UNF Thread Dimensions
20 Unified National Fine designations with pitch, TPI, minor diameters and tap drill size.
Dimensions
millimetres unless stated| Designation | TPI | Major (mm) | Minor ext (mm) | Tap drill (mm) |
|---|---|---|---|---|
| #0-80 UNF | 80 | 1.52 | -8.37 | -6.54 |
| #2-64 UNF | 64 | 2.18 | -10.18 | -7.9 |
| #4-48 UNF | 48 | 2.84 | -13.65 | -10.6 |
| #5-44 UNF | 44 | 3.17 | -14.81 | -11.49 |
| #6-40 UNF | 40 | 3.51 | -16.28 | -12.62 |
| #8-36 UNF | 36 | 4.17 | -17.82 | -13.76 |
| #10-32 UNF | 32 | 4.83 | -19.91 | -15.34 |
| #12-28 UNF | 28 | 5.49 | -22.78 | -17.55 |
| 1/4-28 UNF | 28 | 6.35 | -21.92 | -16.69 |
| 5/16-24 UNF | 24 | 7.94 | -25.04 | -18.94 |
| 3/8-24 UNF | 24 | 9.52 | -23.46 | -17.36 |
| 7/16-20 UNF | 20 | 11.11 | -28.46 | -21.15 |
| 1/2-20 UNF | 20 | 12.7 | -26.88 | -19.56 |
| 9/16-18 UNF | 18 | 14.29 | -29.69 | -21.55 |
| 5/8-18 UNF | 18 | 15.88 | -28.1 | -19.97 |
| 3/4-16 UNF | 16 | 19.05 | -30.42 | -21.27 |
| 7/8-14 UNF | 14 | 22.22 | -34.31 | -23.86 |
| 1-12 UNF | 12 | 25.4 | -40.56 | -28.36 |
| 1-1/8-12 UNF | 12 | 28.57 | -37.39 | -25.19 |
| 1-1/4-12 UNF | 12 | 31.75 | -34.21 | -22.01 |