1-1/8-7 UNC Thread Specifications
Complete dimensions for 1-1/8-7 UNC (Unified National Coarse) thread per ASME B1.1. TPI: 7, Pitch: 0.14286" (3.629 mm).
Thread Dimensions
| Designation | 1-1/8-7 UNC |
| Threads Per Inch (TPI) | 7 |
| Pitch | 0.14286" (3.629 mm) |
| Major Diameter | 1.125" (28.575 mm) |
| Pitch Diameter | 1.0322" (26.218 mm) |
| Minor Diameter (External) | 0.9497" (24.123 mm) |
| Minor Diameter (Internal) | 0.9704" (24.647 mm) |
| Thread Depth | 0.07732" (1.964 mm) |
| Tensile Stress Area | 0.76328 in² (492.4 mm²) |
Tap Drill Size
Recommended tap drill: 31/32" (0.9688" / 24.61 mm)
Calculated minor diameter (internal): 0.9704" (24.65 mm)
Proof Loads by SAE Grade
| Grade | Proof Stress (psi) | Tensile Strength (psi) | Proof Load (lbf) | Tensile Load (lbf) |
|---|---|---|---|---|
| Grade 2 | 55,000 | 74,000 | 41,980 | 56,483 |
| Grade 5 | 85,000 | 120,000 | 64,879 | 91,594 |
| Grade 8 | 120,000 | 150,000 | 91,594 | 114,492 |
Same Size, Different Series
Common Applications
- Heavy structural, foundation bolts, large machinery
- Coarse thread applications