3/8-12 ACME thread: 9.52 mm × 12 TPI
Threads › 3/8-12 ACME
3/8-12 ACME is an Acme thread: 9.52 mm major diameter, 12 TPI (2.117 mm pitch), 29° form.
| Standard | Acme |
|---|---|
| Major diameter | 9.525 mm (0.375″) |
| Pitch | 12 TPI (2.117 mm) |
| Thread angle | 29° |
| Minor diameter, bolt | 6.9 mm |
| Minor diameter, nut | 6.9 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 3/8-12 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
- 3/8-16 UNCØ9.52 mm, 16 TPI
- 3/8-24 UNFØ9.52 mm, 24 TPI
- 3/8 BSWØ9.52 mm, 16 TPI
- G1/8Ø9.73 mm, 28 TPI
- R1/8Ø9.73 mm, 28 TPI
- M10Ø10 mm, 1.5 mm pitch
One size up or down
- 5/16-14 ACMEØ7.94 mm (down)
- 7/16-12 ACMEØ11.11 mm (up)
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.