CNC Gear Cutting Alloy Steel

CNC Gear Cutting Alloy Steel from VT machining delivers precision Alloy Steel parts produced to your exact drawing. CNC gear cutting forms precise tooth profiles for spur, helical, bevel and worm gears, and we tune every parameter to the behaviour of Alloy Steel, which is high strength and hardenability for demanding parts.

CNC Gear Cutting Alloy Steel at VT machining
CNC Gear Cutting Alloy Steel — produced in-house at VT machining

CNC Gear Cutting Capability for Alloy Steel

  • Multiple gear types
  • Profile accuracy class
  • Custom modules
  • Hardened-blank ready

Alloy Steel Material Data

Alloy Steel — typical properties, quoted for 4140 (Q&T)
Density7.85 g/cm³
Tensile strength655–1020 MPa
Yield strength (0.2%)415–900 MPa
Hardness197–302 HB
Melting point1416 °C
Thermal conductivity42.6 W/m·K
Thermal expansion12.3 ×10⁻⁶/K
Electrical conductivity8%
Machinability (C36000 = 100%)65% (annealed)
Grades we run4140, 4340, 8620, 20CrMnTi, 42CrMo4, 20MnCr5

Published typical values for 4140 (Q&T). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining Alloy Steel — what actually causes trouble

Heat treatment moves the part. Anything held tighter than ±0.02 mm is machined soft, hardened, then ground or hard-turned to final size.

How CNC Gear Cutting Alloy Steel Works

Tooth profiles are generated in the Alloy Steel blank by a synchronised cutter, then refined to the required accuracy class. Module, pressure angle and helix are programmed from your gear data.

Every job begins from your CAD model or 2D drawing. Fixturing and tool paths are planned so the most critical dimensions are produced in the most rigid, repeatable setup. Critical dimensions are checked on the first part and monitored through the run.

Achievable Tolerances for CNC Gear Cutting Alloy Steel

CNC Gear Cutting Alloy Steel — achievable tolerances
FeatureStandardPrecision
Accuracy classDIN 8 / AGMA 10DIN 6 / AGMA 12
Profile deviation0.020 mm0.008 mm
Lead deviation0.020 mm0.008 mm
Pitch deviation (cumulative)0.040 mm0.015 mm
Runout0.030 mm0.010 mm
Tooth surface finishRa 1.6 µmRa 0.4 µm (ground)
Module rangem0.5–m8m1–m6

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 Gear Cutting Tolerances & Surface Finish

Gear features are produced to a specified DIN/AGMA accuracy class, with profile and lead controlled for quiet, durable running under load.

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.

CNC Gear Cutting Quality & Inspection

Consistent quality comes from disciplined process control. Critical dimensions on Alloy Steel parts are checked in-process and verified at final inspection using calibrated instruments and, where required, CMM measurement. Full documentation — dimensional reports, mill certs, FAIR — is available when your programme needs it.

Secondary Operations & Finishing

We complete Alloy Steel components with the secondary steps your drawing calls for. We arrange heat treatment, surface treatment, marking and assembly as needed. Tell us the final spec and we will plan the full route so parts arrive ready to use.

Working with Alloy Steel

Alloy Steel offers a useful combination of properties: it is high strength and hardenability for demanding parts. Those characteristics shape how we approach gear manufacturing — from tool and parameter selection to work-holding and coolant.

If your application is sensitive to alloy condition, we agree the specification in writing and document it. Stock is sourced from reputable suppliers so what you order is what you receive.

Design Tips for CNC Gear Cutting Alloy Steel

A few design choices make a real difference to cost and quality. Providing complete gear data (module, pressure angle, profile shift, quality class) lets us produce Alloy Steel gears right the first time. If you send your model early, we will return practical DFM feedback before you commit to production.

Applications of CNC Gear Cutting Alloy Steel

CNC Gear Cutting of Alloy Steel supports parts across aerospace, medical, automotive, electronics, semiconductor, energy and general industrial sectors. We scale from one-off prototypes to ongoing production while holding the same quality.

How to Order CNC Gear Cutting Alloy Steel

Ordering Alloy Steel parts is straightforward. Provide the drawing, material, quantity and any certification needs. Our engineers reply — in English — with feasibility, pricing and a realistic lead time, usually within one business day.

Parts We Have Run in Alloy Steel

Three representative CNC Gear Cutting Alloy Steel jobs, with the callouts that actually drove the process plan. Yours will differ — these are here so you can judge whether your part is in our range before you spend time on an RFQ.

Worm and wheel set

Material
Alloy Steel
Size
m3, single start
Key callouts
Backlash 0.05–0.10 mm as a matched pair
Batch
120 sets

Supplied as matched sets and marked, because mixing pairs loses the backlash spec.

Internal ring gear

Material
Alloy Steel
Size
m2.5, z72, ID 190 mm
Key callouts
DIN 8, pitch deviation 0.03 mm
Batch
150 pcs

Shaped rather than hobbed — an internal gear leaves no room for a hob to run out.

Bevel gear pair

Material
Alloy Steel
Size
m2, z20/z40, 90° axes
Key callouts
DIN 8, mounting distance ±0.03 mm
Batch
200 sets

Contact pattern checked on a rolling tester before release.

Finishing Options for Alloy Steel

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Through hardening30–55 HRC, ground afterwards for tight sizes
Case hardening (carburise)0.3–1.2 mm case58–62 HRC surface, tough core
Nitride0.1–0.5 mm900–1100 HV, minimal distortion
Black oxide1–2 µmCosmetic + light corrosion protection
Zinc / nickel plate5–25 µmCorrosion protection
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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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.

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What We Need to Quote CNC Gear Cutting 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 Gear Cutting

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.

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Frequently Asked Questions

Does CNC Gear Cutting Alloy Steel require dedicated tooling?

Most Alloy Steel gear cutting work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.

Can VT machining make custom Alloy Steel parts to my drawing?

Yes. Alloy Steel Alloy Steel gear cutting 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.

What gear accuracy class can you achieve on Alloy Steel?

Gear accuracy is specified to DIN/AGMA classes appropriate to the application. Profile and lead are controlled so Alloy Steel gears run accurately and quietly under load.

Why is Alloy Steel a good choice for CNC Gear Cutting?

Alloy Steel is high strength and hardenability for demanding parts, which makes it well suited to CNC Gear Cutting. We tune the process to the alloy so the finished Alloy Steel gear cutting part meets your dimensional and functional requirements.

How clean are the edges produced by CNC Gear Cutting on Alloy Steel?

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

What is the typical lead time and minimum order for CNC Gear Cutting Alloy Steel?

CNC Gear Cutting prototypes for Alloy 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.