UK NZ CNC Factory: 6 Checks Before You Order

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  Key takeaways
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  What a UK NZ CNC factory quote should show
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  Match tolerance to the features that matter
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  Read lead time as queue plus machining
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  MOQ, tooling and the prototype-to-production jump
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  Certifications and inspection paperwork
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  How to compare two quotes fairly
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  Materials and part size: where a shop stops being a fit
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  Step by step: qualifying a supplier in one week

Every drawing has a few features that carry the function and a long list that just needs to be close. A UK NZ CNC factory that quotes a single blanket tolerance is either overpricing the job or quietly loosening the loose dimensions. Ask which features will be held at ±0.005 mm and which will run at general machining tolerance.

±0.005 mm is a real number, not a marketing phrase. Reaching it on a 100 mm aluminium bore is a different problem from reaching it on a 300 mm steel plate, because thermal growth and tool deflection scale with size. A shop that can explain that difference is a shop that measures its parts.

Surface finish follows the same logic. Ra 0.8–1.6 μm is a normal turned or milled finish. Ra 0.2–0.8 μm usually needs a second operation, a finer tool or a polishing step, and that shows up in the price. Specify finish only where a seal, bearing or optical surface needs it.

One more thing to settle early: datum choice. If the drawing datums do not match how the part sits in the fixture, the shop will pick its own datums and the inspection report will disagree with your CMM program. Send the datum scheme with the model.

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  Tight-tolerance featuresList them explicitly so setup and inspection time is priced correctly.
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  General featuresLeave them at standard tolerance and save the money.
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  Finish calloutsRa 1.6–3.2 μm as machined, Ra 0.8–1.6 μm when a mating surface needs it.
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  Datum schemeAgree it before the first chip, not after the first reject.

A 40 mm aluminium bracket takes minutes to cut. The reason a quote says three weeks is that the machine is booked, the material has to arrive and the part has to pass inspection. When you compare two UK NZ CNC factory options, ask what part of the lead time is queue and what part is process.

Material is the usual hidden delay. 6061-T6 plate is stocked almost everywhere. A specific titanium grade or a 17-4PH bar in an odd diameter may not be. If the shop quotes a short lead time without checking stock, that date will move.

Setup count drives the calendar more than cycle time. A part that needs four sides machined on a three-axis mill is four setups. The same part on a 5-axis center is one setup, so the machine is free sooner. That is where the 16 simultaneous 5-axis centers in our floor plan change the schedule.

Finally, treat inspection as part of lead time. A first article with a full dimensional report can add a day. If you need parts in 3–5 days, say so on the RFQ and let the shop plan inspection around it.

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  Ask the splitQueue days vs. machining days. A vague answer usually means a moving date.
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  Check the materialConfirm the exact grade and stock form before you accept the date.
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  Count setupsFour setups is a different schedule from one, even with the same cycle time.
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  Plan inspectionFirst article reports take time. Say whether you need one.

A minimum order quantity is usually a tooling decision in disguise. CNC machining does not need a mold, so a shop asking for 50 pieces minimum is protecting setup time, not covering a die. That is a pricing habit, not a technical limit.

For prototype work, no minimum order quantity matters more than unit price. You want one part to test fit and function, then a small batch to run in your own assembly, then a production run. If the first step is blocked by a 50-piece order, you pay for parts you will throw away.

The jump from prototype to production should not change the process. If the prototype comes off a 5-axis center and the production run comes off the same center with the same fixtures, the second batch matches the first. Switching process, supplier or machine between phases is where dimensions drift.

Ask one question: can the same shop quote 1 piece and 10,000 pieces on one sheet? If the answer is yes, the process is stable and the pricing is transparent. If the two quotes come from different departments with different tolerances, expect a gap.

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  No MOQOne prototype to 10,000+ part runs from the same process.
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  Same fixturesPrototype and production should share setup so dimensions carry over.
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  Batch sizeAsk what batch size keeps the price flat. Small batches often cost the same as mid batches.

Certificates tell you what system the shop runs, not what your part will measure. ISO 9001:2015 covers general quality management. IATF 16949:2016 is the automotive standard and brings traceability and PPAP-style discipline. ISO 13485:2016 applies to medical devices. ISO 27001:2022 covers information security, which matters when your drawings are confidential.

The useful question is not "are you certified" but "which certificate applies to my part". A medical housing and a robot arm bracket do not need the same paperwork. Our four certificates sit on the wall for a reason: they cover the industries we actually serve, including aerospace, automotive and EV, medical devices, robotics and industrial machinery.

Inspection is where certificates become real. 100% inspection before shipment, with raw material check, in-process monitoring and final inspection, is the baseline. Reports are available on request. Ask for the report format before you order, because a CMM report on the wrong datums is just paper.

For regulated work, ask how material certificates are traced. A 316L stainless part for a medical device needs the mill certificate tied to the heat number, not a generic statement that the material is stainless.

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  Match the standardISO 9001 general, IATF 16949 automotive, ISO 13485 medical.
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  Information securityISO 27001:2022 matters when the design itself is sensitive.
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  ReportsAsk for the inspection format up front and send your CMM program.
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  Material traceabilityHeat numbers and mill certificates for regulated parts.

Two quotes for the same part often differ by 30% or more, and the difference is rarely the hourly rate. It is what each shop included. One quote has material, machining and shipping. The other has material, machining, deburring, anodizing, laser marking and inspection. Compare the line items, not the totals.

Finishing is the most common gap. Anodizing, electroless nickel, powder coating and bead blasting are separate operations with separate lead times. If one quote says "finished part" and the other lists five finishing steps, the cheap quote is probably unfinished.

Freight and packaging also hide. A 4,000 mm part needs crating. Small precision parts need foam and individual wrapping. Ask how parts ship and who pays, and read the Incoterms on the quote rather than assuming.

Then look at what happens when something goes wrong. A shop that offers DFM analysis within 12 hours and starts production within 24 hours is set up to catch a drawing problem before cutting metal. That is worth more than a few percent off the unit price.

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  Line by lineMaterial, setup, machining, finishing, inspection, freight.
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  Finishing scopeConfirm which finish, which color and which masking.
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  Shipping termsCrating for long parts, Incoterms stated on the quote.
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  DFM feedbackFree analysis within 12 hours is a signal of an engineering-led shop.

A UK NZ CNC factory is not the right partner for every part. Knowing the edges saves a wasted RFQ. On materials, the common metals are covered: aluminium 6061, 7075 and 6082, stainless 303, 304, 316L and 17-4PH, steels 1018 through 4340 and tool steel, copper alloys from C101 to C36000, titanium TC4 and Inconel, plus engineering plastics from POM to PEEK.

Size is the harder limit. Our largest travel is 4,000 × 400 × 150 mm, which suits long rails, beams and extrusion profiles. Medium work runs on 750 × 1,150 × 550 mm and 600 × 600 × 600 mm machines. Compact parts use 500 × 500 × 450 mm and 500 × 310 × 200 mm centers with a Ø400 mm rotary table for turned and milled features in one setup.

If your part is a large casting with deep internal pockets, or a thin-wall part that will move during machining, say so in the RFQ. Those jobs need a different setup plan and sometimes a stress-relief step before finishing.

This is also where a shop should tell you no. If a feature needs a tolerance the process cannot hold, or a geometry that needs a fixture you have not budgeted for, a good supplier says it before the order, not after the first article.

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  Large travel4,000 × 400 × 150 mm for long parts.
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  Mid-size750 × 1,150 × 550 mm and 600 × 600 × 600 mm.
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  Compact and rotary500 mm class machines plus a Ø400 mm rotary table.
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  Ask earlyThin walls, deep pockets and hard alloys change the plan.