01
The first article misses the tolerance band
A bore comes in 0.02 mm over nominal and the bearing will not seat. Rework means a second setup, a second inspection, and a week lost from your build schedule.
Machined to print
Custom CNC Parts
GreatLight machines parts to ±0.005 mm, from one prototype to 10,000+ pieces. Upload a drawing, get a quote and a free DFM analysis within 12 hours.
±0.005 mm toleranceNo minimum order127 CNC machinesISO 9001 / IATF 16949Quote in 12 hours100% inspection
±0.005 mmMachining tolerance
127High-precision CNC machines
12 hQuote and DFM analysis
3–5 daysParts ship after production starts
Where it goes wrong
Four failures we see on outsourced machined parts
Most of these show up after the parts reach your floor, not before.
02
Drawings bounce back with no explanation
Your file sits in a queue for days, then returns with a price and no notes. Nobody flagged the 0.5 mm wall or the tool that cannot reach the corner until the parts arrive.
03
The quote changes after the order
Setup, deburring, anodizing and inspection land as separate line items later. The number you approved and the number on the invoice stop matching, and finance asks you why.
04
Ten samples pass, the run does not
A prototype shop nails the first five pieces, then the 500-piece lot drifts as tools wear and fixtures move. You spend the next month sorting good parts from bad by hand.
How we run it
Machining that holds the print from piece one to piece ten thousand
One shop handles the prototype, the pilot lot and the production run on the same programs.
Geometry
Five-axis work for parts that need three setups elsewhere
16 simultaneous 5-axis machining centers cut angled faces, deep pockets and contoured surfaces in one clamping. Fewer setups means fewer datum shifts, and datum shifts are where most tolerance stacks fall apart.
We machine up to 4,000 mm on the long axis, with travels of 750 × 1,150 × 550 mm and 600 × 600 × 600 mm on the mid-size platforms. A Ø400 mm rotary table covers round parts that need milling and turning in the same cycle.
- 1Undercuts and compound anglesCut without repositioning the part or building a second fixture.
- 2Thin walls down to 0.5 mmLight finishing passes and controlled chip load keep the wall from springing.
- 3One datum, one reportCritical features measured against the drawing's own datum scheme.
Review
DFM notes come back with the price, not after it
Every upload gets a manufacturability review inside 12 hours. If a corner radius is smaller than the tool that has to cut it, or a tolerance is tighter than the function needs, you hear about it before you commit to a purchase order.
That review often removes cost. Loosening one non-critical bore from ±0.01 mm to ±0.05 mm can drop a part from a 5-axis job to a 3-axis one. We tell you which features drive the price so you can decide what actually matters.
- 1Tolerance triageWe separate features that need ±0.005 mm from those that do not.
- 2Material alternatives6061-T6 instead of 7075 where strength allows, at lower cost and faster stock.
- 3Finish sequencingMasking and anodizing planned before the part is cut, not bolted on later.
Selection
Which process fits your part
A rough guide we use when quoting. Final call depends on the drawing.
| Part feature | Process | Why |
|---|---|---|
| Prismatic housings, plates, brackets | 3-axis milling | Simple access from one direction, lowest setup cost |
| Parts with features on four sides | 4-axis milling | Rotary index cuts four faces without re-clamping |
| Contoured pockets, impellers, angled ports | 5-axis simultaneous | Tool stays normal to the surface, no hand blending |
| Shafts with milled flats or cross holes | Mill-turn | Turning and milling in one cycle, one datum |
| Wall thickness under 1 mm | 5-axis, light finishing | Controlled radial engagement limits deflection |
| Round parts over Ø300 mm | Ø400 mm rotary table | Indexed positions hold concentricity |
| Parts up to 4,000 mm long | Large-travel 5-axis | Single setup on the long axis |
| Prototype quantities under 10 | 3-axis or mill-turn | No fixture investment to amortize |
What we make
Six ways we turn your file into a finished part
Most projects use two or three of these together.
01
5-axis CNC machining
Complex geometry in one setup, up to ±0.005 mm on critical features. Suits aerospace brackets, medical housings and impellers.
02
CNC milling and turning
3-axis and 4-axis milling plus mill-turn centers for shafts, fittings and bushings. Round and prismatic work under one roof.
03
Rapid prototyping
One to fifty pieces cut from the production material, so the prototype behaves like the part you will ship.
04
Sheet metal fabrication
Bent, formed and welded enclosures and brackets when a machined block would waste material.
05
Surface finishing
Anodizing, plating, powder coating, bead blasting and laser marking, coordinated before the part leaves the machine.
06
Die casting and vacuum casting
For housings where machining every part is too slow. Tool up once, machine only the critical faces.
Scope
Tolerance, finish and material ranges
Numbers below are what we quote against by default.
| Item | Range | Notes |
|---|---|---|
| Achievable tolerance | ±0.005 mm (±0.0002 in) | On critical features with controlled setup |
| General milling tolerance | ±0.05 mm | Typical for non-critical dimensions |
| Fine surface finish | Ra 0.2–0.8 μm | Adds a finishing pass, quoted separately |
| Standard machined finish | Ra 1.6–3.2 μm | Default as-machined surface |
| Aluminium | 6061, 2024, 5052, 6063, 6082, 7075, ADC12 | 6061-T6 for most structural parts |
| Stainless steel | 303, 304, 316L, 420, 440C, 17-4PH | 316L for medical and marine |
| Titanium and special | TA1, TA2, TC4, Inconel, magnesium AZ31B | Quoted on geometry and stock |
| Plastics | ABS, PC, POM, PA, PEEK, PP, HDPE | PEEK for high-temperature wear parts |
| Laser marking | 1.5 mm minimum character height | Below that the mark blurs |
| Maximum part size | 4,000 mm on the long axis | Larger travels on request |
Why GreatLight
The numbers behind the shop
Fifteen years of machining, three plants, one set of quality rules.
15Y
Machining since 2011
Fifteen years of production work for aerospace, automotive, medical and industrial customers. The process sheets have been through a lot of revisions.
±0.005
Millimeters on critical features
Held on 5-axis and mill-turn platforms with in-process monitoring and a final CMM check before parts ship.
99.99%
Qualification rate
Measured across shipped lots. Parts that fail inspection get reworked or remade before they leave the building.
150
Technicians and engineers
Programmers, machinists and quality staff across three wholly-owned plants in Dongguan and Singapore.
4
Quality systems in place
ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. Reports on request with each order.
1
Minimum order quantity
One piece is a valid order. The same programs run the prototype and the 10,000-piece release.
7,600 m²Manufacturing space
16Simultaneous 5-axis centers
12 hQuote turnaround
<2%Historical late-delivery rate
What the sectors demand
Requirements we build to, by industry
Aerospace brackets and fittings
Thin ribs, tight true position and full traceability from raw stock to final inspection.
- ±0.005 mm
- 5-axis one setup
- Material certs on file
Automotive and EV housings
PPAP-level documentation, consistent lots and finishes that survive under-hood thermal cycling.
- IATF 16949
- 10,000+ piece runs
- 99.99% qualification
Medical instrument components
316L and titanium parts with burr-free edges, passivated surfaces and cleanroom-ready packaging.
- ISO 13485
- Ra 0.2–0.8 μm
- 100% inspection
Robotics and automation frames
Long rails and mounting plates kept flat and square so the motion system aligns on assembly.
- 4,000 mm travel
- Flatness held
- Anodized finish
FAQs
Questions engineers ask before the first order
What file formats do you accept for a quote?
STEP and IGES are the safest for 3D geometry. For 2D work, PDF drawings with datums, tolerances and finish callouts give us everything we need.
If you only have a sample part, we can measure it and work from the scan. Send photos with a scale reference first so we can confirm the approach.
How tight a tolerance can you actually hold across a production run?
±0.005 mm on critical features, with ±0.05 mm on general dimensions. The tight number depends on the feature, the material and how many setups it takes.
Tolerances tighter than the function requires raise cost without adding value. If your drawing calls for ±0.005 mm on a cosmetic edge, we will say so in the DFM notes.
What is the smallest order you will take?
One piece. There is no minimum order quantity, and the setup is not priced differently for a single unit than for the first piece of a larger lot.
Prototype and production runs use the same programs, so nothing gets re-proven when you scale up.
How do you handle my drawings and IP?
Uploads stay secure and confidential. We do not share files outside the quoting and programming team.
An NDA is available on request before you send anything. We can sign yours or provide ours.
What inspection comes with an order?
Every order ships with a standard inspection report. That covers a raw material check, in-process monitoring and a final inspection before packing.
Full dimensional reports, material certificates and first article inspection documents are available on request. Ask at the quoting stage so we can quote the inspection time correctly.
Which materials are hard to machine, and what should I know?
Titanium, Inconel and hardened tool steels cut slowly and wear tools fast, so they cost more per part and take longer. They are still routine work for us.
If a part does not need titanium's strength-to-weight ratio, 7075 or 17-4PH often does the job at lower cost and shorter lead time. We will tell you when the substitution is safe.
When does the quote come back, and when do parts ship?
Quote and free DFM analysis within 12 hours of receiving a complete file. Production can start within 24 hours of order confirmation.
Parts ship in 3–5 days for most geometries. Larger parts, exotic materials and multi-step finishes take longer, and we say so in the quote rather than after.
Can you match a finish I already use?
Yes. Send a sample or a finish spec and we will match it. Anodizing can be clear, colored, hardcoat or conductive, and we also run electroless nickel, zinc, silver, gold, powder coating and black oxide.
Bead blasting, tumbling, brushing and polishing are done in-house, which keeps the finish sequence under one schedule.
Send a drawing, get a quote in 12 hours
Upload your file and we will return a price with DFM notes. No minimum order, no charge for the review.
Quote in 12 hours100% inspection before shipmentNo minimum order quantity
