Professional CNC Machining Calculator
A real engineering calculator — every number on this page is computed live by a tested calculation engine, never hardcoded. Start with the Milling or HEM module, or load the Aluminum 6061-T6 educational demonstration.
Milling Calculator
Results User-Supplied Data Theoretical Calculation
HEM / Adaptive Milling
Enter a programmed fz above to see the feed, MRR, power and the actual chip thickness your entered setting really produces.
Results User-Supplied Data Theoretical Calculation
Target — required to hold the target chip thickness
Programmed — your entered fz
Enter a programmed fz above to see the feed, MRR, power and the actual chip thickness your entered setting really produces.
Concepts & diagrams
Axial depth of cut — ADOC / ap
ADOC (ap) is how deep the cutter engages along its own axis — the depth of cut measured parallel to the spindle. It is limited by the tool's length of cut (LOC): cutting deeper than the LOC puts the shank, not the flutes, in the material.
Radial width of cut — RDOC / ae
RDOC (ae) is the width of the cut measured across the cutter — how much of the diameter is engaged radially. A small RDOC (for example 10% of the diameter) engages only a small arc of the cutter; a full-width slot engages 100%.
Feed per tooth (fz)
fz is the distance the tool advances while one tooth is engaged — the load each cutting edge is asked to carry, before any chip-thinning effect. Feed rate = RPM × flutes × fz.
Chip thickness (hmax)
hmax is the thickest part of the chip a tooth actually produces in this cut. At low radial engagement it is thinner than the programmed fz, because each tooth is in the material for only a short arc. hmax is a length — it is shown in inches or millimetres, never in IPT.
Chip thinning
When RDOC is less than half the diameter, each tooth cuts over a shorter arc, so the chip comes out thinner than the programmed fz (hmax < fz). This is radial chip thinning. HEM uses it in reverse: fz is raised by the chip-thinning factor (RCTF) so the actual hmax stays at the target. Above 50% engagement no compensation applies (factor = 1).
RDOC comparison — locked ADOC / RPM / target hmax
Edit the RDOC percentages to compare strategies at constant target chip thickness. Local engagement in corners may exceed the selected RDOC. “Within entered limits” only means a row does not exceed the numbers you typed — it is never a guarantee that a row is safe. The highest-MRR row is NOT automatically the best choice — judge power, torque and tool load as well.
| RDOC % of D | Engagement % | Target hmax | Chip factor | Required fz | Feed (target) | MRR | Power | Torque | Limit check |
|---|
Tools & Materials Library
Read-only records. Cutting recommendations are recorded only with a traceable source; where no sourced data exists, the status is honestly shown as “Insufficient Data” and no values are invented.
Materials (ISO groups)
| Grade | Family | ISO | Condition | Cutting-data status |
|---|
Tools
| Tool | Diameter | Flutes | Tool material / coating | LOC | Recommendations (Vc / fz / hmax) | Data status |
|---|
Engineering Formula Reference
Milling
- Vc = π × D × RPM / 1000 [m/min, D in mm]
- RPM = 1000 × Vc / (π × D)
- Feed = RPM × flutes × fz
- MRR = ap × ae × Feed (straight, continuously engaged pass only)
HEM — radial chip thinning (90° peripheral side milling)
- r = ae / D
- Chip thickness factor = 2 × √(r × (1 − r)) for 0 < r ≤ 0.5; = 1 for r > 0.5
- hmax = fz × factor; fz required = hmax target / factor; RCTF = 1 / factor
- Engagement angle θ = acos(1 − 2r)
Turning
- RPM = 1000 × Vc / (π × D); Feed = RPM × f [mm/rev]
- CSS (G96): actual RPM = min(calculated RPM, machine RPM limit) — the cap is mandatory
- Theoretical finish (ideal approximation only): Rz ≈ f² / (8 × Rn), Ra ≈ f² / (32 × Rn)
Drilling
- Feed = RPM × f [mm/rev]; MRR = (π × D² / 4) × Feed
- Tip length = (D / 2) / tan(point angle / 2) — geometry allowance only
Tapping
- Lead = pitch × starts; Feed = RPM × lead (M10 × 1.5 at 500 RPM → 750 mm/min)
Power & torque
- Cutting power = MRR × kc / 60,000,000 [kW, kc user-supplied]
- Torque = 60,000 × P / (2π × RPM) [Nm]
Sources: Sandvik Coromant machining formulas; Harvey Performance radial chip thinning guide; Haas CNC programming references (G96). Cutting recommendations depend on the tool manufacturer — this app never invents them.
Turning Calculator
Not yet implemented. The turning mathematics (RPM, feed, CSS with mandatory RPM cap, theoretical finish) are implemented and unit-tested in the calculation engine — only this interface is pending. Nothing here is faked.
Drilling Calculator
Not yet implemented. The drilling mathematics (penetration rate, MRR, tip-length allowance, L/D ratio) are implemented and unit-tested in the calculation engine — only this interface is pending. Nothing here is faked.
Tapping & Threading
Not yet implemented. The tapping mathematics (lead = pitch × starts, feed = RPM × lead, TPI conversions) are implemented and unit-tested in the calculation engine — only this interface is pending. Nothing here is faked.
Thread Milling
Not yet implemented — neither the interface nor a validated tool-center feed-correction model is included in this build. Nothing here is faked.
Surface Finish & Geometry
Not yet implemented as an interface. Ball-nose scallop and effective-diameter mathematics are implemented and unit-tested in the engine.
Machine Power & Torque
A standalone module is not built yet. Power, torque and machine-limit checks ARE working inside the Milling and HEM modules (enter kc and machine limits there).
Machining Time & Cost
Not yet implemented. Nothing here is faked.
Machine Profiles
Not yet implemented. Machine limits can be entered directly in the Milling and HEM modules for now. Nothing here is faked.
Saved Calculations
Not yet implemented. Nothing here is faked.