KEVOS® MAKEOS · Threads
Thread Turning Infeed per Pass
How deep should each pass be when single-point turning this thread?
Radial infeed for each pass of a single-point threading cycle with a decreasing (constant chip area) schedule, with cumulative depth and the X diameter for each pass.
Open the calculatorRuns in your browser. No account needed.
How this tool works
Inputs, units and where to find them
| Input | Unit | Typical source |
|---|---|---|
| Thread | choice | External or internal thread. |
| Nominal diameter | mm | Nominal thread diameter. |
| Pitch | mm | Thread pitch. |
| Number of passes | passes | Number of cutting passes (tool supplier tables suggest a number for each pitch). |
| Total radial depth (0 = standard) | mm | Total radial depth; 0 uses 0.6134P (external) or 0.5413P (internal), the ISO basic heights. |
Method and formulas
- First pass: Δ₁ = a_p √0.3 ÷ √(n − 1).
- Cumulative depth after pass x (x ≥ 2) = a_p √(x − 1) ÷ √(n − 1); the last pass reaches a_p.
- External X = d − 2 × depth; internal X = minor diameter + 2 × depth.
- Example: M20 × 2.5 external in 8 passes: first infeed 0.31746 mm, last 0.11375 mm.
Limitations
- Radial depth schedule only; flank or modified-flank infeed changes the X/Z moves.
- Add spring passes as your process requires.
- Example values are illustrations. Replace them with values for your actual task.
Typical uses
- Program a threading cycle by hand
- Choose the number of passes
- Check a G76 depth schedule
Who it is for
- CNC programmers
- Machinists
What you get
- Infeed for each pass
- Cumulative depth
- X diameter for each pass
Interpreting the result
- Keep the last pass above the insert’s minimum infeed (often about 0.05 mm) to avoid rubbing.
References
- Machinery’s Handbook, 29th edition (Industrial Press, 2012), printed pp. 2037–2042, 1289–1300. Topic reference; no source tables or recommended settings are reproduced.
WORKOS tools are screening and decision-support utilities. Verify important financial, engineering, safety, legal or operational decisions using appropriate professional standards and your organisation’s approved data.
