CNC Machining Services Industries We Serve
A supplier list is easy to collect. The hard part is matching a shop to your industry's real acceptance criteria. This guide covers the seven industries we machine for and the checks that decide whether a shop belongs on your approved vendor list.
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What matters before you send the RFQ
What each industry demands from a CNC shop
Use the strictest column that applies to your part, not the average.
| Industry | Typical tolerance band | Key qualification | Common material |
|---|---|---|---|
| Aerospace | ±0.005 mm on critical features | Material certs and full inspection records | 7075 aluminium, Ti-6Al-4V, 17-4PH |
| Automotive & EV | ±0.01 mm on mating surfaces | IATF 16949:2016 process control | 6061-T6, ADC12, 4140 steel |
| Medical Devices | ±0.005 mm, Ra 0.2–0.8 μm | ISO 13485:2016 and clean handling | 316L stainless, PEEK, titanium |
| Robotics & Automation | ±0.01 mm on joint bores | Repeatability across the run | 7075 aluminium, 1045 steel, POM |
| Electronics | ±0.02 mm on housings | Cosmetic finish control | 6063, 5052, PC, ABS |
| Industrial Machinery | ±0.02 mm general machining | Drawing-to-part conformity | 1018, 1045, A36, cast iron |
| New Energy | ±0.01 mm on busbar contacts | Flatness and conductivity checks | C110 copper, 6061, 316L |
How the cnc machining services industries we serve differ in practice
Seven industries send us drawings, and no two send the same package. Aerospace buyers attach material certificates, a first article inspection plan and a surface finish callout on almost every feature. Automotive buyers care about process control: can you repeat the same 40,000 parts with a documented control plan? Medical buyers ask about cleaning, deburring and how the shop keeps implant-grade 316L separate from general stainless. The part geometry may look similar across all three. The evidence package does not.
We founded GreatLight in 2011 and now run 3 wholly-owned plants covering 7,600 m² in Dongguan, plus a Singapore factory at No.3 Joo Koon Circle, Singapore 629032. That footprint matters for selection because different industries buy capacity in different shapes. Aerospace and robotics orders are usually low volume, high mix, and need 5-axis work on complex geometry. Automotive and new energy orders are higher volume and need stable fixturing and repeatable cycle times.
The practical test is simple. Ask the shop to name the last three jobs it ran in your industry and describe the inspection method used on the tightest feature. A shop that machines for medical devices will talk about Ra 0.2–0.8 μm finishes and burr-free edges without prompting. A shop that only serves general industrial machinery will talk about cycle time. Neither answer is wrong, but only one fits a surgical instrument housing.
- 1AerospaceTitanium and 7075 parts with full traceability; 5-axis for contoured surfaces.
- 2Automotive & EVIATF 16949 process control for engine, transmission and EV structural parts.
- 3Medical DevicesISO 13485 production of surgical instruments, implants and diagnostic hardware.
- 4Robotics, electronics, machinery, new energyJoint housings, enclosures, gears, shafts, busbars and heat-sink components.
Matching machine capability to part geometry
A 5-axis machining center is not automatically better than a 3-axis machine. It is better when the part has features on multiple faces, deep pockets with angled walls, or contoured surfaces that would need three separate fixtures on a 3-axis setup. Every extra setup adds a datum shift, and datum shifts eat tolerance budget. If your part is a flat plate with holes on one face, a 3-axis machine will hold ±0.005 mm just as well and cost less.
Our capacity covers the range: 16 simultaneous 5-axis machining centers, 12 four-axis mills, 27 three-axis machines, 16 mill-turn centers and 127 high-precision CNC machines in total. Maximum processing size reaches 4,000 mm, with travels of 4,000 × 400 × 150 mm and 750 × 1,150 × 550 mm on the larger platforms. Small parts run on 500 × 500 × 450 mm or 500 × 310 × 200 mm travels with a Ø400 mm rotary table.
The selection question is whether the shop's largest machine matches your largest part without splitting it. Splitting a 3,000 mm frame into two pieces and bolting them together introduces a joint that will move under load. If your drawing shows a one-piece frame, confirm the shop has the travel before you send the RFQ. This single check eliminates most mismatches.
Certifications that actually change your vendor approval
Certificates on a website are marketing. Certificates that map to your quality system are procurement evidence. We hold ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. For an automotive Tier 1 buyer, the IATF certificate is the entry ticket. For a medical device company, ISO 13485 governs how the supplier is audited and how deviations are handled. For any buyer sending proprietary CAD files, ISO 27001 covers how those files are stored and who can open them.
Tolerance claims need the same treatment. We hold ±0.005 mm (approximately ±0.0002 in) on qualified features, and surface finishes from Ra 0.2–0.8 μm for fine work up to Ra 1.6–3.2 μm for as-machined surfaces. Those numbers mean something only when tied to a measurement method. Ask whether the shop uses a CMM, a profilometer or a vision system, and whether the report ships with the parts.
We inspect 100% of parts before shipment, with raw material checks, in-process monitoring and a final inspection stage. Reports are available on request. That last phrase is the one to test. A shop that generates inspection data as standard practice will send a report in a day. A shop that has to re-measure after the fact will take longer and may not have the original setup data.
Lead time, MOQ and quote terms to compare
Three commercial numbers separate a good fit from a bad one: quote turnaround, production start and order minimum. We return a quotation and free DFM analysis within 12 hours. Production can start within 24 hours of approval. Parts ship in 3–5 days for standard work. Our historical late-delivery probability sits below 2%.
MOQ is where most small teams get blocked. Many shops quote a minimum of 100 or 500 pieces because setup cost dominates the job. We run with no minimum order quantity, from a single prototype to 10,000+ part runs. That matters when you are validating a design and cannot commit to volume. The same shop, the same fixtures and the same inspection history carry through to the production run.
Compare quote terms line by line. Does the quote include material certification? Does it include finishing, or is anodizing billed separately? Are inspection reports included or an add-on? A low unit price with four exclusions is not the lowest total cost. Ask for the exclusions in writing before you compare two suppliers.
Common mistakes when selecting a CNC supplier
The most expensive mistake is sending a 2D drawing when the shop needs 3D geometry. Contoured surfaces, fillets and draft angles cannot be quoted accurately from two views. Send STEP or IGES files plus a PDF drawing with tolerances and finish callouts. It shortens the quote cycle and removes the argument later about what was specified.
The second mistake is quoting material by name only. Aluminium 6061 and 7075 machine differently, weld differently and anodize differently. Stainless 303 machines freely; 316L work-hardens and needs different feeds. If the drawing says aluminium without a grade, the shop will pick the cheapest one that machines, and your part may fail a corrosion or strength requirement.
The third mistake is ignoring finishing in the schedule. Anodizing, plating, powder coating and laser marking add days and sometimes require masking. Laser marking has a minimum character height of 1.5 mm, so a 0.8 mm serial number will not reproduce. Plan finishing into the timeline and confirm who owns the masking spec.
- 1Send 3D filesSTEP or IGES plus a tolerance drawing prevents quote disputes.
- 2Name the material grade6061-T6, 316L, 7075 or 17-4PH, not just aluminium or stainless.
- 3Specify the finishInclude Ra target, color and masking requirements on the drawing.
- 4Confirm report scopeState whether you need material certs and dimensional reports with the shipment.
Seven steps to qualify a CNC shop for your industry
Run these in order. Each step eliminates suppliers before you spend engineering time.
- 1List the acceptance criteriaWrite down tolerance, surface finish, material grade, certification and inspection report needs. A medical part might read ±0.005 mm, Ra 0.8 μm, 316L, ISO 13485, full dimensional report.
- 2Filter by certificationDrop any shop without the certificate your quality system requires. Automotive needs IATF 16949:2016; medical needs ISO 13485:2016; file security needs ISO 27001:2022.
- 3Check machine travel against part sizeCompare your largest part envelope to the shop's stated travel. We cover up to 4,000 mm with 4,000 × 400 × 150 mm on the largest platform. If the part must be one piece, a split design is a red flag.
- 4Confirm axis count matches geometryUse 5-axis for multi-face or contoured features, 3-axis for single-face flat work. Ask how many setups the shop plans, since each setup consumes tolerance budget.
- 5Send 3D files for DFMUpload STEP and PDF files. We return a quote and free DFM analysis within 12 hours, flagging thin walls, deep pockets and unachievable tolerances before you commit.
- 6Test with a prototype orderOrder one part with no MOQ commitment. Inspect the finish, the edges and the dimensional report. Production can start within 24 hours of approval if the prototype passes.
- 7Lock the production termsConfirm lead time, finishing ownership, report scope and NDA coverage. Parts ship in 3–5 days for standard runs, and uploads stay confidential under NDA on request.
Questions buyers ask before awarding the job
Can one shop serve both prototype and production volumes?
Yes, if the shop keeps setup data and fixtures from the prototype run. We hold no minimum order quantity, so a single prototype and a 10,000+ part run go through the same process chain.
The risk to check is whether the prototype was machined on a different machine class than the production run. If the prototype came off a 5-axis center and production moves to a 3-axis line, expect a new first article inspection.
Which certifications should a medical device buyer verify?
ISO 13485:2016 is the core requirement, because it governs how the supplier controls production, traceability and nonconforming parts for medical hardware.
Pair it with ISO 9001:2015 for general quality system coverage. If you share patient-related or proprietary design files, ISO 27001:2022 covers the information side.
How do I compare quotes when the unit prices differ by 40%?
Line up the inclusions. Check whether material certification, surface finishing, inspection reports and packaging are inside the price. A 40% gap usually means one quote excludes two or three of those items.
Also compare the assumed material grade and the stated lead time. A quote based on 6061 instead of 7075 will look cheaper and will not meet the drawing.
What tolerance can actually be held across a production run?
We hold ±0.005 mm (about ±0.0002 in) on qualified features, with a 99.99% qualification rate. That figure depends on part geometry, material and fixturing, not on the machine alone.
Long thin parts and thin-walled housings are the usual exceptions. Send the model for DFM and the achievable tolerance gets confirmed before quoting.
How are confidential designs protected during quoting?
Uploads stay secure and confidential, and we sign an NDA on request. ISO 27001:2022 covers how design files are stored and accessed internally.
If your program has export-control or ITAR-like restrictions, raise it in the first message so the shop can confirm it can accept the files before you upload them.
Which finishing options affect the schedule most?
Anodizing, plating and powder coating add the most time because they run as separate operations, often outsourced or batched. Bead blasting, tumbling and brushing are faster.
Laser marking is quick but has a minimum character height of 1.5 mm. Anything smaller will not reproduce cleanly, so adjust the artwork before release.
Send your drawing and get a fit assessment
Upload your 3D files and we will return a quotation with free DFM analysis within 12 hours, covering tolerance, material, finishing and inspection scope.
12-hour quoteNo MOQ100% inspectionNDA on request
More from the shop floor
We publish setup notes, tooling trials and inspection data from the factory floor.
