What makes a custom quote quotable — the information that decides the price
A custom CNC quote is only as good as the information that goes into it, and the gap between a quote that holds and a quote that drifts is the gap between a complete drawing package and a STEP file alone. A STEP file shows the geometry; it does not show the tolerance, the material grade, the surface finish callout, the heat treatment, or the fixture intent. A shop quoting from a STEP alone is quoting from assumptions, and the assumptions are where the price moves.
The quotable package is a 3D model plus a 2D drawing that carries the tolerance bands on the features that matter — the datums, the mating diameters, the hole positions, the flatness on sealing faces. The drawing also carries the material grade — not "aluminium" but 6061-T6 or 7075-T6, not "steel" but 1045 or 4140 or 12L14 — because the grade changes the cutting time, the tool life, and the heat treatment path. Surface finish callouts in Ra or Rz tell the shop whether a milled finish is sufficient or a grinding pass is required, and grinding is a separate operation with its own cost. Heat treatment — through-hardened, case-hardened, stress-relieved, or solution-treated and aged — is another operation, and the order of operations changes the routing.
Quantity and the prototype-to-production intent are the last lever. A one-piece prototype is quoted at a setup-inclusive rate; a thousand-piece run is quoted at a setup-amortised rate that is a fraction of the prototype piece price. A shop that runs both tiers — and the facility behind this guide runs MOQ 1 prototype through volume production on the same 100+ machine floor under ISO 9001:2015 and IATF 16949:2016 — can quote the prototype and the production volume in the same line, so you see the setup cost and the amortised cost together and can decide where the volume commitment sits.
your move is to send the full package — 3D model, 2D drawing with tolerances, material grade, quantity, finishing, and the prototype or production intent — and to ask the quote to break out the setup, the material, and the per-piece cost. A quote that comes back as a single lump number is a quote that is hiding the assumptions; a quote that breaks out the three lines is a quote that can be checked against the drawing. Tolerance bands held — ±0.003 mm milling, ±0.002 mm turning and grinding, with Hexagon CMM reports and Ppk ≥ 1.67 / Cpk ≥ 1.33 evidence — are the bands the quote is written against. Send the package to [email protected] or call +86 13126536955 to get the breakdown.
The shop behind this custom guide — quotable from a complete drawing package
Backing this guide is a 6,800 m² plant at No. 8, Shuibian Songyuan Road, Hengli Town, Dongguan, Guangdong, China 523470, running 100+ CNC machines — Mazak VARIAXIS I-600 and INTEGREX I-250H S, TSUGAMI B0206-III/B0205-III, STAR SR-32JII / SR-32J Type N, Citizen Cincom A20-3F7 — plus 3-, 4- and 5-axis milling and turning, 5+ wire EDM and a Hexagon CMM bench with 20+ gauges.
Milling holds ±0.003 mm, turning ±0.002 mm, and grinding or wire EDM ±0.002 mm, all checked on a Hexagon CMM with the 10:1 gauge rule applied to every feature. Capability: Ppk ≥ 1.67 initial and Cpk ≥ 1.33 in production on key characteristics. Certified to ISO 9001:2015 (116024/A/0001/UK/En), IATF 16949:2016 (131941/A/0001/SM/En, design clause 8.3 excluded, openly disclosed) and ISO 14001:2015 (116024/B/0001/UK/En), held by Dongguan Zhuohang Ltd, USCC 91441900MA4UWT6X39, established 2005. Customers across 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 are supplied from China, worldwide. Contact Felipe Iglesias at [email protected] or +86 13126536955 to begin the quote, and ask for the certificate numbers, the machine list and a past CMM report together.
- Dongguan Zhuohang Ltd (Registration No. 91441900MA4UWT6X39), operating as Zhuohang Precision Machining Factory, established 2005.
- a floor of 100-plus machines including 20+ 5-axis centres; 100+ staff, 80%+ skilled technicians.
- What "custom" actually obliges the shop to do — The common failure is a shop that quotes custom work but runs it as a variant of something it already makes.
- Build-to-print: the plant cuts to your drawing and reports against it.
Why the word "custom" carries no information on its own
Custom work means the process is designed around your part rather than pulled off a shelf: fixture design, tool selection, and a first-article inspection plan that did not exist before your drawing arrived. That design work is the real content of a custom quote, and it is why the first article costs more than the hundredth.
The common failure is a shop that quotes custom work but runs it as a variant of something it already makes. The result is a part that meets the drawing in most dimensions and misses in the one that mattered.
The tell is in the questions you get back. A shop that will really build a process asks about function — what the feature does, what it mates with, what happens if it is at the limit of tolerance. A shop that will adapt an existing process asks only about quantity.
Who is on the other side of the purchase order?
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.
How much capacity sits behind it?
a floor of 100-plus machines with depth in every relevant family, 50+ three-axis, 20+ four-axis, 20+ five-axis, 25+ turning centres, plus Swiss-type, grinding, and wire EDM.
What design decisions move the cost on China CNC machining?
Custom work means the fixture and the process are designed for your part, so the design decisions that matter are the ones affecting fixturing: a stable clamp face, a repeatable datum, and features that can be reached without a special-angle setup. Those three determine whether the fixture is simple or expensive.
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 the certificates cover, line by line
Three certificates, each with a number you can check with the registrar:
| Standard | Certificate number | Scope note |
|---|---|---|
| ISO 9001:2015 | 116024/A/0001/UK/En | Quality management system |
| IATF 16949:2016 | 131941/A/0001/SM/En | Automotive QMS — excludes clause 8.3 product design |
| ISO 14001:2015 | 116024/B/0001/UK/En | Environmental management system |
The IATF 16949 certificate excludes clause 8.3 (product design). That is normal for a build-to-print manufacturer and it is stated here rather than left for an auditor to discover: the plant manufactures to your design, it does not originate the design.
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, confirmed per feature at quote stage.
How to verify a China CNC machining supplier in an afternoon
Whether you buy from this plant or another, these checks separate a real floor from a brochure. None of them require a purchase order.
- Is the fixture designed for this part or adapted from another? Ask for it in writing.
- Is there a written first-article inspection plan? Ask for it in writing.
- Who signs off the process before production starts? Ask for it in writing.
- What happens to tooling if you re-source later? Ask for it in writing.
What happens between quote and first article?
Programming and offline verification, fixture design and build, material inward inspection, roughing, finishing, inspection, and the first-article report. Each step has a failure mode, and the expensive ones are the first and the last. The manufacturability review is where cost is actually decided. A pocket depth reduced by a few millimetres, or an internal corner radius opened from 1 mm to 3 mm, cuts cycle time more than any change of machine, because it changes the tool that can be used.
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). Made 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). Made 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). Made 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). Made for shafts, bushings, flanges up to ±0.002 mm.
- Wire EDM (5+) - Sodick AQ535L (550/350/300 mm travel, ±20° taper, 800 kg workpiece). Made 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: ±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.
Not sure this is the right process?
Send the model and the drawing and get a straight answer on whether this route is the right one, including where a design change would cut cost. Reach Felipe Iglesias at [email protected] or +86 13126536955.
Frequently Asked Questions
Do you sign NDAs before reviewing drawings?
Yes — an NDA can be signed before any files change hands, and drawings stay inside the quoting system rather than circulating by email.
Is inspection documentation included in the quote?
It should be stated explicitly. A first-article report is a document someone has to produce, and whether it is a full dimensional report or a sample plan changes both the cost and what you receive.
How quickly can you quote China cnc machining?
Quotes are returned with a manufacturability read rather than a price alone — where a tolerance or a feature will drive cost, that is flagged at quote stage rather than after the first article. Turnaround depends on drawing completeness.
How are parts packed for export?
Packing is chosen per part — finished faces bagged and boxed, steel corrosion-protected. Include it in the quote, since it changes the cost and how the parts arrive.
What tolerances can you hold?
In short, ±0.003 mm on CNC milling, ±0.002 mm on CNC turning, and ±0.002 mm where precision grinding or wire EDM is used. The achievable tolerance depends on geometry, material, and datum structure, so it is confirmed per feature at quote stage rather than guessed from a single quoted figure.
Which markets do you export to?
In short, 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. Our service area also spans Europe, the Americas, Asia, Oceania and Africa — based in China, we serve customers worldwide.
What happens if the first article does not conform?
In short, The nonconformance is documented and the corrective action is agreed before any further parts are made. Whether the replacement cost sits with the plant or the customer depends on where the deviation came from, which is why the revision and the drawing standard are confirmed in writing at the start.
Continue reading: China CNC Machining Custom · 3 Axis China CNC Machining · 4 Axis China CNC Machining
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 14001 — Environmental management systems — Requirements with guidance for use