METRICcoarse60° flank

M1.6 × 0.35 Thread Dimensions

M1.6 x 0.35 is a coarse pitch METRIC thread. Pitch is 0.35 mm, equivalent to 72.57 threads per inch. The recommended tap drill leaves roughly 75% thread engagement.

Nominal Ø1.6 mm
Pitch0.35 mm
Threads per inch72.57
Pitch Ø1.37 mm
Tap drill1.25 mm

Thread profile

millimetres unless stated
Thread profile — M1.6 x 0.35d 1.6d2 1.37d3 1.17mm60°P 0.35h3 0.21tap ⌀1.25
M1.6 × 0.35 — basic profile60° flank angle · Not to scale
Designation
M1.6 x 0.35
Thread system
METRIC
Series
coarse
Flank angle
60°
Major diameter
1.6 mm / 0.06"
Pitch
0.35 mm
Threads per inch
72.57
Pitch diameter
1.37 mm
Minor diameter (external)
1.17 mm
Minor diameter (internal)
1.22 mm
Thread depth
0.21 mm
Recommended tap drill
Ø 1.25 mm / 0.05"

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.