UNCcoarse60° flank
#10-24 UNC Thread Dimensions
#10-24 UNC is a coarse pitch UNC thread. There are 24 threads per inch, giving a pitch of 1.06 mm. The recommended tap drill leaves roughly 75% thread engagement.
Nominal Ø4.83 mm
Pitch1.06 mm
Threads per inch24
Pitch Ø-12.63 mm
Tap drill-22.05 mm
Thread profile
millimetres unless stated- Designation
- #10-24 UNC
- Thread system
- UNC
- Series
- coarse
- Flank angle
- 60°
- Major diameter
- 4.83 mm / 0.19"
- Pitch
- 1.06 mm
- Threads per inch
- 24
- Pitch diameter
- -12.63 mm
- Minor diameter (external)
- -28.15 mm
- Minor diameter (internal)
- -24.27 mm
- Thread depth
- 16.49 mm
- Recommended tap drill
- Ø -22.05 mm / -0.8683"
How these values are derived
Basic ISO thread geometry uses the fundamental triangle height H = 0.866025 × P. External minor diameter d₃ = d − 1.226869 × P, internal minor diameter D₁ = d − 1.082532 × P. Tap drill is given as nominal diameter minus pitch, which approximates a 75% thread engagement — adjust for tough materials or deep holes.