1-1/4-5 ACME thread: 31.75 mm × 5 TPI
Threads › 1-1/4-5 ACME
1-1/4-5 ACME is an Acme thread: 31.75 mm major diameter, 5 TPI (5.08 mm pitch), 29° form.
| Standard | Acme |
|---|---|
| Major diameter | 31.75 mm (1.25″) |
| Pitch | 5 TPI (5.08 mm) |
| Thread angle | 29° |
| Minor diameter, bolt | 26.16 mm |
| Minor diameter, nut | 26.16 mm |
| Tap drill | Not listed. Check your tap maker's chart. |
Minor diameters worked out from the basic profile: major Ø − pitch − 0.508 mm.
Open 1-1/4-5 ACME 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.
Close in size, won't mate
- 1-1/4-7 UNCØ31.75 mm, 7 TPI
- 1-1/4-12 UNFØ31.75 mm, 12 TPI
- 1-1/4 BSWØ31.75 mm, 7 TPI
- Tr32×6Ø32 mm, 6 mm pitch
One size up or down
- 1-5 ACMEØ25.4 mm (down)
- 1-1/2-4 ACMEØ38.1 mm (up)
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.