Theoretical thread dimensions
Single-start 60° profile. Approximate basic values without tolerance-class allowances; these are not acceptance limits or tap-drill diameters.
- Basic pitch diameter
- 5.3505 mm
- Approx. external minor Ø
- 4.7731 mm
- Triangle height H
- 0.866 mm
01What M6 × 1 means
M identifies the metric 60° thread family. The 6 is nominal diameter; the 1 is pitch. A coarse-series M6 designation may omit pitch, but checking it is sensible when working on an existing part.
02Why a 5 mm drill is used
The consulted cutting-tap recommendation is 5 mm. Subtracting 1 from 6 matches this practical reference, but does not establish a universal rule for every method, material or thread engagement percentage.
03Preventing blind-hole tap breakage
Separate useful thread depth from drilled depth. The tap needs room for its chamfer and chips. Choose flute form and lubrication for the material and hole type, and check bottom clearance before extending the threaded length.
Similar threads: check diameter and pitch
A fine-pitch M6 keeps the nominal diameter but changes the pitch, drill and fit. Check the full drawing designation.
| Thread | Ø mm | Pitch |
|---|---|---|
| M6 × 1 | 6 | 1 mm |
| M6 × 0.75 | 6 | 0.75 mm |
Frequently asked questions · M6 × 1
Which drill is used for M6 × 1?
The consulted cutting-tap reference specifies 5 mm. Form tapping requires a separately checked hole size.
What is the pitch of M6 × 1?
Pitch is 1 mm. For a single-start thread this is also the axial travel per revolution.
Does the drill size determine finished tolerance?
No. The drill prepares the hole; the tool, process and specified tolerance class determine the fit to be inspected.
Sources and standard reference
Cutting-tap drill:
VÖLKEL · Metric cutting tapsISO 68-1 · Metric thread profile
Nominal reference data. The drawing, tolerance class and tool instructions govern hole preparation and acceptance. Do not automatically use a cutting-tap drill size for form tapping.
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