Precision CNC: A Working Customer Centric CNC Solution

• 1
  Key takeaways
• 2
  What a customer centric CNC solution actually changes
• 3
  Which parts fit, and which should go elsewhere
• 4
  How we read your drawing before quoting
• 5
  From RFQ to shipped parts: the working sequence
• 6
  Where customer-centric machining breaks down
• 7
  Matching part type to machine platform

Most machine shops will quote anything you send. A customer centric CNC solution works the other way: an engineer reads the drawing first, checks whether the geometry and tolerance can be held on the machines we run, and tells you where the risk is. That first review is where cost is decided, not on the invoice.

GreatLight runs three wholly-owned plants covering 7,600 m² in Dongguan, plus a factory in Singapore, with 150 technicians and 127 high-precision CNC machines. That footprint matters for one reason: we can pick the machine that fits the part instead of squeezing it onto whatever is free. Sixteen simultaneous 5-axis centers, 16 mill-turn centers, 12 four-axis mills and 27 three-axis machines cover most of the work.

The difference shows up in the feedback loop. When a wall is too thin for the finish you specified, you hear it in the DFM report within 12 hours, before tooling is committed. When a datum scheme will not repeat across a 4,000 mm part, you hear that too. Working this way costs us more engineering time per quote. It saves far more on rework.

We have held ±0.005 mm (±0.0002 in) on production parts since 2011. That number is not a shop-wide default. It is a capability we apply where the drawing needs it, on features we have reviewed.

• 1
  Engineer-reviewed quotesA machinist or process engineer signs off before the price goes out.
• 2
  One point of contactThe person who reviews your part stays on it through shipment.
• 3
  Reports on requestRaw material check, in-process monitoring and final inspection records.

Five-axis work pays off when a part has features on multiple faces that would otherwise need two or three setups. One setup removes the re-fixturing error and usually removes a fixture cost. It also shortens the schedule, because the second operation is not waiting in a queue.

Turning plus milling on one platform suits shafts, housings and connectors with cross-holes, flats or slots. Our mill-turn centers handle that in a single cycle. If your part is a simple prismatic block with holes on one face, a 3-axis machine will be faster and cheaper. We will say so.

Size is the other filter. Our largest travel is 4,000 × 400 × 150 mm, with medium platforms at 750 × 1,150 × 550 mm and 600 × 600 × 600 mm, and compact platforms at 500 × 500 × 450 mm and 500 × 310 × 200 mm. A Ø400 mm rotary table covers round work that needs indexing. Parts beyond those envelopes are not a fit.

Material matters too. We machine aluminium 6061, 7075 and ADC12, stainless 316L and 17-4PH, steels including 4140 and 4340, titanium TC4 (Ti-6Al-4V), Inconel, magnesium AZ31B, and plastics from POM to PEEK. Titanium and Inconel cut slowly and eat tool life, so thin walls in those alloys need a design review early.

• 1
  Good fitMulti-face geometry, tight true position, low-to-mid volume, hard alloys in small features.
• 2
  Weak fitSingle-face plates, parts larger than 4,000 mm, decorative surfaces with no functional tolerance.
• 3
  Ask firstWall thickness under 0.8 mm, deep pockets with a high depth-to-diameter ratio, mirror finishes.

The first pass is a tolerance audit. We separate dimensions that control function from dimensions that are simply drawn to three decimals. A bolt clearance hole does not need ±0.005 mm, and calling it out that way adds inspection time without adding value.

Next comes the datum check. A datum that sits on a surface machined in a later operation creates a chase problem. We flag it and propose a datum that can be established in the first setup. This is the single most common change we ask for.

Then the finish. As-machined surfaces run Ra 1.6–3.2 μm, standard high-finish work runs Ra 0.8–1.6 μm, and fine finishes reach Ra 0.2–0.8 μm. A fine finish across a whole part is rarely necessary. Restricting it to sealing faces and bearing seats keeps cycle time down.

Finally, the quantity and schedule. There is no minimum order quantity. A single prototype and a 10,000+ part run both start with the same DFM review. Production can begin within 24 hours of drawing release, and parts typically ship in 3–5 days.

• 1
  Tolerance auditSeparate functional dimensions from cosmetic ones before pricing.
• 2
  Datum strategyKeep datums reachable in the first setup where possible.
• 3
  Finish zonesCall out sealing and bearing surfaces, leave the rest as-machined.
• 4
  Schedule realityTell us the date you need parts, not just the quantity.

It starts with a STEP or IGES file plus a PDF drawing. If you only have a solid model, send it anyway. We quote from the model and note the dimensions that need a callout before production. Quotation and free DFM analysis come back within 12 hours.

Once you approve the DFM changes, we release material and start production, which can happen within 24 hours. Raw material is checked on receipt. In-process monitoring runs through the operations, and final inspection is 100% before shipment. Our qualification rate is 99.99%, and the historical late-delivery probability is below 2%.

Finishing is handled in-house where possible: anodizing in clear, colour, hardcoat or conductive; electroless nickel, zinc, silver and gold plating; powder coating and black oxide; bead blasting, tumbling, brushing and polishing; laser marking and engraving down to 1.5 mm character height.

When the order ships, you get the parts and the inspection records you asked for. If a dimension is marginal, you hear it from us before the box leaves, not after your incoming inspection finds it.

• 1
  12 hoursQuote and DFM analysis, sent together.
• 2
  24 hoursProduction start after DFM approval.
• 3
  3–5 daysTypical shipping window for released jobs.
• 4
  100%Inspection coverage before shipment.

The model fails when the customer is not in the loop. If a drawing changes after setup, the fixture and the first-article report are both invalid. Freezing the revision before release is worth more than any discount.

It also fails when tolerances are copied from an old print without checking function. We see ±0.005 mm on hole positions that only need clearance. That drives up inspection hours and can push a part onto a slower machine for no reason. A tolerance audit usually removes cost without touching the design intent.

Third, material substitutions made late. Swapping 6061 for 7075 changes cutting forces and can move a thin-wall dimension. Tell us about substitutions before the first cut, not during finishing.

Last, silence on surface finish. If your sealing face needs Ra 0.4 μm and the drawing says nothing, you will get as-machined finish. We will ask, but the answer is faster if it is already on the print.

• 1
  Frozen revisionLock the drawing before tooling and fixturing start.
• 2
  Tolerance auditRemove tight calls that carry no function.
• 3
  Material changesConfirm before the first cut, not after.
• 4
  Finish calloutsState Ra on every functional surface.