Supplier Spotlight: Bach Tung Co., Ltd. — Dual CMM + VMM Inspection, CNC Milling, Turning & Laser Engraving in Vietnam
April 6, 2026 · 10 min read
Part of our Supplier Spotlight series — real factory visits, real photos, no stock images.
US procurement managers sourcing precision machined components from China face a compounding problem in 2026: not only does Section 301 add 25% to their landed cost on the vast majority of CNC machined parts, but many China-based factories lack the metrology infrastructure to support rigorous dimensional inspection documentation — the kind required for FAI/PPAP qualification or CMM-backed GD&T validation.
This is Supplier Spotlight #15 in our ongoing series — real site visits, real photos, no anonymous network entries, no stock images. Today's factory: Bach Tung Co., Ltd. — a Vietnam-based CNC precision machining factory with an unusually strong metrology suite including both a 3D CMM and a 2D Video Measuring Machine (VMM) in-house, plus a flatness meter, structured defective goods segregation, laser engraving, CNC milling, and CNC turning capabilities.
Previous spotlights: Bueno Technology (CNC), Altop (Die Casting), NAPEC (CNC + CMM), HDP (CNC + VMM), Minh Quang (Multi-Process), Eguchiseiko (Die Casting), Hirata (Japanese Machining), Huynh Duc (CNC + CMM), Lidovit (Fasteners), Ming Chuan (Injection Molding), Lac Hao (Multi-Process), Kinzoku (Die Casting + CMM), Kobayashi Casting (Investment Casting), Shin Yi Valves (Valves & Fittings).
⚠️ Section 301 Tariff Alert — HTS Chapter 84 (CNC Machined Components)
US importers pay a 25% Section 301 tariff on precision machined components sourced from China (HTS Ch.84). On a $600K annual CNC machined parts program from China, that adds est. $150K in annual tariff exposure on top of standard MFN duties. Vietnam-origin goods carry $0 Section 301 surcharge. Standard MFN duty on machined parts: 2–4.5% depending on subheading.
Why Dual Metrology (3D CMM + 2D VMM) is a Rare Qualification Signal
In our 50-point Dolphin Audit, Pillar 3 — Quality Systems — is where most factories at this scale stumble. Hand gauges are universal. A 2D Video Measuring Machine (VMM) is common in better-equipped shops. A 3D Coordinate Measuring Machine (CMM) starts to separate serious factories from the pack. Having both, plus a flatness meter, in a Vietnam CNC machining factory of this size is genuinely uncommon.
Here's why that matters practically for US buyers:
- 3D CMM generates traceable, digital dimensional reports for GD&T callouts — position, concentricity, runout, true position — required for FAI (First Article Inspection) documentation and PPAP submission at Levels 2–5.
- 2D VMM handles fast, non-contact measurement of 2D profile features — contours, hole patterns, thread pitch, edge geometry — without the setup time of a CMM probe program. Ideal for 100% inspection of critical features at volume.
- Flatness meter addresses the specific requirement of mating surface flatness — critical for gasketed interfaces, precision fixtures, sealing surfaces, and any assembly requiring repeatable contact.
The combination means Bach Tung can support different documentation requirements across different buyer programs: CMM-backed FAI reports for automotive-tier programs, VMM records for fast-cycle production inspection, and flatness validation for structural and hydraulic components. This is not a single-tool shop retrofitting a measurement station — it's a factory that has invested in complementary metrology.
Factory at a Glance
Country
Vietnam
Factory Type
CNC Precision Machining (Multi-Process)
Processes Verified On-Site
CNC Milling, CNC Turning, Laser Engraving
Inspection Equipment
3D CMM + 2D VMM + Flatness Meter
Quality System Feature
Dedicated Defective Goods Segregation Area
Factory Photos in DEWIN Network
8 real factory photos
Dolphin Audit Status
Verified — 50-point audit completed
HTS Classification (US Import)
Ch.84 — machinery parts & precision components
Section 301 (China source)
+25% surcharge
Section 301 (Vietnam source)
$0 — Not applicable
The Metrology Suite — Photo by Photo
3D CMM and 2D VMM in Bach Tung's dedicated inspection zone — enabling both contact dimensional reporting and non-contact profile measurement.
Flatness meter — used for mating surface validation, sealing face inspection, and structural component flatness verification.
Dedicated defective goods area — a core quality system requirement. Segregated non-conforming parts prevent mixing with good stock and enable root cause traceability.
What a Defective Goods Area Tells You About a Factory's Quality System
One of the most revealing signals in our 50-point Dolphin Audit isn't the most expensive piece of equipment — it's whether a factory has a defined, physically labeled area for segregating non-conforming parts. Bach Tung has one.
Here's what this indicates:
- Non-conforming parts are identified and physically separated from conforming stock — preventing accidental shipment of defective product.
- The factory has a documented non-conformance process: identification → segregation → root cause analysis → disposition (scrap, rework, return). This is required for PPAP Levels 3–5.
- Inspection results are actioned, not just recorded. A factory that measures but doesn't segregate is only half-way there.
- The practice reflects a quality management culture where floor operators are empowered to flag issues rather than pass them downstream.
For US buyers auditing Vietnam factories for the first time, this is a quick visual screening question: "Show me your defective goods area." The answer tells you whether quality outcomes are systematically managed — or treated as optional.
Production Capabilities — Verified On-Site
CNC milling and CNC turning machines — verified on-site during Dolphin Audit visit.
Laser engraving capability — supports part marking for lot traceability, serialization, and customer-specific identification requirements.
Laser Engraving as a Traceability Asset
In-house laser engraving is more than a cosmetic service. For US buyers managing complex supply chains, laser-marked parts serve several critical functions:
- Lot traceability: Production batch codes, date codes, or serial numbers are permanently marked, enabling field service teams to trace a component back to its manufacturing run if a quality issue surfaces after delivery.
- Country of Origin (COO) compliance: CBP requires Vietnam-origin goods to be marked with "Made in Vietnam" when imported into the US. In-house laser marking means the factory can apply COO marks directly — no secondary operation, no outsourcing dependency.
- Part identification for assembly: Multi-variant programs (e.g., same geometry, different material grades or tolerance classes) can be serialized at the factory to prevent mix-up downstream.
- Customer branding: OEM part numbers, brand logos, and specification callouts marked directly on components — supporting white-label or private-label programs.
Finished Products
Finished precision machined components from Bach Tung's production floor.
Section 301 Tariff Impact — CNC Machined Parts from China vs Vietnam
| HTS Subheading | Description | China: MFN + S301 | Vietnam: MFN Only |
|---|---|---|---|
| 8466.10 | Tool holders & self-opening dieheads | 4.5% + 25% = 29.5% | 4.5% |
| 8484.10 | Gaskets / sealing components | 3.5% + 25% = 28.5% | 3.5% |
| 8483.30 | Bearing housings without bearings | 4.5% + 25% = 29.5% | 4.5% |
| 8483.90 | Parts of transmission shafts & cranks | 4.5% + 25% = 29.5% | 4.5% |
| 8462.10 | Forging/stamping presses (machined) | 4.4% + 25% = 29.4% | 4.4% |
| 8487.90 | Machinery parts NEC | 3.9% + 25% = 28.9% | 3.9% |
Source: USTR Section 301 tariff actions (Trade Act of 1974); MFN rates per USITC HTS database. Section 301 applies to China-origin goods only. Vietnam-origin goods at $0 Section 301. Verify exact subheading classification for your program.
Est. Landed Cost Comparison — $600K China CNC Program
China (CNC Parts, HTS Ch.84)
Vietnam (Bach Tung, $0 S301)
Est. annual saving: approx. $216K on this program. Figures are illustrative estimates. Ex-factory pricing varies by geometry, material, and tolerance requirements. Soft language per accuracy protocol.
Part Fit Matrix — What Bach Tung Is Best Suited For
| Part Type | Process Fit | Inspection Support | Fit Score |
|---|---|---|---|
| Precision shafts & turned components | CNC Turning | CMM runout/concentricity + VMM diameter | ✅ Excellent |
| Milled housings, brackets, fixtures | CNC Milling | CMM positional GD&T + flatness meter | ✅ Excellent |
| Sealing surfaces / gasketed interfaces | CNC Milling + Flatness | Flatness meter directly applicable | ✅ Excellent |
| Serialized / lot-traced components | Any + Laser Engraving | Laser marking for COO + traceability | ✅ Excellent |
| FAI / PPAP-required programs | Any CNC process | CMM dimensional report + defective goods documentation | ✅ Strong |
| Complex 5-axis prismatic parts | Verify machining centers | CMM support available | ⚠️ Discuss with Dewin |
| Large structural weldments | Outside scope | — | ❌ Not applicable |
50-Point Dolphin Audit — Bach Tung Results
| Pillar | What We Verified On-Site | Result |
|---|---|---|
| 1. Facility & Safety | Workshop layout, fire safety, housekeeping, organized material flow | ✅ Pass |
| 2. Equipment & Capacity | CNC milling, CNC turning, laser engraving — all verified operational on-site | ✅ Pass |
| 3. Quality Systems | 3D CMM + 2D VMM + flatness meter + dedicated defective goods segregation area — above average for factory scale | ✅ Pass — Strong |
| 4. Workforce & Management | Organized production floor, active inspection culture evidenced by defective goods system | ✅ Pass |
| 5. Export Compliance | Laser engraving supports COO marking; Vietnam-origin goods comply with Section 301 anti-circumvention requirements when genuine manufacturing value-add is verified | ✅ Pass |
Dewin vs Unverified Sourcing — 6-Factor Comparison
| Factor | Dewin (Bach Tung) | Trade Show / Directory Sourcing |
|---|---|---|
| Factory inspection evidence | 8 real photos from on-site audit visit | Self-reported capability claim |
| Metrology verified? | ✅ CMM + VMM + flatness meter confirmed on-site | ❌ Unknown — buyer must verify independently |
| FAI/PPAP documentation support | ✅ CMM-backed dimensional reports available | ⚠️ Inconsistent — depends on factory |
| Section 301 tariff status | $0 — Vietnam origin, $0 Section 301 | Unverified origin risk |
| COO documentation for CBP | ✅ Dewin manages COO + laser marking | ⚠️ Buyer must manage independently |
| Non-conformance management | ✅ Defective goods area confirms active system | ❌ Unknown — high variability |
How to Source from Bach Tung Through Dewin
Submit Your RFQ
Upload your drawings, specs, material requirements, and target quantities via our instant quote form. Include any FAI/PPAP documentation requirements.
Factory Match & Review
Dewin matches your program to Bach Tung based on process fit, tolerance requirements, and required inspection documentation. We share the Dolphin Audit summary.
Sample Production
Bach Tung produces first articles. Dewin's on-ground team conducts FAI — including CMM dimensional report, material cert verification, and visual inspection.
COO & Documentation
Dewin coordinates Certificate of Origin documentation and laser engraving for COO marking where required by CBP. Section 301 compliance is built into the process.
Production Monitoring
On-ground pre-shipment inspection before each production run ships. Non-conforming parts are caught before they leave the factory — not after customs.
Continuous Program Management
Dewin manages ongoing communication, quality records, and re-audit scheduling. You get a dedicated account contact, not a ticketing system.
Frequently Asked Questions
What types of machined parts is Bach Tung best suited to produce?
Bach Tung is well-suited for precision turned components (shafts, bushings, fittings), CNC milled housings and brackets, and components requiring laser engraved markings or COO identification. Their dual CMM + VMM metrology suite makes them strong for FAI and PPAP-required programs where dimensional reporting is critical.
Does Bach Tung support FAI and PPAP documentation?
Yes. The presence of a 3D CMM enables CMM-backed dimensional reports for First Article Inspection submissions. Bach Tung's defective goods segregation system also demonstrates the process discipline required for PPAP Level 3 and above. Dewin coordinates FAI management as part of our standard onboarding process.
Is Vietnam manufacturing really cheaper than China for CNC machined parts?
In total landed cost terms, yes — in many cases significantly so. Ex-factory pricing is competitive with China for most CNC machined components. When you add the 25% Section 301 tariff on China-origin goods, the total landed cost differential becomes substantial. Our est. comparison on a $600K CNC program shows approx. $216K in annual landed cost savings, though actual savings depend on specific part geometry, material, and quantities.
How does Dolphin Audit quality compare to ISO 9001?
ISO 9001 is a process framework certification — it confirms a quality management system exists, but doesn't score factory equipment, verify specific machines on-site, or assess inspection capability directly. Dewin's 50-point Dolphin Audit physically visits and scores 50 criteria across 5 pillars including equipment verification, inspection tool confirmation, and export compliance review. For US buyers, the Dolphin Audit provides actionable sourcing intelligence beyond what an ISO certificate conveys.
Can I source from Bach Tung if I'm not yet importing from Vietnam?
Absolutely — that's exactly who Dewin is built for. We handle factory match, RFQ management, sample coordination, on-ground FAI, COO documentation, pre-shipment inspection, and freight coordination. You don't need an existing Vietnam supply chain to access Bach Tung through Dewin. Submit your RFQ and we'll manage the rest.
Source from Bach Tung — $0 Section 301, Full CMM Documentation
Submit your RFQ and we'll send you a Dolphin Audit summary, factory photos, and est. landed cost comparison within 2 business days.