UNCcoarse60° flank

7/16-14 UNC Thread Dimensions

7/16-14 UNC is a coarse pitch UNC thread. There are 14 threads per inch, giving a pitch of 1.81 mm. The recommended tap drill leaves roughly 75% thread engagement.

Nominal Ø11.11 mm
Pitch1.81 mm
Threads per inch14
Pitch Ø-18.82 mm
Tap drill-34.97 mm

Thread profile

millimetres unless stated
Thread profile — 7/16-14 UNCd 11.11d2 -18.82d3 -45.43mm60°P 1.81h3 28.27tap ⌀-34.97
7/16-14 UNC — basic profile60° flank angle · Not to scale
Designation
7/16-14 UNC
Thread system
UNC
Series
coarse
Flank angle
60°
Major diameter
11.11 mm / 0.44"
Pitch
1.81 mm
Threads per inch
14
Pitch diameter
-18.82 mm
Minor diameter (external)
-45.43 mm
Minor diameter (internal)
-38.77 mm
Thread depth
28.27 mm
Recommended tap drill
Ø -34.97 mm / -1.3768"

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.