Looking for reliable CNC Swiss Machining Alloy Steel? VT machining manufactures Alloy Steel parts to tight tolerances and consistent quality. Alloy Steel is high strength and hardenability for demanding parts, so the process is set up specifically for the material.
Starting Parameters for CNC Swiss Machining Alloy Steel
| Cutting speed (carbide) | 145-240 m/min |
|---|---|
| Feed | 0.1-0.3 mm/rev |
| Spindle speed, Ø8 mm bar | 5770-9550 rpm |
| Insert / tool class | ISO P — CVD-coated carbide |
| Coolant | Emulsion (6-8%) |
| Length-to-diameter capability | up to ~20:1 |
Shown for 4140 Alloy Steel, the most common Alloy Steel grade we see for CNC Swiss Machining. Starting values for 4140 Alloy Steel, Annealed or pre-hardened (28-32 HRC); optimised on the first article.
CNC Swiss Machining Capability for Alloy Steel
- Ø1–32 mm bar
- Slenderness without deflection
- Tolerance to ±0.003 mm
- High-volume small parts
Alloy Steel material properties, finishing options and grade notes are on our CNC Turning Alloy Steel page.
How CNC Swiss Machining Alloy Steel Works
The Alloy Steel bar or billet rotates in the spindle while single-point tools shape outer diameters, bores, faces, grooves and threads. Constant surface speed control keeps cutting conditions stable from large to small diameters.
We start from your supplied geometry and tolerance scheme. The setup is designed to minimise re-clamping, which protects positional accuracy across features. A first article is verified against the drawing before the balance of the batch is released.
Achievable Tolerances for CNC Swiss Machining Alloy Steel
| Feature | Standard | Precision |
|---|---|---|
| Outside diameter | ±0.05 mm | ±0.005 mm |
| Bore diameter | H9 | H6 |
| Length / shoulder position | ±0.10 mm | ±0.020 mm |
| Concentricity OD to ID | 0.05 mm TIR | 0.010 mm TIR |
| Roundness | 0.02 mm | 0.005 mm |
| Thread class | 6g / 2A | 4h / 3A |
| Surface finish, as turned | Ra 1.6 µm | Ra 0.4 µm |
Standard is what a normal quotation assumes. Precision is available on nominated features and is priced separately, because it needs extra setups, in-process gauging and CMM verification. Call out only the features that need it — blanket-tightening a drawing is the single most common reason a quote comes back expensive.
Design Tips for CNC Swiss Machining Alloy Steel
Small design adjustments often cut cost and lead time. Consistent diameters, standard thread forms and avoiding extremely long, slender features help Alloy Steel turned parts stay concentric and economical. If you send your model early, we will return practical DFM feedback before you commit to production.
CNC Swiss Machining Tolerances & Surface Finish
Turned Alloy Steel holds diameter tolerances to about ±0.005 mm with concentricity within 0.01 mm and good roundness. Turned finishes of Ra 0.4–0.8 µm are achievable with finishing passes and sharp tooling.
The tightest tolerances are reserved for the features your drawing flags as critical. Share your tolerance scheme and we will confirm what is realistic before quoting.
Applications of CNC Swiss Machining Alloy Steel
Alloy Steel parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
Typical Alloy Steel Parts for CNC Swiss Machining
Illustrative examples of CNC Swiss Machining Alloy Steel parts and the callouts that usually drive the process plan. They show the kind of work that fits this process; they are not specific customer orders.
Threaded fitting
- Material
- Alloy Steel
- Size
- Ø22 hex × 38 mm
- Key callouts
- G3/8" thread class 4h, bore H8, sealing face Ra 0.8 µm
- Batch
- 2,500 pcs
Run on a sub-spindle lathe so the back face is finished without a second setup.
Connector pin
- Material
- Alloy Steel
- Size
- Ø3.0 × 24 mm
- Key callouts
- OD ±0.005 mm, straightness 0.02 mm over length
- Batch
- 20,000 pcs
Swiss-turned from bar with a guide bushing; nothing else holds Ø3 mm over 24 mm.
Valve seat
- Material
- Alloy Steel
- Size
- Ø28 × 14 mm
- Key callouts
- Seat angle 45° ±0.1°, roundness 0.005 mm, Ra 0.2 µm
- Batch
- 800 pcs
Seat finished with a single-point diamond pass, no interruption.
No drawing yet? Build one in the browser.
Set the metal, dimensions and features, watch the 3D model update as you type, then switch to the 2D sheet to add dimensions and tolerances. Download it or send it straight to us with your RFQ.
What We Need to Quote CNC Swiss Machining Alloy Steel
- GeometrySTEP or IGES for the 3D model, plus a PDF drawing if you have tolerance callouts. A dimensioned sketch is enough to start.
- MaterialThe exact Alloy Steel grade and condition — temper, heat-treat state or hardness. If you are not sure, tell us the function and we will suggest one.
- QuantityPrototype count and the expected annual volume. Both change how the part is made and therefore what it costs.
- TolerancesWhich features are critical. Everything else runs to our standard tolerance, which is what keeps the price sensible.
- FinishSurface treatment, cosmetic requirements, and any faces that must be masked.
- DocumentsWhether you need a material certificate, dimensional report, FAIR or PPAP with the shipment.
Missing something from the list is not a problem — send what you have. We will come back with the specific questions rather than a generic form.
Other Metals for CNC Swiss Machining
Other Processes for Alloy Steel
Send the drawing, the Alloy Steel grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
What surface finish is achievable on Alloy Steel with CNC Swiss Machining?
Surface finish on Alloy Steel is controlled to your specification; we confirm the achievable Ra against your callout.
Does CNC Swiss Machining Alloy Steel require dedicated tooling?
Most Alloy Steel turning work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.
Which industries use CNC Swiss Machining Alloy Steel parts?
CNC Swiss Machining Alloy Steel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Alloy Steel components are required.
What material thickness or size range suits CNC Swiss Machining Alloy Steel?
Turned Alloy Steel parts are produced from bar or chuck stock across a wide diameter range.