1-3/8-6 UNC thread: 34.92 mm × 6 TPI
Threads › 1-3/8-6 UNC
1-3/8-6 UNC is a UNC thread: 34.92 mm major diameter, 6 TPI (4.233 mm pitch), 60° form.
| Standard | UNC |
|---|---|
| Major diameter | 34.925 mm (1.375″) |
| Pitch | 6 TPI (4.233 mm) |
| Thread angle | 60° |
| Minor diameter, bolt | 29.73 mm |
| Minor diameter, nut | 30.34 mm |
| Tap drill | Not listed. Check your tap maker's chart. |
| Usual class | 2A bolt, 2B nut |
Minor diameters worked out from the basic profile: major Ø − 1.22687 × pitch (bolt) and − 1.08253 × pitch (nut).
Open 1-3/8-6 UNC in BenchsmithAdd to order list
Measure it
Bolt: Measure across the crests of the bolt with the caliper jaws. Worn bolts read 0.1 to 0.3 under.
Nut or tapped hole: Measure across the tops of the threads inside the nut or hole with the inside jaws. That is the minor Ø. Worn or oversize holes read a little over.
One size up or down
- 1-1/4-7 UNCØ31.75 mm (down)
- 1-1/2-6 UNCØ38.1 mm (up)
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.