Dimension

The dimension describes the geometric specifications of a tool or component – e.g. length, diameter or thread depth. When tapping threads, precise dimensions are crucial:

Only correctly sized tools guarantee a clean and accurate thread.
Deviations can lead to assembly problems or damage.

Practical example: An M8 tap (metric ISO thread, coarse thread) requires a core hole with the correct diameter (e.g. approximately 6.8 mm). If the dimension is incorrect, the screw will not be able to be threaded in later.

Calculation – The rule of thumb is:

Core hole diameter ≈ nominal diameter – pitch

For M8 × 1.25 (coarse thread):
8.0 mm – 1.25 mm = 6.75 mm → rounded to 6.8 mm
For M8 × 1.0 (fine thread):
8.0 mm – 1.0 mm = 7.0 mm
For M8 × 0.75 (fine thread, less common):
8.0 mm – 0.75 mm = 7.25 mm

Taps & Dies

BaerCoil/BaerFix

Drill chucks

Twist drill bits

Screw taps and thread cutting dies convince with BAER quality

BaerCoil & BaerFix thread inserts for thread repair and thread reinforcement

Drill chucks

Twist drill bit - First-class quality from a professional

Dimension

Screw taps and thread cutting dies convince with BAER quality

BaerCoil & BaerFix thread inserts for thread repair and thread reinforcement

Drill chucks

Twist drill bit - First-class quality from a professional

Dimension

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