CNC Boring Spring Steel from VT machining delivers precision Spring Steel parts produced to your exact drawing. Boring enlarges and finishes existing holes to precise diameter, roundness and surface finish, and we tune every parameter to the behaviour of Spring Steel, which is high yield strength and elastic recovery.
Starting Parameters for CNC Boring Spring Steel
| Cutting speed (carbide) | 95-155 m/min |
|---|---|
| Feed | 0.07-0.21 mm/rev |
| Spindle speed, Ø30 mm bore | 1010-1640 rpm |
| Insert / tool class | ISO P — CVD-coated carbide |
| Coolant | Emulsion (6-8%) |
Shown for Spring Steel (65Mn / SK5 / 1075), the most common Spring Steel grade we see for CNC Boring. Starting values for Spring Steel (65Mn / SK5 / 1075), Annealed or hardened & tempered strip; optimised on the first article.
CNC Boring Capability for Spring Steel
- Bore tolerance to IT6
- Roundness within 0.005 mm
- Fine boring heads
- Large-diameter capability
Spring Steel material properties, finishing options and grade notes are on our CNC Turning Spring Steel page.
How CNC Boring Spring Steel Works
The Spring 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 Boring Spring 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.
CNC Boring Tolerances & Surface Finish
Turned Spring 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.
Design Tips for CNC Boring Spring Steel
Small design adjustments often cut cost and lead time. Consistent diameters, standard thread forms and avoiding extremely long, slender features help Spring Steel turned parts stay concentric and economical. If you send your model early, we will return practical DFM feedback before you commit to production.
Applications of CNC Boring Spring Steel
Spring Steel parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
Typical Spring Steel Parts for CNC Boring
Illustrative examples of CNC Boring Spring 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.
Nozzle body
- Material
- Spring Steel
- Size
- Ø12 × 46 mm
- Key callouts
- Ø0.6 mm orifice ±0.01 mm, internal taper 20°
- Batch
- 600 pcs
Orifice EDM-drilled after turning; a drill wanders at that diameter.
Bearing spacer
- Material
- Spring Steel
- Size
- Ø35 / Ø22 × 9 mm
- Key callouts
- Thickness ±0.005 mm, parallelism 0.005 mm
- Batch
- 4,000 pcs
Turned then double-disc ground — thickness this tight is not a lathe job.
Valve seat
- Material
- Spring 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 Boring Spring 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 Spring 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 Boring
Other Processes for Spring Steel
Send the drawing, the Spring 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 tolerances can you hold for CNC Boring Spring Steel?
Achievable tolerances for Spring Steel turning depend on the alloy, geometry and feature size. Turning holds diameter tolerances to around ±0.005 mm with concentricity within 0.01 mm. Exact figures are confirmed against your drawing callouts.
How clean are the edges produced by CNC Boring on Spring Steel?
Machined Spring Steel edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.
Which industries use CNC Boring Spring Steel parts?
CNC Boring Spring Steel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Spring Steel components are required.
Can VT machining make custom Spring Steel parts to my drawing?
Yes. Spring Steel turning is made to order from your CAD/2D drawing. Share your geometry, material grade, tolerance and quantity and we will confirm feasibility, lead time and pricing.