UNFfine60° flankASME B1.1

#5-44 UNF Thread Dimensions

#5-44 UNF is a fine Unified National Fine thread. There are 44 threads per inch on a 0.1248 in major diameter, giving a metric-equivalent pitch of 0.577 mm. The recommended tap drill leaves roughly 75% thread engagement.

Major Ø0.1248 in
Threads per inch44
Pitch (metric)0.577 mm
Pitch Ø0.1102 in
Tap drill0.1024 in

Thread profile

millimetres unless stated
Thread profile — #5-44 UNFd 3.17d2 2.8d3 2.47mm60°P 0.577h3 0.354tap ⌀2.6
#5-44 UNF — basic profile60° flank angle · Not to scale

Basic information

Designation
#5-44 UNF
Series
fine
Standard
ASME B1.1
Basic profile
Unified basic profile
Flank angle
60°

Dimensions

Major diameter
0.1248 in / 3.17 mm
Pitch (metric equivalent)
0.577 mm
Threads per inch
44
Pitch diameter
0.1102 in / 2.8 mm
Minor diameter (external)
0.0972 in / 2.47 mm
Minor diameter (internal)
0.1004 in / 2.55 mm
Thread depth
0.0139 in / 0.354 mm
Recommended tap drill
Ø 0.1024 in / 2.6 mm

How these values are derived

computed from the basic profile

These figures follow the Unified basic profile of ASME B1.1. A 60° basic profile uses a fundamental triangle height H = 0.866025 × P, with external minor diameter d₃ = d − 1.226869 × P and internal minor diameter D₁ = d − 1.082532 × P; the two differ because the external root is rounded while the internal crest is truncated. A 55° Whitworth profile uses H = 0.960491 × P and a thread height of 0.640327 × P. The recommended tap drill is given as nominal diameter minus pitch, which approximates 75% thread engagement — adjust it for tough materials or deep holes.

Compatible parts0 specification pages

No specification in this database uses #5-44 UNF yet.

Related

Neighbouring sizes in Unified National Fine.