metric drill: 8.0 mm.
Closest inch drill: 5/16" (0.3125" / 7.94 mm)
Proof Loads by Property Class
| Class | Proof Stress (MPa) | Tensile Strength (MPa) | Proof Load (kN) | Tensile Load (kN) |
|---|---|---|---|---|
| 4.6 | 225 | 400 | 11.3 | 20.1 |
| 4.8 | 310 | 420 | 15.5 | 21.1 |
| 5.8 | 380 | 520 | 19.1 | 26.1 |
| 8.8 | 580 | 800 | 29.1 | 40.1 |
| 9.8 | 650 | 900 | 32.6 | 45.1 |
| 10.9 | 830 | 1040 | 41.6 | 52.1 |
| 12.9 | 970 | 1220 | 48.6 | 61.2 |
Proof load = stress area × proof stress. Per ISO 898-1.
Related Thread Sizes
Common Applications
- Automotive engine components
- Precision machinery
- Vibration-prone joints
- Cylinder head bolts
How M9×1.0 Dimensions Are Calculated
All dimensions on this page are calculated from ISO 724 formulas using the nominal diameter (9 mm) and pitch (1.0 mm):
- Fundamental triangle height: H = (√3/2) × P = 0.866 mm
- Pitch diameter: d₂ = d − 0.6495 × P = 8.3505 mm
- Minor diameter (external): d₁ = d − 1.2269 × P = 7.7731 mm
- Minor diameter (internal): D₁ = d − 1.0825 × P = 7.9175 mm
- Thread depth: 5H/8 = 0.5413 mm
- Tensile stress area: Aₛ = (π/4) × ((d₂ + d₃)/2)² = 50.14 mm²