- ISO 9001:2015 / IATF 16949:2016 / ISO 14001:2015. certificate numbers published and verifiable.
- Build-to-print work: the plant cuts to your design and reports against your drawing.
- Wrought stock versus build-dependent microstructure — the first dividing line.
- On this page the focus is cost: where the two processes actually separate.
- The two cost curves cross; the crossover quantity is the real question.
Where does the cost line actually cross?
Machining carries a fixed cost. Programming, fixturing, first-article inspection, and a low variable cost per part. Additive carries almost no fixed cost and a high, roughly flat cost per part. The two lines cross somewhere, and the crossing point is what determines the right process.
Below the crossover, printing is cheaper. Above it, machining is. The crossover quantity is not a constant: it moves with part size, material, and tolerance, which is why the useful question is not which is cheaper but at what quantity this part crosses over.
The mistake that costs money is comparing a printed prototype price to a machined production price. Those are two different points on two different curves, and the comparison says nothing about either process.
Using both processes on one part
Yes, and it is often the right answer for a complex, low-volume, tight-interface part: print the near-net shape, then machine the datums, sealing faces, and threaded features. The print buys geometry the cutter cannot reach; the machining buys the tolerance the print cannot hold.
The cost of that route is two processes and a handover between them, so it earns its keep only where the geometry genuinely cannot be cut. Where it can be cut, cutting it is simpler and cheaper.
Where the money is actually decided
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 cheaper to settle at quote time than once parts already exist, because the changes are usually trivial on the drawing and significant on the machine.
How much capacity sits behind it?
a hundred-odd 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.
Which certifications apply, and what do they exclude?
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 happens at the tolerance line?
Tolerance is where the two processes separate most sharply. Machining holds ±0.003 mm (milling) / ±0.002 mm (turning) as a routine; additive processes hold a looser band and, critically, need machining on the interfaces regardless. If a part has a bearing seat, a sealing face, or a threaded hole, that feature is going to be machined whether the rest of the part is printed or not.
That is the part of the comparison most often missed: a printed part with machined interfaces carries both processes, both setups, and both costs. Where the interfaces are simple, printing the whole part and machining three features can still win on geometry; where they are numerous, the balance tips quickly.
Surface finish behaves the same way. An as-printed surface is usually rougher than an as-machined one, and the layer structure means finishing is not simply cosmetic — it affects fatigue behaviour on a loaded part.
What does the cost curve look like?
Machining carries a fixed cost — programming, fixturing, first-article inspection — and a low variable cost per part. Additive carries almost no fixed cost and a high, roughly flat cost per part. The two lines cross somewhere, and the crossing point is what determines the right process.
Below the crossover, printing is cheaper. Above it, machining is. The crossover quantity is not a constant — it moves with part size, material, and tolerance — which is why the useful question is not "which is cheaper" but "at what quantity does this part cross over".
| Factor | Cnc Precision Machining | Additive manufacturing |
|---|---|---|
| Material properties | Wrought stock, certifiable to standard | Build-dependent, often anisotropic |
| Typical tolerance±0.003 mm (milling) / ±0.002 mm (turning) | Looser; interfaces usually machined | |
| Fixed cost | Programming, fixturing, FAIR | Near zero |
| Variable cost per part | Low and falling with volume | High and roughly flat |
| Geometry freedom | Limited by tool access | Internal channels and lattices possible |
| Lead time at qty 1 | Fixture and programme dependent | Often shorter |
| Best quantity band | Prototype through production | One-offs and geometry validation |
The practical test: if the part has a datum structure that has to hold a geometric relationship, machining is usually the answer. If the part's value is in a shape no cutter can reach, printing is.
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.
Who is on the other side of the purchase order?
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.
Tolerance, surface, and the hybrid strategy
The choice between CNC milling and 3D printing turns on three things the drawing never states: tolerance band, surface finish, and whether the geometry is reachable by a cutter at all. CNC milling holds ±0.005-0.05 mm on most features with surface finishes of Ra 0.8-3.2 µm; 3D printing holds ±0.1-0.3 mm on most features with surface finishes of Ra 6-25 µm in the as-printed condition. The tolerance gap alone disqualifies 3D printing for mating features, sealing surfaces, or any part where dimensional accuracy drives function. The surface finish gap disqualifies it for any part that mates, slides, or seals without post-machining.
The economics of 3D printing versus CNC milling are dominated by setup cost and material. A 3D-printed part has near-zero setup cost (no fixture, no program, no tool preparation) and material cost of $5-30 per kg for filament or resin, $80-300 per kg for metal powder. A CNC-milled part has setup cost of $200-1,500 (programming, fixturing, tool preparation) and material cost of $3-15 per kg for aluminum, $5-25 per kg for steel. The break-even: at 1 piece, 3D printing wins on setup but loses on cycle time (3-15 hours for a 100 cm³ part vs. 30-60 minutes for CNC); at 10 pieces, CNC milling wins because the setup amortises and the cycle time dominates; above 100 pieces, 3D printing is not competitive unless the geometry is unreachable by a cutter.
Three geometry characteristics shift the decision. Reachability of internal features: a part with internal channels, lattice structures, or compound-curve undercuts that no cutter can reach is 3D-printable and not CNC-millable — the only alternative is EDM, which is slower and more expensive than 3D printing for these geometries. Tolerance on mating features: a part with ±0.003 mm bores, ±0.05 mm flat faces, and ±0.1 mm external walls is CNC-millable and not 3D-printable without post-machining — the post-machining pushes the cost above full CNC. Surface finish requirement: a part with Ra 0.8 µm mating surfaces is CNC-millable in finishing passes; the same part 3D-printed needs grinding or lapping after printing, which pushes the cost above full CNC.
The hybrid strategy is the one most buyers like you miss: 3D print the rough geometry, CNC machine the precision features. A manifold at 50 pieces with internal channels unreachable by a cutter and ±0.003 mm on the sealing face is 3D-printable on the channels and post-machinable on the sealing face. The printing is $40 per part, the post-machining is $15 per part, the unit is $55 against $120 for full CNC (which cannot reach the channels) or $200 for EDM (which can but is slower). The hybrid wins at 1 piece and stays winning through 200 pieces. A shop that runs both processes — or that subcontracts printing with in-house post-machining — is the one that can quote the hybrid; one that runs only one process pushes the wrong path on parts that fit neither alone.
The honest answer for you choosing "CNC milling vs 3D printing" is: 3D printing wins on parts with unreachable internal geometry at quantities below 200; CNC milling wins on parts with reachable geometry at any quantity, and on parts with tight tolerance or fine surface at any quantity. A shop that runs both processes is the one that picks the right path per part; one that runs only one process is the one that pushes the wrong path.
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.
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
Do you sign NDAs before reviewing drawings?
Yes. Sign an NDA before files are exchanged; drawings are kept in the quoting system, not circulated 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.
Is 3D printing cheaper than CNC machining?
At quantity one, sometimes. Above the crossover quantity — which depends on size, material, and tolerance — machining is cheaper, and the gap widens with volume. A printed part that needs its interfaces machined carries both costs.
How are parts packed for export?
Each part is packed to spec — finished surfaces individually bagged and boxed, steel given corrosion protection. Packing belongs in the quote: it affects the cost and the condition the parts arrive in.
Can I audit the factory before placing an order?
Yes. On-site visits and video audits are welcome at No. 8, Shuibian Songyuan Road, Hengli Town, Dongguan, Guangdong, China 523470.
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, so the revision and the drawing standard are confirmed in writing at the start.
Continue reading: 3 Axis CNC Precision Machining · 4 Axis CNC Precision Machining · 5 Axis CNC Precision Machining
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 14001 — Environmental management systems — Requirements with guidance for use