CNC Turning Q345 Steel

VT machining provides CNC Turning Q345 Steel for customers who need accurate, repeatable Q345 Steel components. The machinability of Q345 Steel is good to excellent depending on carbon content; free-machining grades cut cleanly, so we set the operation up specifically for this grade.

CNC Turning Capability for Q345 Steel

  • Carbon/low-alloy grades
  • Economical & weldable
  • Tolerance to ±0.02 mm
  • Hardenable by heat treat

Q345 Steel Material Data

Q345 Steel — typical properties, quoted for 1045
Density7.85 g/cm³
Tensile strength585 MPa
Yield strength (0.2%)450 MPa
Hardness170 HB
Melting point1420–1460 °C
Thermal conductivity51.9 W/m·K
Thermal expansion11.5 ×10⁻⁶/K
Electrical conductivity9%
Machinability (C36000 = 100%)57%
Grades we run1018, 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.

Machining Q345 Steel — what actually causes trouble

Rust. Bare steel flash-rusts within hours in a humid container, so parts are oiled or passivated before packing unless you specify otherwise.

Machining Q345 Steel with CNC Turning

Q345 Steel behaves predictably under CNC Turning 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 Q345 Steel run consistently from one batch to the next.

Achievable Tolerances for CNC Turning Q345 Steel

CNC Turning Q345 Steel — achievable tolerances
FeatureStandardPrecision
Outside diameter±0.05 mm±0.005 mm
Bore diameterH9H6
Length / shoulder position±0.10 mm±0.020 mm
Concentricity OD to ID0.05 mm TIR0.010 mm TIR
Roundness0.02 mm0.005 mm
Thread class6g / 2A4h / 3A
Surface finish, as turnedRa 1.6 µmRa 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 Turning 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 Q345 Steel part to print. Inspection reports, material certificates and first-article documentation can be supplied on request.

CNC Turning Tolerances & Surface Finish

Turned Q345 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.

Design Tips for CNC Turning Q345 Steel

We are happy to suggest design tweaks that improve manufacturability. Consistent diameters, standard thread forms and avoiding extremely long, slender features help Q345 Steel turned parts stay concentric and economical. If you send your model early, we will return practical DFM feedback before you commit to production.

Why Q345 Steel?

Q345 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 Q345 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.

Applications of CNC Turning Q345 Steel

Customers order CNC Turning Q345 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 Turning Q345 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 Q345 Steel

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Black oxide1–2 µmMild corrosion resistance, no dimensional change
Zinc plate + clear/yellow5–12 µmASTM B633, general corrosion protection
Nickel plate (electroless)10–25 µmUniform in bores, 500 HV after bake
Phosphate5–10 µmPaint key, mild lubricity
Powder coat60–120 µmRAL colours
Deburr / edge break0.05–0.3 mmAll parts unless the drawing says otherwise
Bead blastRa 1.6–3.2 µmUniform matt finish, hides tool marks
Laser markingPart number, lot code, data matrix
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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.

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What We Need to Quote CNC Turning Q345 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 Q345 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.

Q345 Steel in Other Processes

Related

Send the drawing, the Q345 Steel condition and the quantity — pricing and lead time come back the same or next business day.

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Frequently Asked Questions

How clean are the edges produced by CNC Turning on Q345 Steel?

Machined Q345 Steel edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.

What material thickness or size range suits CNC Turning Q345 Steel?

Turned Q345 Steel parts are produced from bar or chuck stock across a wide diameter range.

What is the typical lead time and minimum order for CNC Turning Q345 Steel?

CNC Turning prototypes for Q345 Steel can be produced quickly and scaled to series production. Send your drawing and quantity and we will advise lead time and any minimum order.

Why is Q345 Steel a good choice for CNC Turning?

Q345 Steel is strong, economical and widely available, which makes it well suited to CNC Turning. We tune the process to the alloy so the finished Q345 Steel turning part meets your dimensional and functional requirements.

What surface finish is achievable on Q345 Steel with CNC Turning?

Surface finish on Q345 Steel is controlled to your specification; we confirm the achievable Ra against your callout.