METRICcoarse60° flankISO 261

M7 × 1 Thread Dimensions

M7 x 1 is a coarse ISO Metric thread. Pitch is 1 mm, equivalent to 25.4 threads per inch. The recommended tap drill leaves roughly 75% thread engagement.

Major Ø7 mm
Pitch1 mm
Threads per inch25.4
Pitch Ø6.35 mm
Tap drill6 mm

Thread profile

millimetres unless stated
Thread profile — M7 x 1d 7d2 6.35d3 5.77mm60°P 1h3 0.613tap ⌀6
M7 × 1 — basic profile60° flank angle · Not to scale

Basic information

Designation
M7 x 1
Thread system
ISO Metric
Series
coarse
Standard
ISO 261
Basic profile
ISO 68-1 basic profile
Flank angle
60°

Dimensions

Major diameter
7 mm
Pitch
1 mm
Threads per inch
25.4
Pitch diameter
6.35 mm
Minor diameter (external)
5.77 mm
Minor diameter (internal)
5.92 mm
Thread depth
0.613 mm
Recommended tap drill
Ø 6 mm

How these values are derived

computed from the basic profile

These figures follow the ISO 68-1 basic profile of ISO 261. 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 M7 × 1 yet.

Related

Other pitches at the same 7 mm diameter — a fine pitch on a coarse diameter, or the reverse, is the usual substitution question.

Neighbouring sizes in ISO Metric.