NZ CNC Processing Service: What to Check Before You Order
This guide is for engineers and buyers sourcing a NZ CNC processing service for metal and plastic parts. It covers the tolerance, lead time, MOQ, certification and quote checks that decide whether a supplier can actually hold your drawing. Read it and you can shortlist two or three shops instead of ten.
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Key takeaways
Six checks, and what a good answer looks like
Use this table to score suppliers on the same criteria.
| Check | Weak answer | Strong answer |
|---|---|---|
| Tolerance claim | ±0.05 mm on everything | ±0.005 mm with the machine named |
| Quote turnaround | One week, no questions | Quote plus DFM note in 12 hours |
| Minimum order | 500 pieces to start | No MOQ, one piece to 10,000+ |
| Certification | ISO 9001 only | ISO 9001, IATF 16949, ISO 13485 |
| Inspection | Sample check | 100% inspection, reports on request |
| Shipping window | 4–6 weeks, vague | Parts ship in 3–5 days |
Why a NZ CNC processing service is judged on tolerance first
Every conversation about a NZ CNC processing service starts with the tolerance block on your drawing. That number decides which machines can bid the job. A shop running 27 three-axis machines can hold ±0.05 mm all day. Holding ±0.005 mm is a different problem, and it is mostly about heat, fixturing and metrology.
On a part that is 200 mm long in aluminium 6061-T6, a 5 °C swing in the shop moves the material about 0.02 mm. That is four times your whole tolerance band. This is why shops that quote tight work run temperature-controlled rooms and let parts cool before final inspection. If a supplier cannot explain how they control heat, the tolerance number on their website means little.
Ask which machine will run your part. GreatLight runs 16 simultaneous 5-axis machining centers, 12 four-axis mills, 16 mill-turn centers and 27 three-axis machines among 127 high-precision CNC machines. The largest travel is 4,000 × 400 × 150 mm, and the rotary table is Ø400 mm. A part that fits in 500 × 500 × 450 mm does not need the same setup as a 4,000 mm frame.
One more thing. Tolerance and surface finish travel together. A finishing pass at Ra 0.2–0.8 μm takes a light depth of cut and a fresh tool. If your drawing calls for both a tight bore and a mirror finish, expect a separate finishing operation and a longer cycle. Suppliers who quote it as one operation usually miss one of the two.
Lead time: what 12 hours and 3–5 days actually cover
Lead time gets quoted loosely. Break it into four stages before you compare shops: quotation, DFM feedback, material and setup, and machining plus inspection. A quote that says four weeks without breaking it down tells you nothing about where the risk sits.
GreatLight returns a quotation and a free DFM analysis within 12 hours. Production can start within 24 hours once the drawing and material are confirmed. Parts ship in 3–5 days for typical runs. Those numbers assume standard materials in stock. A titanium TC4 part or an Inconel housing needs a material order first, and that adds days you should plan for.
Ask what the shop does when a feature is unmachinable. A good DFM note says the 0.5 mm internal corner needs a 0.5 mm cutter, which limits depth to about 3 mm, and suggests a 1 mm corner radius instead. That exchange costs a day and saves a scrapped batch.
Historical late delivery at GreatLight sits below 2%. Treat that as a shop-floor number, not a promise. The useful question is what happens on the 2%: who pays for expedited freight, and who owns the rework if the part is already at your dock.
MOQ, materials and finishes that decide the real price
Minimum order quantity is where a NZ CNC processing service either fits your program or does not. If you are a New Zealand product team building three prototypes before a tooling decision, a 500-piece MOQ is a dead end. GreatLight has no minimum order quantity and runs from one prototype to 10,000+ part runs.
Material choice drives cost more than machine time on small jobs. Aluminium 6061 and 6063 machine fast and hold tolerance well. Stainless 304 and 316 work-harden, so feeds and speeds need to be right or the tool rubs. Titanium TC4 and Inconel are slower again, and 17-4PH needs a heat-treat decision before machining, not after.
Finishes add a second supplier and a second lead time. Anodizing, electroless nickel, zinc and silver plating, powder coating, black oxide, bead blasting and polishing are all common. Laser marking needs a minimum character height of 1.5 mm, so a 0.8 mm part number will not survive the mark. Decide the finish before you approve the drawing.
Ask whether finishing is in-house or subcontracted. Subcontracted anodizing adds a transport leg and a queue you cannot see. It also means one more party touching a part that already passed inspection.
Certifications, inspection and the paperwork you should expect
Certificates matter when your customer audits you. ISO 9001:2015 is the baseline for general machining. IATF 16949:2016 adds the automotive traceability and PPAP habits that tier-one buyers expect. ISO 13485:2016 covers medical device work. ISO 27001:2022 covers information security, which matters when you send CAD files across borders.
Read the certificate scope, not just the logo. A certificate that covers machining but not surface treatment does not cover your anodized part. Ask for the scope statement and the expiry date, and check the registrar.
Inspection is the other half. GreatLight inspects 100% of parts before shipment, with a raw material check, in-process monitoring and a final inspection. Reports are available on request. If your drawing has a critical bore, ask for the CMM report for that feature, not a generic certificate of conformance.
Confidentiality belongs here too. Uploads are treated as secure and confidential, and an NDA is available on request. For a New Zealand buyer sending proprietary geometry offshore, the NDA and the ISO 27001 scope together answer the question your legal team will ask.
Industry fit: aerospace, automotive, medical, robotics
A shop that does good work in one industry may be a poor fit in another. The difference is rarely the machine. It is the documentation, the material handling and the tolerance culture.
Aerospace work leans on thin-wall aluminium and titanium parts, tight true position and full traceability. Automotive and EV work leans on repeatability across thousands of parts, with gauges and fixtures built for the volume. Medical device work adds cleaning, passivation and a paper trail that survives an audit years later.
Robotics, electronics, industrial machinery and new energy each have their own habits. A robot arm housing is a stiffness problem. A heat sink is a flatness and finish problem. A battery pack component is a flatness problem at a size that may need the 4,000 mm travel machine.
Send two or three representative parts, not your hardest one. A supplier who prices your typical work fairly is more useful than one who wins the quote with a heroic part and loses money on the rest.
How to read a quote from a NZ CNC processing service
Quotes are hard to compare because shops bundle different things. Ask for the same four lines from every supplier: machining time, material, finishing and inspection. A quote with one lump sum hides where the cost sits and makes negotiation blind.
Watch for missing setup charges. A five-axis job may need one setup while the same part on a three-axis machine needs four, and four setups mean four chances to lose datum. If a quote looks 30% cheaper than the others, the gap is usually setup, inspection or finishing, not machining speed.
Check the currency, the Incoterm and who pays duty into New Zealand. A price in USD with ex-works terms is not comparable to a delivered price. Ask for both, then compare.
Finally, ask for a sample before a production run. GreatLight runs a sample center for exactly this. A sample costs less than a scrapped batch and tells you more about a shop than any catalogue.
Step by step: qualifying a supplier in one week
Run these six steps in order. Each one filters out shops before you spend engineering time.
- 1Send a drawing with the tolerance block intactInclude material, finish, quantity and the critical features you will measure. Do not send a STEP file alone; the tolerance callouts are the job.
- 2Score the DFM replyA strong reply names the machine, flags any feature under 1 mm, and suggests a fix. A weak reply only restates the price.
- 3Ask for the certificate scopeRequest ISO 9001, IATF 16949, ISO 13485 or ISO 27001 scope statements with expiry dates, matched to your industry.
- 4Confirm the inspection planAsk which features get a CMM report and whether 100% inspection applies. Get it in writing before the order.
- 5Place a sample orderOne or two parts, full finish, full inspection. Measure them yourself against the drawing.
- 6Lock the production termsAgree currency, Incoterm, packing and the response time if a part is out of tolerance. Then release the run.
Common questions
Can a NZ CNC processing service hold ±0.005 mm on a 300 mm part?
It depends on material and geometry more than on the machine. Aluminium 6061-T6 at 300 mm will move with temperature, so the shop needs a controlled room and a cool-down before final measurement.
On thin walls or long unsupported sections, ±0.005 mm is realistic only with light finishing passes and stress-relieved stock. Ask what the shop does about residual stress before quoting the tolerance.
What does it cost to ship machined parts to New Zealand?
Freight depends on weight, volume and speed, and we do not quote a flat rate. Ask for the Incoterm you want, usually DAP or DDP, so duty and clearance are visible in the number.
For prototypes, air freight is normal. For a 10,000-part run, sea freight changes the landed cost enough that it belongs in the original comparison.
Do I need an NDA before sending CAD files?
If the geometry is proprietary, yes. We treat every upload as secure and confidential, and an NDA is available on request.
ISO 27001:2022 covers our information security management, which is the part your legal team will ask about.
Which materials are stocked and which need ordering?
Common aluminium grades such as 6061, 6063, 6082 and 7075, plus 303, 304 and 316 stainless, are routine. Titanium TC4, Inconel and 17-4PH are usually ordered per job.
Ordering material adds lead time before the first chip is cut. Tell us the material on the first email so the timeline is honest from the start.
Can you run one prototype and then the production batch?
Yes. There is no minimum order quantity, and the same shop runs from one prototype to 10,000+ part runs.
Keeping the prototype and production at one supplier means the fixture and the inspection plan carry over, which usually removes a second round of first-article checks.
How do you handle a part that arrives out of tolerance?
Send the measurement report and photos. We compare them against our final inspection record for that serial or batch.
Then we agree the disposition: rework, remake, or a drawing change if the tolerance was not achievable in the first place. Getting that answer fast matters more than the paperwork.
Send a drawing, get a quote and a DFM note
Upload your files and we will return a quotation with a free DFM analysis within 12 hours. No minimum order quantity.
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.
