- Manufacturing to your print: the plant cuts to your design and reports against your drawing.
- 6,800 m² across two buildings in Hengli Town, Dongguan — production, inspection, and engineering under one roof.
- Quality control is a process position, not a final inspection gate.
- Incoming verification, in-process control, and a documented first article.
- Capability reported with the index, the stage, and the estimator named.
Quality control as a process position, not a gate
Quality control is usually imagined as a final inspection — someone measuring the part after it is finished. That is the least useful place to put it, because by then the material, the machine time, and the schedule are all spent. The useful positions are earlier: verifying the incoming material, controlling the process while it runs, and documenting the first article before the rest of the batch is made.
The failure mode this avoids is the expensive one: a batch completed to a wrong assumption. Incoming verification catches the wrong grade; in-process control catches the drift; the first article catches the misinterpreted drawing. Final inspection, by contrast, only tells you what you already paid for.
What the instruments can actually see
Twenty-plus inspection instruments sit alongside the machines: CMM for dimensional and true position work, vision and profile instruments for surface and geometry, hardness testers and coating gauges for heat treatment and plating, and XRF for incoming composition.
The rule that governs all of them is that the instrument should resolve roughly a tenth of the tolerance band it is verifying. An instrument that cannot resolve the band cannot honestly verify it, whatever its certificate says.
What design decisions move the cost on CNC precision machining?
Three design decisions drive most of the cost on a machined part: internal corner radii matched to a real cutter diameter, cavity depth kept within about four times the tool diameter, and a general tolerance on every feature that does not mate. Each one changes the tool that can be used, and the tool determines how much material can be removed per minute. Which is why these matter more than any process selection.
This is best raised at the quote stage, not after the first article, because the changes are usually trivial on the drawing and significant on the machine.
What is the certification position?
ISO 9001:2015, IATF 16949:2016 (excluding clause 8.3 product design), and ISO 14001:2015 — each with a certificate number verifiable with the registrar.
What tolerance applies?
±0.003 mm on CNC milling, ±0.002 mm on CNC turning; ±0.002 mm where precision grinding or wire EDM is used, set feature by feature when we quote.
Which legal entity is actually responsible for the work?
The legal entity behind this site is Dongguan Zhuohang Ltd, founded 2005 and registered in China under Social Credit Code 91441900MA4UWT6X39, marketing under the name Zhuohang Precision Machining Factory. Its registered and production address is No. 8, Shuibian Songyuan Road, Hengli Town, Dongguan, Guangdong, China 523470.
Use the National Enterprise Credit Information Publicity System and the 18-character code to verify a Chinese manufacturer. Trading companies can produce a business licence too, yet the scope reads trading rather than manufacturing and the address is an office, not a plant.
The four inspection points
Four points, in order. Incoming: material is checked against the mill certificate. Composition by XRF, hardness where specified, before it is released to the floor. In-process: the operator and the programme hold the dimension while the part is still on the machine. First article: a documented dimensional report before the batch proceeds. Final: the release inspection against the drawing.
The first-article report is the one buyers most often fail to specify. It is the evidence that the process makes the drawing, and whether it is a full dimensional report or a sample plan changes both the cost and what you actually receive.
| Inspection point | What is checked | What it prevents |
|---|---|---|
| Incoming | Mill certificate, composition by XRF, hardness | A wrong grade being cut into finished parts |
| In-process | Dimension and surface while on the machine | Drift becoming scrap |
| First article | Documented dimensional report | A whole batch run to a misinterpreted drawing |
| Final release | Against the drawing and the order | Nonconforming parts shipping |
What capacity sits behind this?
Total machine count is not the question, the question is how many machines sit in the family that makes your part, because that is the queue your part waits in. The floor runs 100+ machines: 50+ three-axis centres for prismatic work, 20+ four-axis, 20+ five-axis, 25+ turning and mill-turn centres, Swiss-type lathes for long slender parts, precision grinding and wire EDM for the tightest features.
The spare capacity in that family is what lets a part shift lanes instead of waiting in a queue when a machine is pulled for service. That, not the headline machine, is what protects a delivery date.
Paperwork, and why it matters
Typically a first-article inspection report, material certificates traceable to the heat or batch, and any special-process documentation the drawing calls for. Heat treatment, plating, or coating records. What is included should be stated in the quote, because a report is a document someone has to produce.
Traceability is held per heat or per batch as the material certificate defines it. Asking for it costs nothing at order stage and is difficult to reconstruct afterwards.
CNC precision quality control — the three-signature discipline
CNC precision quality control runs on a three-signature discipline: the machinist signs the part's traveler (the dimension was cut to the specified tolerance), the inspector signs the FAI report (the dimension was measured at 10:1 gauge-to-tolerance on a calibrated CMM), the quality manager signs the Cpk report (the process is stable and the index meets the threshold). A shop with the three-signature discipline is one whose precision is documented end-to-end; one without is one whose precision is whatever the operator can do. The gauge R&R (per AIAG MSA 4th edition): the gauge's repeatability and reproducibility must be below 10 percent of the tolerance band. The Hexagon CMM at 10:1 meets the threshold on ±0.003 mm features; a caliper does not. The temperature discipline: the inspection room at 20 ±1 °C (aluminum grows 23 µm/m/°C).
The shop: Dongguan Zhuohang Ltd (USCC 91441900MA4UWT6X39, established 2005, 6,800 sqm floor, 100+ staff, 100+ machines, Mazak VARIAXIS I-600, INTEGREX I-250H S, TSUGAMI B0206-III, STAR SR-32J Type N, Citizen Cincom A20-3F7, Hexagon CMM with 10:1, 20 ±1 °C inspection room, ISO 9001:2015 116024/A/0001/UK/En, IATF 16949:2016 131941/A/0001/SM/En, ISO 14001:2015 116024/B/0001/UK/En). Tolerance: ±0.003 mm milling, ±0.002 mm turning, Ppk ≥1.67, Cpk ≥1.33. Contact: Felipe Iglesias, +86 13126536955, [email protected], PT/EN/FR/ES/ZH/JP.
CNC precision quality control — the calibration chain
CNC precision quality control runs on a calibration chain: the CMM is calibrated per ISO 10360 (the CMM calibration standard), the gauge R&R is verified per AIAG MSA 4th edition, the temperature room's HVAC is calibrated per the manufacturer's interval, the hardness tester is calibrated per ASTM E18 (Rockwell), the XRF is calibrated per the manufacturer's interval. A shop that produces the calibration records on request is one whose inspection system is verifiable; one that does not is one whose inspection system is whatever the shop says. Your filter: ask for the CMM's calibration certificate (ISO 10360), the gauge R&R study, the temperature room's HVAC calibration, the hardness tester's calibration, and the XRF's calibration on the RFQ. A shop that produces all five is one whose precision is documented end-to-end; one that produces fewer is one whose precision is whatever the shop chooses.
The shop: Dongguan Zhuohang Ltd (USCC 91441900MA4UWT6X39, established 2005, 6,800 sqm floor, 100+ staff, 100+ machines, Mazak VARIAXIS I-600, INTEGREX I-250H S, TSUGAMI B0206-III, STAR SR-32J Type N, Citizen Cincom A20-3F7, Hexagon CMM with 10:1, 20 ±1 °C, ISO 9001:2015 116024/A/0001/UK/En, IATF 16949:2016 131941/A/0001/SM/En, ISO 14001:2015 116024/B/0001/UK/En). Tolerance: ±0.003 mm milling, ±0.002 mm turning, Ppk ≥1.67, Cpk ≥1.33. Contact: Felipe Iglesias, +86 13126536955, [email protected], PT/EN/FR/ES/ZH/JP.
CNC precision quality control — the three-signature discipline
CNC precision quality control runs on a three-signature discipline: the machinist signs the part's traveler (the dimension was cut to the specified tolerance), the inspector signs the FAI report (the dimension was measured at 10:1 gauge-to-tolerance on a calibrated CMM), the quality manager signs the Cpk report (the process is stable and the index meets the threshold). A shop with the three-signature discipline is one whose precision is documented end-to-end; one without is one whose precision is whatever the operator can do. The gauge R&R (per AIAG MSA 4th edition): the gauge's repeatability and reproducibility must be below 10 percent of the tolerance band. The Hexagon CMM at 10:1 meets the threshold on ±0.003 mm features; a caliper does not.
The shop: Dongguan Zhuohang Ltd (USCC 91441900MA4UWT6X39, established 2005, 6,800 sqm, 100+ staff, 100+ machines, Mazak VARIAXIS I-600, INTEGREX I-250H S, TSUGAMI B0206-III, STAR SR-32J Type N, Citizen Cincom A20-3F7, Hexagon CMM 10:1, 20 ±1 °C, ISO 9001:2015 116024/A/0001/UK/En, IATF 16949:2016 131941/A/0001/SM/En, ISO 14001:2015 116024/B/0001/UK/En). Tolerance ±0.003 mm milling, ±0.002 mm turning, Ppk ≥1.67, Cpk ≥1.33. Felipe Iglesias +86 13126536955 [email protected] PT/EN/FR/ES/ZH/JP.
What this shop actually runs
If you ask for capability evidence, you deserve a specific answer. This facility operates 100+ CNC machines across 6,800 m2 in Dongguan, China, staffed by 100+ people. The machines, listed by category:
- 5-axis machining centres (10+) - Mazak VARIAXIS I-600 (510/910/510 mm travel, 12,000 rpm, 22 kW, 71.6 N·m, 30-tool BT40) and Mazak INTEGREX I-250H S (B-axis 0.0001°, 24 kW, 124 N·m, 38-tool HSK-A63). Intended for compound-angle parts, single-setup multi-face prismatic work, and aerospace fittings where datum transfer loss is unacceptable.
- 3-axis / 4-axis machining centres (50+) - Brother SPEEDIO S500Z2N / S700Z2N (10,000 rpm, 14/21-tool ATC, 0.7 s tool-to-tool, Z-axis 2.2 G) and Mazak VCE-430A L / VCE-570C L (10,000 rpm, 118 N·m, 24-tool ATC). Intended for prismatic parts, plates, brackets, housings.
- Swiss-type turning centres (10+) - Citizen Cincom A20-3F7 (Φ20 mm, 10,000 rpm), TSUGAMI B0206-III / B0205-III (Φ20 mm, 0.1 µm), STAR SR-32JII / SR-32J Type N (Φ32 mm, 8,000 rpm). Intended for long, slender rotational parts at ±0.002 mm.
- CNC turning centres (20+) - HEADMAN T70M/1250 (720 mm swing, 117 mm bore, 3,000 rpm, BMT75 12-station turret). Intended for shafts, bushings, flanges up to ±0.002 mm.
- Wire EDM (5+) - Sodick AQ535L (550/350/300 mm travel, ±20° taper, 800 kg workpiece). Intended for hardened tool steel, internal splines, sharp internal corners that milling cannot reach.
- Inspection: Hexagon CMM + 20+ gauges - Hexagon CMM for coordinate measurement, plus vision system, profilometer, hardness tester, coating thickness gauge, XRF for material verification. The 10:1 rule (gauge 10x more accurate than the band) is applied to every feature.
- Machine highlights - VARIAXIS I-600: one-setup multi-face 5-axis + MAZA-CHECK auto-calibration; INTEGREX I-250H S: DONE-IN-ONE mill-turn, B-axis 0.0001° + Ai thermal shield; SPEEDIO S500Z2N / S700Z2N: Z-axis 2.2 G + 0.7 s ATC; Swiss-type: guide-bush switchable + 0.1 µm resolution.
Tolerance bands: ±0.003 mm milled, ±0.002 mm turned, ±0.002 mm ground or wire-cut. Capability indices: Ppk >= 1.67 at the initial study; Cpk >= 1.33 ongoing in production.
Certifications: ISO 9001:2015 (116024/A/0001/UK/En) · IATF 16949:2016 (131941/A/0001/SM/En, design clause 8.3 excluded) · ISO 14001:2015 (116024/B/0001/UK/En), held by Dongguan Zhuohang Ltd (USCC 91441900MA4UWT6X39, since 2005).
Service area: we supply Austria, Belgium, the Czech Republic, Denmark, France, Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Spain, Sweden and the United Kingdom in Europe; Brazil, Canada, Mexico and the United States in the Americas; China, Israel, Japan, Singapore and Sri Lanka in Asia; Australia and New Zealand in Oceania; and South Africa in Africa, with worldwide delivery from China.
Contact: Felipe Iglesias, [email protected], +86 13126536955.
Send a drawing and get a manufacturability read
Upload your model for a quote, or arrange a factory audit with [email protected] or +86 13126536955. Ask for Felipe Iglesias.
Frequently Asked Questions
What materials do you machine?
Aluminum, stainless steel, titanium, brass, copper, and Inconel for metals; PEEK and Delrin (POM) for plastics. Material certificates are verified on incoming stock.
How is an engineering change handled mid-production?
The change is documented against a revision, the affected parts in process are identified, and the revised drawing is confirmed in writing before work restarts. The important part is that the revision in force at any moment is a single, written one.
What quality documentation comes with cnc precision machining orders?
A first-article inspection report, material certificates traceable to heat or batch, and any special-process records the drawing requires. Whether the FAIR is a full dimensional report or a sample plan should be stated in the quote.
Can you work to ASME Y14.5 as well as ISO?
Yes. Both geometric dimensioning conventions are used. The important thing is that the drawing states which one applies, because the same symbol can mean different things under the two standards.
Do you hold stock or consignment for repeat orders?
On repeat orders, a forecast lets the shop hold material and, where justified, dedicated fixturing in readiness. It is a commercial arrangement rather than a standard term, worth raising at order two rather than order one.
Is your IATF 16949 certificate valid for design work?
No — clause 8.3 (product design) is excluded. The certification covers manufacturing to your design and the associated process controls, not originating design.
What files do you need for a quote?
Send a 3D model (STEP or IGES) plus a 2D drawing that names the tolerances, surface finishes, material spec and any inspection or certification needs. The drawing is the contract; the model alone typically leaves the tolerance scheme open.
Standards referenced on this page
- ASTM B211/B211M-19 — Standard Specification for Aluminum-Alloy Rolled or Cold Finished Bar, Rod, and Wire
- ASTM A582/A582M-12 — Standard Specification for Free-Machining Stainless Steel Bars
- ISO 9001 — Quality management systems — Requirements