Supplier Spotlight #26: Tho Thanh Phat Die Casting Company
Integrated die casting + CNC milling + CNC lathe + in-house 3D CMM coordinate measuring machine — all verified on-site by Dewin's audit team in Vietnam. Full Dolphin Audit completed. FAI, PPAP, and GD&T documentation capability confirmed.
Tho Thanh Phat Die Casting Company — Workshop Overview. Photo taken by Dewin on-ground audit team.
Factory Overview — Tho Thanh Phat Die Casting Company
Tho Thanh Phat Die Casting Company is a Vietnam-based precision manufacturer running a complete integrated manufacturing cell: die casting → CNC milling → CNC lathe → 3D CMM inspection. Dewin's on-ground audit team completed the full 50-point Dolphin Audit, physically verifying all four capabilities.
What sets this factory apart in Vietnam's die casting sector: the presence of an in-house 3D CMM. Most die casting factories outsource CMM measurement to third-party labs — adding cost, lead time, and a gap in the quality chain between casting and machining inspection. Tho Thanh Phat keeps the full process loop in-house.
This factory is well-suited for global buyers who need documentation-intensive sourcing programs — automotive buyers requiring PPAP packages, industrial OEMs needing FAI dimensional reports, or procurement teams building long-term supplier relationships based on verifiable quality data.
Factory Quick Facts
Real Factory Photos — Taken by Dewin Audit Team
Factory exterior — Tho Thanh Phat Die Casting Company
Workshop overview — integrated production floor
CNC milling machine — post-cast machining operations
CNC lathe machine + inspection area — turning and QC zone
3D CMM coordinate measuring machine — in-house GD&T inspection
Finished die cast + machined products — completed parts
All photos taken by Dewin's on-ground audit team during factory visit. No stock photography.
🔬 Dolphin Audit: Pillar 2 — Equipment Verification
Dewin's on-ground auditors physically confirmed the 3D CMM coordinate measuring machine at Tho Thanh Phat — verified as operational and in active use during the audit visit. This is the most critical capability gap between this factory and typical die casting suppliers in Vietnam.
What a 3D CMM Enables for Die Casting Quality
Full GD&T Measurement
True position, flatness, perpendicularity, profile, runout — all GD&T callouts on your drawing can be measured and documented. Hand gauges cannot do this.
FAI Dimensional Report
First Article Inspection with every critical dimension measured, documented, and reported against your drawing tolerances. Standard requirement for industrial and automotive OEM buyers.
PPAP Level 2–3 Data
Dimensional measurement data, Cpk process capability studies, and dimensional variation analysis — required by automotive Tier 1 buyers, now available from this Vietnam factory.
Inspection Method Comparison for Die Cast Parts
| Inspection Capability | Hand Gauges / Calipers | 2D VMM (Optical) | 3D CMM ✅ (Tho Thanh Phat) |
|---|---|---|---|
| Linear dimensions | ✅ Yes | ✅ Yes | ✅ Yes |
| Complex 3D surface profiles | ❌ No | ⚠️ 2D only | ✅ Full 3D |
| True position (GD&T) | ❌ No | ⚠️ 2D features only | ✅ Full GD&T |
| Internal bore geometry | ⚠️ Bore gauge only | ❌ No | ✅ Probing capability |
| Flatness & parallelism | ❌ No | ❌ No | ✅ Yes |
| FAI full dimensional report | ❌ Not practical | ⚠️ Partial | ✅ Complete |
| PPAP Level 2–3 data | ❌ No | ❌ No | ✅ Yes |
| Statistical Cpk output | ❌ No | ❌ No | ✅ Yes |
50-Point Dolphin Audit Results
What Dewin's on-ground auditors physically verified at Tho Thanh Phat Die Casting Company across all 5 audit pillars:
| Pillar | What Was Verified On-Site | Global Buyer Relevance | Status |
|---|---|---|---|
| Pillar 1 — Facility & Safety | Production floor organization, safety practices, casting area → machining → inspection zone workflow separation | Disorganized facilities create part mixing, mislabeled shipments, and contamination risks in finished castings | ✅ Verified |
| Pillar 2 — Equipment & Capacity | Die casting machine confirmed operational, CNC milling and lathe verified, 3D CMM confirmed in active use and calibrated | In-house CMM directly enables FAI, PPAP, and ongoing dimensional monitoring without external lab dependency | ✅ Verified (incl. CMM) |
| Pillar 3 — Quality Systems | Inspection records reviewed, CMM report generation process observed, nonconforming part handling assessed | CMM is only valuable if reports are generated and acted upon — auditors verified the complete QC loop | ✅ Verified |
| Pillar 4 — Workforce & Management | CNC operators observed on machines, CMM operator competency assessed, management engagement during audit | GD&T knowledge and CMM operator training directly affect measurement accuracy and report reliability | ✅ Verified |
| Pillar 5 — Export Compliance | VCCI Form B issuance capability, understanding of Vietnam origin rules, anti-circumvention documentation posture | FTA and MFN tariff benefits require a valid Certificate of Origin — this pillar confirms the factory can properly support CO issuance | ✅ Verified |
FTA Tariff Advantages for Global Buyers
Vietnam's 16+ Free Trade Agreements mean buyers from multiple markets benefit from preferential tariff rates on die cast and machined parts. CO form types required per agreement:
CPTPP
Canada, Australia, Japan, NZ, Singapore, Malaysia, Peru, Chile, Mexico
Die cast aluminum (HS 7616): 0% for most members vs MFN rates
CO Form Required:
Form CPTPP
EVFTA
EU-27 member states
Aluminum articles and machinery parts: staged reductions toward 0% for buyers in Germany, France, Italy, Netherlands and others
CO Form Required:
EUR.1 / REX Declaration
RCEP
14 Asia-Pacific nations incl. Japan, South Korea, China, ASEAN
Regional value content rules — enables regional supply chain advantage; die cast parts covered
CO Form Required:
Form RCEP
UKVFTA
United Kingdom
Similar to EVFTA terms for aluminum and machinery; UK buyers source at preferential rates post-Brexit
CO Form Required:
EUR.1 / UK Declaration
FTA benefit rates subject to annual review. Dewin manages Certificate of Origin documentation for all supported FTA markets. Consult a licensed customs broker for program-specific tariff classification and CO eligibility determination.
Integrated Factory vs. Split Supply Chain: What Changes
| Risk Factor | Split: Die Caster + Machining Shop + External CMM Lab | Tho Thanh Phat (All In-House ✅) |
|---|---|---|
| Transfer damage risk | Castings damaged or mixed between factory transport | Zero inter-factory transfers — parts never leave the floor until finished |
| Quality accountability | Casting factory blames machining shop, machining shop blames CMM lab | One factory, one quality record, clear accountability |
| Lead time | Each supplier has own queue — compounds to 8–12 weeks typical | Single production schedule — lead time predictable and shorter |
| CMM availability | Lab booking required — adds 3–7 days per inspection batch | In-house CMM — inspections scheduled within normal production flow |
| COO documentation | Multi-party subcontract trail adds CBP and FTA eligibility complexity | Single factory, clear Vietnam-origin manufacturing chain |
| Dewin audit scope | 3 separate site visits and 3 Dolphin Audits required | One 50-point Dolphin Audit covers all processes at one factory |
Sourcing Through Dewin vs Alternatives
| Factor | Dewin (Tho Thanh Phat) | Alibaba Direct | Trade Fair / Sourcing Agent |
|---|---|---|---|
| Factory physical audit | ✅ 50-point Dolphin Audit | ❌ No physical audit | ❌ No standardized audit |
| 3D CMM verified in-house | ✅ Physically confirmed operational | ❌ Claimed only | ❌ Unknown |
| CMM calibration records checked | ✅ Auditors reviewed records | ❌ Not checked | ❌ Not checked |
| FAI / PPAP documentation supported | ✅ CMM-enabled full PPAP | ⚠️ Varies by factory | ⚠️ Varies |
| FTA / CO documentation managed | ✅ Every shipment, all FTA markets | ⚠️ Factory-dependent | ⚠️ Agent-dependent |
| English project management | ✅ Dewin manages all comms | ⚠️ Variable | ⚠️ Variable |
How Dewin Manages Your Program
Part Review & DFM
Dewin reviews your drawing for die casting DFM suitability — wall thickness, draft angles, parting line, post-machining features. We flag issues before tooling is cut.
Factory Qualification
Tho Thanh Phat has completed Dewin's 50-point Dolphin Audit. We confirm process capability for your specific part — die casting machine size, CNC milling/lathe specs, CMM measurement range.
Tooling & First Article
Dewin oversees tooling development. First article inspection uses the factory's 3D CMM — full dimensional report delivered to you before production approval.
Production Oversight
On-ground milestone checks during production runs. In-process CMM sampling to catch dimensional drift from die wear early in the production run.
Pre-Shipment Inspection
Dewin conducts AQL Level II pre-shipment inspection before container loading — including CMM spot-checks on critical dimensions and Certificate of Origin verification.
Full Docs + Delivery
Complete documentation package: Certificate of Origin (applicable FTA form), material certs, CMM inspection report, PSI report, commercial invoice, packing list.
What Buyers Say About Dewin's Vietnam Factories
"We needed FAI dimensional reports and PPAP-compatible data from our Vietnam die casting supplier. Dewin found a factory with in-house CMM — it changed what we could source from Vietnam entirely."
Francisco García Quintana
LAROME
"The quality documentation from Dewin's Vietnam factories — FAI reports, material certs, real CMM data — matches what we expect from domestic suppliers. That's rare at Vietnam price points."
Greg L. Wilhite
DOMS Precision
"What convinced us was the factory photos and the audit report. Real machines, real photos, real CMM data. Not a sales deck."
Vishnu Shanker
Texas Technology
Source Precision Die Cast Parts from Vietnam's Audited Factory Network
Get matched to Tho Thanh Phat or another Dewin-audited die casting factory. Real factory photos, Dolphin audit results, and complete FTA + COO documentation managed end-to-end.