CNC Factory the Future of Precision Manufacturing

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  Key takeaways
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  What to compare before you place a purchase order
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  Tolerance: what a CNC factory the future of precision manufacturing really has to prove
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  MOQ, volume and where unit cost actually moves
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  Lead time: read the clock from the right starting point
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  Certifications and inspection: match the paperwork to your industry
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  How to vet a CNC factory in 6 steps

Every quote says precision. The useful question is narrower: which machine holds which tolerance on which part size? A 16-machine 5-axis cell and a compact 3-axis mill do not share the same practical limits, and a shop that quotes the same number for both is guessing.

At GreatLight we publish ±0.005 mm (about ±0.0002 in) as a working tolerance, backed by 16 simultaneous 5-axis centers, 12 four-axis mills, 27 three-axis machines and 16 mill-turn centers. Spindle and thermal behavior differ across that fleet, so the tolerance applies to the feature, not to the whole drawing.

Inevitably some features need more room. A 4,000 mm long part on a 4,000 × 400 × 150 mm travel machine behaves differently from a 500 × 500 × 450 mm housing. Thin walls, deep pockets and long unsupported bores push you toward Ra 1.6–3.2 μm as-machined surfaces and looser position tolerances. Say so on the drawing.

Metrology closes the loop. A tolerance claim without a measuring method is unverifiable, so ask what touches the part: CMM, height gauge, micrometer, optical comparator. We run raw material checks, in-process monitoring and final inspection, with reports on request.

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  Tightest published tolerance±0.005 mm (±0.0002 in) on controlled features
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  Fine finish availableRa 0.2–0.8 μm on sealing and bearing surfaces
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  Standard machined finishRa 1.6–3.2 μm for brackets, housings and plates
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  Check before you commitAsk which machine will run your part, not which shop

A minimum order quantity is a scheduling decision, not a technical one. A shop with a single product line wants long runs because setup is expensive to interrupt. A job shop with 127 machines can absorb a one-off prototype between production jobs.

GreatLight runs no minimum order quantity, from one prototype to 10,000+ part runs. That matters at the design stage, when you need three units to test a fit and cannot justify tooling. Fixtures and soft jaws carry the setup, so the second batch does not repeat the first article inspection cost.

Unit price drops as volume rises, mostly through setup amortization and material buying. Do not expect the curve to be steep on a part that needs 5-axis work on every face. Do expect a real step down once the process is proven and the fixture is written into the work instructions.

Where buyers get hurt is splitting the process. A prototype house machines the sample, then a production plant re-quotes and changes the stock allowance. Keep both stages with one supplier and the drawing stays in one set of hands.

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  Prototype quantityOne piece is an acceptable order
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  Production range10,000+ parts without moving to a different plant
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  Setup strategySoft jaws and fixtures, reusable across batches
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  Cost driver to watchNumber of faces needing 5-axis access

Lead time numbers are easy to inflate because everyone counts from a different event. Some shops start when the purchase order lands. Others start when the material arrives. The honest start point is the drawing review, because that is where manufacturability problems surface.

We quote and return a free DFM analysis within 12 hours, and production can start within 24 hours after that. Parts ship in 3–5 days for typical machined work. Those intervals assume the drawing is stable and material is either in stock or standard.

Exotic stock changes everything. Inconel, Ti-6Al-4V and 17-4PH may need mill certification before cutting. If your schedule is tight, name the material on the RFQ and ask whether it is on the shelf. A two-day material delay beats a scrapped first batch.

Late delivery is a process symptom, not bad luck. A shop that tracks its own on-time rate can tell you what it is. Our historical late-delivery probability is below 2%, and we would rather show that number than promise a date we cannot control.

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  Quote and DFMWithin 12 hours of a complete RFQ
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  Cutting startsWithin 24 hours after DFM sign-off
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  Shipping window3–5 days for standard machined parts
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  Schedule riskSpecialty alloys and mill certs add days

A certificate on a website is a starting point. What you need is the scope statement: does the audit cover the machining process, the plant that will run your part, and the inspection step? Ask for the certificate number and the issuing body.

GreatLight holds ISO 9001:2015 for quality management, IATF 16949:2016 for automotive, ISO 13485:2016 for medical devices and ISO 27001:2022 for information security. The last one matters when you upload CAD files, since it covers how those files are stored and who can open them.

Inspection is where certification becomes tangible. We inspect 100% of parts before shipment: raw material check on arrival, in-process monitoring during cutting, and a final inspection against the drawing. Reports are available on request, including dimensional results for critical features.

For medical and aerospace work, add traceability. Material certs, heat lot numbers and finish certificates should travel with the parts. If a supplier cannot produce them after the fact, the parts are hard to release.

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  ISO 9001:2015Baseline quality management across the plants
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  IATF 16949:2016Automotive and EV production expectations
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  ISO 13485:2016Medical device manufacturing controls
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  ISO 27001:2022Data security for uploaded drawings and models