CNC Processing Network: How It Changes Part Manufacturing

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  What a CNC processing network actually delivers
• 2
  What a CNC processing network is, in practical terms
• 3
  Matching part geometry to the right machine in the network
• 4
  Holding ±0.005 mm across a networked production run
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  Material and finish choices that keep the network efficient
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  How a job moves through the network, step by step
• 7
  When a CNC processing network fits and when it does not

A CNC processing network is a coordinated group of machining, finishing, and inspection resources that share one set of process documents. The point is not the size of the group. The point is that your drawing, material certificate, and inspection plan stay attached to the same job number from first quote to final shipment.

In a fragmented supply chain, a milling shop cuts the part, a second shop anodizes it, and a third measures it. Each handoff adds a new setup, a new fixture, and a new chance for a dimension to drift. A network removes most of those handoffs by keeping the operations in one production plan.

GreatLight runs this model with 3 wholly-owned plants, 7,600 m² of floor space, and 150 technicians. The company has been machining since 2011, so 15 years of process data sit behind the quotes. That history is what makes a network useful: the shop already knows which material and feature combinations fight back.

The network idea only pays off when the scope stays narrow. A network is good at machined metal and plastic parts with defined geometry. It is a poor fit for open-ended design work, for assemblies that need field installation, or for parts where the tolerance is still being negotiated between two internal teams.

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  ScopeMachined parts with a released drawing, a material callout, and a finish spec.
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  Handoff riskFewer vendors means fewer datum changes and fewer re-qualification loops.
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  Data trailOne job number follows the part through cutting, finishing, and inspection.

The fastest way to lose money on a quote is to send a part to the wrong machine class. A 5-axis job priced on a 3-axis mill looks cheap until the shop has to build three fixtures and re-clamp four times. A simple bracket priced on a 5-axis center looks expensive for no reason.

Use the 5-axis route when the part has compound angles, deep pockets on more than one face, or features that must stay true to a single datum. GreatLight runs 16 simultaneous 5-axis machining centers, which suits impellers, manifolds, and contoured housings. Four-axis work covers parts that need rotation but not full contouring, and 12 four-axis mills handle that load.

Three-axis machines still do most of the volume. With 27 three-axis machines and 16 mill-turn centers, the network can run prismatic plates, shafts, and turned fittings without tying up a 5-axis spindle. Mill-turn is the better choice when a part has both a turned body and milled flats, because one setup holds concentricity.

Size sets the ceiling. The largest travel is 4,000 × 400 × 150 mm for long, slender parts. Medium work fits 750 × 1,150 × 550 mm or 600 × 600 × 600 mm. Compact parts run on 500 × 500 × 450 mm and 500 × 310 × 200 mm machines, and a Ø400 mm rotary table covers round features that need indexing.

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  5-axisCompound angles, contoured surfaces, single-datum accuracy.
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  Mill-turnTurned body plus milled flats; concentricity in one setup.
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  3-axisPrismatic plates and simple pockets at lower hourly cost.
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  Size checkConfirm envelope before quoting; 4,000 mm is the long-part limit.

A tolerance claim means nothing without a measurement plan. ±0.005 mm (±0.0002 in) is achievable on rigid setups with temperature-stable material and a sharp tool. It is not achievable on a thin wall that deflects under clamping pressure, no matter which machine cuts it.

The network controls this with three checks. Raw material is verified before cutting. In-process monitoring catches drift while the part is still in the fixture. Final inspection runs on 100% of parts before shipment, with reports available on request. That sequence is what keeps the qualification rate at 99.99%.

Surface finish follows the same logic. A sealing face may need Ra 0.2–0.8 μm, a bearing bore Ra 0.8–1.6 μm, and a non-critical bracket only Ra 1.6–3.2 μm. Specifying a finer finish than the function needs adds polishing time and cost with no gain.

Watch the feature interactions. A tight bore next to a thin rib will move when the rib is milled. A slot with a 0.5 mm corner radius needs a small tool, and small tools deflect. In those cases, we would rather adjust the geometry during DFM than promise a number the part cannot hold.

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  IncomingMaterial grade and condition verified before the first cut.
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  In-processDimensional checks while the part is still located in the fixture.
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  Final100% inspection before shipment; reports on request.

Aluminium is the default for prototypes and housings. 6061 and 6061-T6 machine cleanly and anodize well. 7075 gives higher strength for brackets and fixtures. 2024, 5052, 5083, 6063, 6082, and ADC12 cover the rest of the common aluminium work, including die-cast bodies that need secondary machining.

Stainless covers food, medical, and marine parts. Grades 303 and 304 are routine. 316 and 316L resist corrosion better. 17-4PH (SUS630) and 440C are for wear or higher strength. Steel work runs from 1018 and 1045 through 4130, 4140, 4340, and A36, with tool steel for dies and punches.

Copper and brass families such as C101, C110, C36000, and beryllium copper show up in busbars and connectors. Titanium and nickel alloys, including TA1, TA2, TC4 (Ti-6Al-4V) and Inconel, are machinable but need slower speeds, more tool changes, and a realistic schedule. Magnesium AZ31B and AZ91D cut fast but require careful chip handling.

Plastics behave differently. ABS, PC, PMMA, POM, PA, PEEK, PP, HDPE, and carbon fibre all machine, but PEEK and carbon fibre wear tools quickly. Finishing options include anodizing in clear, colour, hardcoat, or conductive form, electroless nickel, zinc, silver, and gold plating, powder coating, black oxide, bead blasting, tumbling, brushing, and polishing. Laser marking is available down to 1.5 mm character height.

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  Fast route6061-T6 and 303 stainless give the shortest lead time.
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  Hard routeInconel and Ti-6Al-4V need slower feeds and more tool wear budget.
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  Finish noteAnodize before laser marking if the mark must survive handling.