CNC Boring S275JR Steel from VT machining delivers precision S275JR Steel parts made to your exact drawing. Boring enlarges and finishes existing holes to precise diameter, roundness and surface finish, with parameters tuned to S275JR Steel, which is strong, economical and widely available.
CNC Boring Capability for S275JR Steel
- Carbon/low-alloy grades
- Economical & weldable
- Tolerance to ±0.02 mm
- Hardenable by heat treat
S275JR Steel Material Data
| Density | 7.85 g/cm³ |
|---|---|
| Tensile strength | 585 MPa |
| Yield strength (0.2%) | 450 MPa |
| Hardness | 170 HB |
| Melting point | 1420–1460 °C |
| Thermal conductivity | 51.9 W/m·K |
| Thermal expansion | 11.5 ×10⁻⁶/K |
| Electrical conductivity | 9% |
| Machinability (C36000 = 100%) | 57% |
| Grades we run | 1018, 1045, 1215, A36, S45C, St37, 4140 (see alloy steel) |
Published typical values for 1045. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
Rust. Bare steel flash-rusts within hours in a humid container, so parts are oiled or passivated before packing unless you specify otherwise.
Machining S275JR Steel with CNC Boring
S275JR Steel behaves predictably under CNC Boring once parameters are dialled in: machinability is good to excellent depending on carbon content; free-machining grades cut cleanly, and we tune the operation accordingly.
We hold reference parameters for this grade, so repeat orders of S275JR Steel run consistently from one batch to the next.
Achievable Tolerances for CNC Boring S275JR 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 Quality & Inspection
We control quality throughout the process, not just at the end. In-process checks plus final inspection — including CMM where specified — keep every S275JR Steel part to print. Inspection reports, material certificates and first-article documentation can be supplied on request.
CNC Boring Tolerances & Surface Finish
Turned S275JR 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.
Final tolerances are governed by the material's behaviour, wall thickness and overall stiffness. We give honest DFM feedback if a callout would be costly or better achieved another way.
Why S275JR Steel?
S275JR Steel is chosen when a part needs what this grade offers — it is strong, economical and widely available. We confirm the grade and any temper or heat-treat condition with you before machining.
Secondary Operations & Finishing
Finished S275JR Steel parts can move straight into secondary operations under one roof. Typical add-ons are deburring, passivation, anodising, plating, blasting, polishing and laser marking. We coordinate the whole chain so you receive complete, inspection-ready parts.
Design Tips for CNC Boring S275JR Steel
We are happy to suggest design tweaks that improve manufacturability. Consistent diameters, standard thread forms and avoiding extremely long, slender features help S275JR 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 S275JR Steel
Customers order CNC Boring S275JR Steel components for everything from instrumentation to structural and functional assemblies. Whether you need a single prototype or recurring production volume, the same process discipline applies.
How to Order CNC Boring S275JR Steel
Getting a quote is simple. Share your model, the material grade, your quantity and target tolerances. You receive a clear quotation with lead time and honest manufacturability feedback.
Finishing Options for S275JR Steel
| Finish | Thickness / effect | Why it gets specified |
|---|---|---|
| Black oxide | 1–2 µm | Mild corrosion resistance, no dimensional change |
| Zinc plate + clear/yellow | 5–12 µm | ASTM B633, general corrosion protection |
| Nickel plate (electroless) | 10–25 µm | Uniform in bores, 500 HV after bake |
| Phosphate | 5–10 µm | Paint key, mild lubricity |
| Powder coat | 60–120 µm | RAL colours |
| Deburr / edge break | 0.05–0.3 mm | All parts unless the drawing says otherwise |
| Bead blast | Ra 1.6–3.2 µm | Uniform matt finish, hides tool marks |
| Laser marking | — | Part number, lot code, data matrix |
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 S275JR 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 S275JR 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.
S275JR Steel in Other Processes
Related
Send the drawing, the S275JR Steel condition and the quantity — pricing and lead time come back the same or next business day.
Request a QuoteFrequently Asked Questions
What surface finish is achievable on S275JR Steel with CNC Boring?
Surface finish on S275JR Steel is controlled to your specification; we confirm the achievable Ra against your callout.
Why is S275JR Steel a good choice for CNC Boring?
S275JR Steel is strong, economical and widely available, which makes it well suited to CNC Boring. We tune the process to the alloy so the finished S275JR Steel turning part meets your dimensional and functional requirements.
Which industries use CNC Boring S275JR Steel parts?
CNC Boring S275JR Steel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise S275JR Steel components are required.
Does CNC Boring S275JR Steel require dedicated tooling?
Most S275JR Steel turning work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.
Can VT machining make custom S275JR Steel parts to my drawing?
Yes. S275JR Steel S275JR 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.