R1 thread: 33.25 mm × 11 TPI
Threads › R1
R1 is a BSPT taper (R / Rc) thread: 33.25 mm major diameter, 11 TPI (2.309 mm pitch), 55° form. Tap drill 30 mm. Taper thread: the Ø changes along the length, measure near the start.
| Standard | BSPT taper (R / Rc) |
|---|---|
| Major diameter | 33.249 mm (1.309″) |
| Pitch | 11 TPI (2.309 mm) |
| Thread angle | 55° |
| Tap drill | 30 mm |
Open R1 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
- G1Ø33.25 mm, 11 TPI
- 1-11.5 NPTØ33.4 mm, 11.5 TPI
- M33Ø33 mm, 3.5 mm pitch
- M33×2Ø33 mm, 2 mm pitch
One size up or down
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.