M14×1.5 Thread Specifications
Complete dimensions for M14×1.5 fine pitch thread per ISO 724. Pitch: 1.5mm (16.9 TPI equivalent).
Thread Dimensions
| Designation | M14×1.5 |
| Thread Series | ISO Metric Fine |
| Pitch | 1.5 mm (16.9 TPI) |
| Major Diameter (d) | 14 mm (0.5512") |
| Pitch Diameter (d₂) | 13.0258 mm (0.5128") |
| Minor Diameter — External (d₁) | 12.1596 mm (0.4787") |
| Minor Diameter — Internal (D₁) | 12.3763 mm (0.4873") |
| Thread Depth | 0.8119 mm |
| Tensile Stress Area | 124.55 mm² |
| Fundamental Triangle Height (H) | 1.299 mm |
Tap Drill Size
Recommended tap drill: 12.5 mm
Calculated minor diameter (D₁): 12.38 mm. Closest standard metric drill: 12.5 mm.
Closest inch drill: 31/64" (0.4844" / 12.3 mm)
Proof Loads by Property Class
| Class | Proof Stress (MPa) | Tensile Strength (MPa) | Proof Load (kN) | Tensile Load (kN) |
|---|---|---|---|---|
| 4.6 | 225 | 400 | 28.0 | 49.8 |
| 4.8 | 310 | 420 | 38.6 | 52.3 |
| 5.8 | 380 | 520 | 47.3 | 64.8 |
| 8.8 | 580 | 800 | 72.2 | 99.6 |
| 9.8 | 650 | 900 | 81.0 | 112.1 |
| 10.9 | 830 | 1040 | 103.4 | 129.5 |
| 12.9 | 970 | 1220 | 120.8 | 152.0 |
Proof load = stress area × proof stress. Per ISO 898-1.
Related Thread Sizes
Common Applications
- Connecting rods
- Suspension components
- High-strength assemblies
- Precision equipment
How M14×1.5 Dimensions Are Calculated
All dimensions on this page are calculated from ISO 724 formulas using the nominal diameter (14 mm) and pitch (1.5 mm):
- Fundamental triangle height: H = (√3/2) × P = 1.299 mm
- Pitch diameter: d₂ = d − 0.6495 × P = 13.0258 mm
- Minor diameter (external): d₁ = d − 1.2269 × P = 12.1596 mm
- Minor diameter (internal): D₁ = d − 1.0825 × P = 12.3763 mm
- Thread depth: 5H/8 = 0.8119 mm
- Tensile stress area: Aₛ = (π/4) × ((d₂ + d₃)/2)² = 124.55 mm²