CNC Lathe Machining 904L Stainless Steel

VT machining provides CNC Lathe Machining 904L Stainless Steel for customers who need accurate, repeatable 904L Stainless Steel components. The machinability of 904L Stainless Steel is moderate; work-hardens, so positive-rake tooling and steady feeds are used to avoid glazing, so we set the operation up specifically for this grade.

CNC Lathe Machining Capability for 904L Stainless Steel

  • Austenitic/martensitic grades
  • Corrosion resistant
  • Tolerance to ±0.01 mm
  • Typical hardness 70–200 HB (annealed)

904L Stainless Steel Material Data

904L Stainless Steel — typical properties, quoted for 304
Density8.00 g/cm³
Tensile strength515 MPa
Yield strength (0.2%)205 MPa
Hardness170 HB
Melting point1400–1450 °C
Thermal conductivity16.2 W/m·K
Thermal expansion17.3 ×10⁻⁶/K
Electrical conductivity2.4%
Machinability (C36000 = 100%)45%
Grades we run303, 304/304L, 316/316L, 321, 410, 416, 420, 17-4PH, 2205 duplex

Published typical values for 304. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining 904L Stainless Steel — what actually causes trouble

It work-hardens the moment a tool dwells. Constant feed and positive-rake tooling; a rubbing pass leaves a glazed skin the next tool cannot get through.

Machining 904L Stainless Steel with CNC Lathe Machining

When turning 904L Stainless Steel, machinability is moderate; work-hardens, so positive-rake tooling and steady feeds are used to avoid glazing. Our process plan reflects this so the finished part holds its tolerances without distortion or poor finish.

Documented parameters for 904L Stainless Steel mean predictable cycle times and stable, repeatable results.

Achievable Tolerances for CNC Lathe Machining 904L Stainless Steel

CNC Lathe Machining 904L Stainless 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.

Why 904L Stainless Steel?

Customers select 904L Stainless Steel for CNC Lathe Machining because it is corrosion resistant, strong and hygienic. We handle grade verification and any required heat treatment or finishing.

Secondary Operations & Finishing

Most 904L Stainless Steel parts need some finishing, which we manage in-house or through vetted partners. Options include deburring and edge-breaking, heat treatment, surface grinding, polishing, and plating or anodising for corrosion resistance and appearance. Give us the finished-part requirement and we will sequence every operation correctly.

Design Tips for CNC Lathe Machining 904L Stainless Steel

Small design adjustments often cut cost and lead time. Consistent diameters, standard thread forms and avoiding extremely long, slender features help 904L Stainless 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 Lathe Machining Quality & Inspection

Quality is built in, not inspected on. We monitor key features during the run and confirm them at final inspection, with CMM verification available for tight tolerances. We provide the inspection and traceability records your quality system requires.

CNC Lathe Machining Tolerances & Surface Finish

Turned 904L Stainless 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.

Exact achievable figures depend on the alloy, the feature size and the part geometry. Tell us which dimensions are critical and we will advise feasibility up front.

Applications of CNC Lathe Machining 904L Stainless Steel

904L Stainless Steel parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.

How to Order CNC Lathe Machining 904L Stainless Steel

Starting your project takes one email. Send your CAD or 2D drawing, the 904L Stainless Steel grade and condition, the quantity and any finish or inspection requirements. We respond quickly with price, lead time and any DFM notes, in clear English.

Finishing Options for 904L Stainless Steel

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Citric passivationASTM A967 / AMS 2700, removes free iron
Electropolish5–25 µm removedRa improves by roughly half, hygienic surface
Brushed / grainedRa 0.4–1.6 µmNo. 4 finish, directional
PVD coating2–5 µmTiN, TiCN for wear surfaces
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 Lathe Machining 904L Stainless 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 904L Stainless 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.

904L Stainless Steel in Other Processes

Related

Send the drawing, the 904L Stainless Steel condition and the quantity — pricing and lead time come back the same or next business day.

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Frequently Asked Questions

Which industries use CNC Lathe Machining 904L Stainless Steel parts?

CNC Lathe Machining 904L Stainless Steel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise 904L Stainless Steel components are required.

Does CNC Lathe Machining 904L Stainless Steel require dedicated tooling?

Most 904L Stainless Steel turning work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.

What material thickness or size range suits CNC Lathe Machining 904L Stainless Steel?

Turned 904L Stainless 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 Lathe Machining 904L Stainless Steel?

CNC Lathe Machining prototypes for 904L Stainless 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.