Last updated: 2026-09-02 · 5 min read

How Do You Evaluate an Injection Mold Supplier in China — What Evidence Matters More Than Claims?

Evaluating a Chinese mold supplier requires five evidence-based checks: reviewing T1 samples and CMM reports from past molds (not brochure claims), verifying the equipment list against the part requirements (CNC, EDM, CMM — not machine count), checking the engineer-to-worker ratio (design capability, not headcount), requesting customer references with contactable names (not anonymous testimonials), and confirming export packaging and logistics experience (not just FOB capability). The suppliers who pass all five checks are the credible alternatives to local toolrooms — the rest are quoting on price alone.

Runner system — The channel network that delivers melt from the machine nozzle to each cavity. Cold runner: solidifies between shots, produces runner waste. Hot runner: stays molten, eliminates runner waste but adds $15k–$40k to mold cost. See also related guide.

Key Facts

  • The most reliable evidence of capability is a T1 sample with a matching CMM report — the report shows the supplier can hold tolerances on a real part, not just claim they can on a brochure.
  • Equipment matters less than utilization: a shop with 3 CNC machines running 24/7 produces more than a shop with 10 CNC machines running one shift. Ask for machine utilization rates, not just the machine list.
  • Export experience is verified by asking for photos of past export packaging (crate construction, rust protection, shock indicators) and the names of freight forwarders they have worked with — not by asking “do you export?”

    • Runner system — The channel network that delivers melt from the machine nozzle to each cavity. Cold runner: solidifies between shots, produces runner waste. Hot runner: stays molten, eliminates runner waste but adds $15k–$40k to mold cost. The related guide covers adjacent topics.

    Supplier Evaluation Checklist

    Check What to Request Red Flag
    T1 sample quality 3–5 samples from recent molds with matching CMM reports No samples available or samples without reports
    Equipment capability Machine list with brand, model, age and utilization rate Only machine count provided; no brand or age data
    Engineering capability Engineer-to-worker ratio; DFM report samples No engineers on staff; all design outsourced
    Customer references 2–3 contactable references with company names Anonymous testimonials or “confidential” for all references
    Export experience Photos of export packaging; freight forwarder names No export photos; has never shipped by sea freight

    What to Look for in a Factory Visit

  • Shop floor organization: a clean, organized shop floor with labeled tooling, documented processes and visible quality stations indicates a shop that manages its work — not necessarily the biggest shop, but one that delivers consistently.
  • In-process inspection: watch for operators using calipers, micrometers or CMM during production — not just at the end. In-process inspection catches problems before they become scrap; end-of-line inspection only sorts good from bad.
  • Mold storage and preservation: molds stored on racks with rust protection, labeled with mold number and last production date indicate a shop that maintains its tooling — a sign of long-term thinking, not just order fulfillment.

    • What This Means for Your Quotation

    The quotation request should include your evaluation criteria — T1 sample quality, equipment capability, engineering capability and export experience — so the supplier responds with evidence, not just a price. The supplier who provides T1 samples, CMM reports and references with the quotation demonstrates capability; the supplier who provides only a price demonstrates nothing beyond their willingness to quote.

    Frequently Asked Questions

    How do you verify a supplier’s claims about mold life and shot count?

    Request the mold maintenance log for a mold that has reached its guaranteed shot count — the log shows actual production counts, maintenance dates and any repairs. A supplier who maintains logs can verify mold life claims with data; a supplier who cannot maintain logs is unlikely to maintain molds to the claimed standard.

    Is it safe to send drawings to a Chinese mold supplier?

    IP protection is a risk management issue, not a yes-or-no question. The mitigation is structural: NDA before disclosure, patent registration in China before sharing critical features, and supplier segmentation so no single supplier holds the complete design. The risk exists in any country — the mitigation is the same regardless of geography.

    What is the typical payment structure for mold orders?

    The standard structure is 30–50% deposit, 40–50% at T1 sample approval, 10–20% before shipment. The key is tying each payment to verifiable evidence — not calendar dates. The deposit triggers steel purchase (verify with steel purchase receipt); the T1 payment triggers on approved samples with CMM report; the final payment triggers on pre-shipment inspection.

    Key Takeaways

    1. Evaluate suppliers with evidence — T1 samples with CMM reports, equipment utilization data, contactable references and export packaging photos — not brochure claims, machine counts or anonymous testimonials.
    2. The factory visit reveals shop floor organization, in-process inspection practices and mold storage conditions — indicators of consistent delivery, not just capability.
    3. The quotation request should include your evaluation criteria so the supplier responds with evidence — the supplier who provides proof with the quotation demonstrates capability beyond price.

    Send aCatMould your evaluation criteria with the RFQ, and the response includes T1 samples, CMM reports, equipment data and contactable references — so the supplier evaluation is based on verifiable evidence, not claims.

    Sources
    MoldMaking Technology — supplier qualification and audit
    Plastics Technology — sourcing molds from China
    SPE — supplier evaluation and qualification guidelines

    Sources: Plastics Technology · Plastics Technology Online · Society of Plastics Engineers (SPE) · ThomasNet