01
Tolerance creep on wall thickness
A 1.5 mm wall machines to 1.35 mm on the second batch. The bearing bore no longer holds press fit, and the assembly fails leak testing. Stack-up errors accumulate quietly across three or four features.
CNC Machining · Dongguan & Singapore
Custom High Precision CNC Machining Metal Parts
We machine metal parts from prototype to 10,000+ piece runs with ±0.005 mm tolerance, 127 CNC machines, and 100% inspection before shipment.
±0.005 mm tolerance16 five-axis centersNo MOQISO 9001:2015Quote in 12 hours
15Years in precision machining
127High-precision CNC machines
±0.005 mmAchievable tolerance
99.99%Qualification rate
Where parts go wrong
Four problems that show up after the parts arrive
02
Surface finish misses the callout
Drawing says Ra 0.8 μm. The incoming parts read Ra 1.8 μm. Seals wear faster, sliding surfaces gall, and the customer rejects the lot at incoming inspection.
03
Quotes that take a week
You send a STEP file on Monday and hear nothing until Friday. The RFQ window closes, the program manager picks another shop, and the schedule slips before a chip is cut.
04
Setup changes between runs
Batch one fits. Batch two does not. The shop re-clamped the part in a different vise or moved the zero point, and now the bolt pattern is off by 0.05 mm.
How we hold the numbers
Machining that repeats, not just machines
Process control, not luck, keeps a ±0.005 mm callout alive across batches.
Setup control
One setup, one zero point, every run
Fixture plates and soft jaws are tagged and stored with the program number. When the repeat order lands six months later, the operator reloads the same plate and the same work offset. Nothing gets re-dialed from scratch.
For parts with features on four or five faces, we cut them on a simultaneous 5-axis center instead of flipping the part. That removes the re-clamp error that shows up as a 0.05 mm bolt-pattern shift.
- 1Tagged fixturesStored with program number and offset sheet
- 25-axis in one setupFewer flips, fewer datum shifts
- 3Offset sheet per jobOperator follows recorded values, not memory
Inspection
Measured before it ships, not after it fails
Every job gets a first-article check against the drawing, in-process checks at defined intervals, and a final inspection before packing. Reports go out with the parts when the customer asks for them.
Critical dimensions are measured on the machine where possible, so a drifting tool is caught at part 3 instead of part 300. Tool wear offsets get adjusted mid-run.
- 1First articleFull dimensional report against the drawing
- 2In-process checksIntervals set by feature criticality
- 3100% before shipmentNothing leaves without final inspection
Fit check
Which process fits your part
Pick by geometry and tolerance first, then by quantity.
| Part situation | Process | Why |
|---|---|---|
| Prismatic part, 2-3 faces, ±0.05 mm | 3-axis mill | Lowest cycle time |
| Rotational features on a milled body | 4-axis mill | One setup, indexed faces |
| Complex 3D contour, ±0.01 mm | 5-axis simultaneous | No re-clamp error |
| Shaft with milled flats | Mill-turn | Turning and milling in one chuck |
| Thin wall under 1 mm | 5-axis, light passes | Less clamping distortion |
| Prototype, 1 to 5 pieces | 3-axis + manual bench | No fixture cost |
| Hardened tool steel, 50 HRC+ | Grind after mill | Holds the tolerance |
| Large frame, 4,000 mm long | Large-travel mill | Fits in one setup |
What we run
Machining services on the floor
01
5-Axis CNC Machining
16 simultaneous 5-axis centers for contoured surfaces, deep pockets, and parts that would need four setups on a 3-axis machine.
02
4-Axis CNC Machining
12 four-axis mills for indexed work on cylindrical bodies, cross-drilled holes, and milled flats around a turning axis.
03
3-Axis CNC Machining
27 three-axis machines for prismatic parts, plates, and housings where cycle time matters more than reach.
04
CNC Milling & Turning
16 mill-turn centers combine turning and milling in one chuck, so shafts with flats and slots keep their concentricity.
05
Rapid Prototyping
First articles in 3-5 days from aluminum, steel, or plastic stock. Useful when the design is still moving.
06
Surface Finishing
Anodizing, plating, powder coating, bead blasting, and laser marking, coordinated with outside finishers we already qualify.
Capacity
Machine and spec range
| Item | Range | Notes |
|---|---|---|
| Tolerance | ±0.005 mm | ±0.0002 in |
| Surface finish | Ra 0.2–0.8 μm | Fine finish on request |
| Max part size | 4,000 mm | Long travel 4,000 × 400 × 150 mm |
| Medium travel | 750 × 1,150 × 550 mm | And 600 × 600 × 600 mm |
| Compact travel | 500 × 500 × 450 mm | And 500 × 310 × 200 mm |
| Rotary table | Ø400 mm | 4th axis work |
| Order quantity | 1 to 10,000+ | No minimum order quantity |
| Quote turnaround | 12 hours | With free DFM analysis |
Why GreatLight
Numbers behind the machines
15Y
Machining since 2011
Three wholly-owned plants and 150 technicians. The same team quotes, programs, and inspects your part.
±0.005 mm
Tolerance we hold
Not a brochure number. It comes from tagged fixtures, in-process checks, and tool-wear offsets adjusted mid-run.
127
CNC machines
16 five-axis, 12 four-axis, 27 three-axis, and 16 mill-turn centers. Capacity for both prototypes and production.
12 h
Quote and DFM
Send a STEP file and get a price plus manufacturability notes within 12 hours. Production can start within 24 hours.
ISO
Four certifications
ISO 9001:2015, IATF 16949:2016, ISO 13485:2016, and ISO 27001:2022. Certificates on request.
NDA
Confidentiality
Uploads are secure and confidential. A non-disclosure agreement is available on request before drawings change hands.
7,600 m²Manufacturing space
150Technicians
3Wholly-owned plants
<2%Historical late-delivery rate
Industry fit
What these industries ask for, and what we deliver
Industrial machinery
Frames and housings that must bolt together without rework on site.
- ±0.005 mm
- Ra 1.6 μm
- 3-axis
Automotive & EV
Brackets and housings that need IATF 16949:2016 process control.
- IATF 16949
- 10,000+ runs
- 100% inspection
Medical devices
Stainless components with clean surfaces and documented inspection.
- ISO 13485
- 316L
- Full report
Electronics
Enclosures and heat-sink parts with tight flatness on mating faces.
- 6061-T6
- ±0.01 mm
- Anodized
FAQs
Questions engineers ask before sending a file
What tolerance can you actually hold on a metal part?
We hold ±0.005 mm on features that are reachable in one setup and measured in-process. On thin walls or long unsupported sections, the practical limit loosens because the part moves under clamping and cutting forces.
Send the drawing and we will tell you which callouts are easy, which need a second operation, and which are not worth the cost.
How do I know the part will fit before I commit to a full run?
Ask for a first article. We machine one piece, measure the critical dimensions, and send the report with the part. You check fit on your assembly before we cut the rest.
For parts where the design is still moving, a prototype run of 1 to 5 pieces is usually cheaper than guessing.
Do you have a minimum order quantity?
No. We run one prototype or 10,000+ pieces on the same floor. The setup cost is the same either way, so the per-piece price drops as quantity rises.
For a single piece, expect to pay for programming and fixturing. That cost is real and we quote it openly.
What file formats do you need for a quote?
STEP or IGES for the 3D model, plus a PDF of the drawing with tolerances, surface finish, material, and any notes on critical features.
If you only have a 2D drawing, send it. We can model the part and note the assumptions in the quote.
How fast can you ship?
Quotation and free DFM analysis come back within 12 hours. Production can start within 24 hours of order confirmation. Most parts ship in 3 to 5 days.
Complex parts, outside finishing, or material that has to be ordered will take longer. We tell you the real date, not the optimistic one.
Which materials do you machine most?
Aluminum 6061 and 7075, stainless 303 and 316L, mild and alloy steels, brass, copper, and titanium TC4. Plastics like POM, PEEK, and ABS are common for prototypes.
Material choice usually follows corrosion, weight, or wear requirements. We can suggest alternatives if your first pick is hard to source.
How do you protect our drawings and design?
Uploads are secure and confidential. We sign a non-disclosure agreement on request, before any file changes hands.
Our information security management is certified to ISO 27001:2022. Access to customer files is limited to the people who program and inspect the job.
What if the parts arrive out of tolerance?
Send photos and measurement data. We compare them against our inspection record for that job number and find out where the process drifted.
If we made the error, we rework or remachine at our cost. If the drawing was ambiguous, we fix the drawing note together so the next run is clean.
Send a drawing, get a number back today
Upload your STEP file and drawing. You get a price, a DFM note, and a real lead time within 12 hours.
12-hour quote100% inspectionNo minimum order quantity
