Zhuohang Precision Machining FactoryCNC Swiss Turning

CNC Swiss Turning Checklist: Cost & Supplier Items

CNC Swiss Turning Checklist: Cost & Supplier Items — A cost-first checklist for CNC Swiss turning — the cycle time, setup, scrap and supplier-verification items that. Tolerances: ±0.002 mm turning, ±0.003 mm milling — ISO 9001 / IATF 16949 verified.

A cost-first checklist for CNC Swiss turning — the cycle time, setup, scrap and supplier-verification items that separate a competitive quote from a padded one.

The gist
  • ISO 9001:2015 / IATF 16949:2016 / ISO 14001:2015. certificate numbers published and verifiable.
  • Manufacturing to your print: the plant cuts to your design and reports against your drawing.
  • A quote is only as good as the drawing behind it.
  • The four omissions that turn an accurate quote into a revised one.
  • Confirm revision, FAIR scope, and delivery terms in writing before release.

What makes a CNC swiss turning enquiry quotable?

A quote is only as good as the drawing behind it. The gap between a fast quote and an accurate one is almost always a missing tolerance scheme, an unspecified surface finish, or a material callout that names a family rather than a grade.

The five things that change the answer: the 3D model, the 2D drawing with tolerances, the material grade, the quantity (and the anticipated repeat quantity), and any inspection or certification requirement.

Pre-enquiry checklist

These are the items whose absence most often produces a quote that changes after review.

  • 3D model in STEP or IGES, plus a 2D drawing — the drawing carries the tolerances the model does not.
  • Material as a grade, not a family — "stainless" is not a specification; 316L is.
  • Tolerance per feature, not a blanket note. A single tight dimension drives cost more than ten loose ones.
  • Surface finish callouts where they matter, with the standard named (Ra in ISO or ASME).
  • Quantity and expected repeat quantity, these are different numbers and they change the process.

Checklist. Before you release production

Before releasing, these are the items worth confirming in writing.

  • Which drawing revision is being built — in writing, on the order acknowledgement.
  • What the first-article report will contain, and whether it is full inspection or a sample plan.
  • How capability is reported — the index, the stage, and the sigma estimator, named.
  • Who owns an engineering change and how it is documented mid-run.
  • Packaging, duty, and freight responsibility — whether the quote is EXW, FOB, or delivered.

Three things that change the price without changing the part

STAR SR-32JM Type N Swiss-type CNC automatic lathe at Zhuohang Precision Machining Factory, Dongguan, China.

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 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, agreed per feature during quoting.

Which legal entity is actually responsible for the work?

Legally this is Dongguan Zhuohang Ltd, established 2005, Social Credit Code 91441900MA4UWT6X39, operating under the name Zhuohang Precision Machining Factory from No. 8, Shuibian Songyuan Road, Hengli Town, Dongguan, Guangdong, China 523470.

The 18-character code, checked against the National Enterprise Credit Information Publicity System, confirms a real manufacturer. A trading company may hold a business licence as well, but its scope is trading, not manufacturing, and its address is an office rather than a plant.

Depth in the relevant machine family

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 more than 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 re-route rather than queue when a machine is pulled for service. That, not the headline machine, is what protects a delivery date.

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 this shop actually runs

Capability evidence should come as specifics, not slogans. Behind this guide is a 6,800 m2 plant in Dongguan, China running 100+ CNC machines with 100+ staff. The machine list 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). Aimed at 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). Aimed at 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). Aimed at 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). Aimed at shafts, bushings, flanges up to ±0.002 mm.
  • Wire EDM (5+) - Sodick AQ535L (550/350/300 mm travel, ±20° taper, 800 kg workpiece). Aimed at 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: ±0.003 mm CNC milling / ±0.002 mm CNC turning / ±0.002 mm grinding and wire EDM. Capability: Ppk >= 1.67 initial on key characteristics, Cpk >= 1.33 ongoing.

Certificates: ISO 9001:2015 (116024/A/0001/UK/En), IATF 16949:2016 (131941/A/0001/SM/En, with design clause 8.3 excluded, stated openly) and ISO 14001:2015 (116024/B/0001/UK/En), issued to Dongguan Zhuohang Ltd, registration 91441900MA4UWT6X39, founded 2005.

Where we ship: 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 — plus other countries and regions worldwide, shipped from our base in Dongguan, China.

Contact: Felipe Iglesias, [email protected], +86 13126536955.

Get a quote with the cost drivers named

Send your drawing to [email protected] or call +86 13126536955. We will tell you which tolerance or setup is driving the number, not just the number.

Frequently Asked Questions

Is your IATF 16949 certificate valid for design work?

No. The certificate excludes clause 8.3 (product design). The plant is certified to manufacture to your design and to run the associated process controls, not to originate product design.

Do you need both a model and a drawing?

Yes, in practice. The model defines geometry; the drawing defines what has to be true about that geometry. A quote from a model alone leaves the tolerance scheme to assumption, which is where disputes start.

What is a first-article inspection report?

A documented dimensional report on the first part off the process — typically per AIAG PPAP or a customer-defined format. It is the evidence that the process makes the drawing, and it is worth specifying before the order rather than after.

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.

How is material traceability maintained?

Incoming stock is checked against the mill certificate — composition by XRF, hardness where specified — and traceability is held per heat or per batch as the certificate defines it.

Are you a manufacturer or a trading company?

A manufacturer. The registered entity is Dongguan Zhuohang Ltd (No. 91441900MA4UWT6X39), a 6,800 m² facility with 100+ machines and 100+ staff in Dongguan, open to factory visits.

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.

Standards referenced on this page

  • ASTM A582/A582M-12 — Standard Specification for Free-Machining Stainless Steel Bars
  • ASTM B211/B211M-19 — Standard Specification for Aluminum-Alloy Rolled or Cold Finished Bar, Rod, and Wire
  • ISO 9001 — Quality management systems — Requirements