"Exiting a Chinese Supplier: Handover Without Downtime"
Short answer: Plan the exit as a 12-16 week dual-running programme, not a switchover. Order a buffer of 4-8 weeks of finished parts before you give notice, secure written confirmation of tooling ownership, and requalify the new source with a first-article inspection plus a 3-batch capability run before you release the last purchase order to the old supplier. Expect 2-4 weeks for tooling transfer, 3-5 weeks for sampling and approval, and 4-6 weeks of overlapping production. The single biggest cause of downtime is not the new supplier's quality — it is discovering at week 10 that the old supplier will not release tooling, gauges, or the final revision of the drawing.
Why supplier exits go wrong more often than they should
Most buyers treat a supplier exit as a purchasing decision. It is actually a logistics and documentation project with a commercial negotiation bolted on. The parts you buy are the output of a chain: drawings, tooling, fixtures, gauges, process parameters, sub-supplier approvals, packaging specs, and accumulated tribal knowledge about which dimensions drift.
When you move that chain to a new factory, every link has to be reconstructed or transferred. Buyers who plan only the "new supplier" half of the project routinely hit three failures: tooling held hostage, a drawing revision mismatch that produces a part that fits nothing, and a quality wall that appears at batch three rather than batch one.
The three failure modes
Tooling and gauge retention. If the tooling was amortised in the piece price rather than invoiced separately, ownership can be genuinely ambiguous in practice even when the contract says otherwise. See our notes on tooling ownership terms before you open the conversation.
Revision drift. The old supplier may be running Rev D while your file says Rev C, with a deviation approved by email two years ago that nobody remembers. The new supplier builds to Rev C and the part does not assemble.
Ramp-up quality wall. Samples pass, the first production batch passes, and then batch three shows a capability problem on one tight dimension because the new supplier's process window is narrower than the old one's.
What does a realistic exit timeline look like?
The table below is a typical, indicative schedule for a precision metal part with existing tooling. Compress it only if you are willing to carry more buffer stock.
| Phase | Weeks | Key activities | Owner |
|---|---|---|---|
| Preparation | 1-2 | Drawings frozen, revision audit, buffer stock ordered, tooling list built | Buyer |
| Negotiated handover | 3-5 | Tooling release agreed, gauges packed, process records requested | Buyer + old supplier |
| New source selection | 3-6 | RFQ issued, capability review, NDA and quality agreement signed | Buyer |
| Tooling transfer and sampling | 6-10 | Tooling shipped, first-article inspection, dimensional report | New supplier |
| Capability run | 10-13 | 3 production batches, Cpk on critical dimensions, packaging trial | New supplier |
| Dual running | 12-16 | Both sources live, old supplier volume tapered, final acceptance | Buyer |
| Close-out | 16-18 | Last PO closed, tooling registered as your asset, lessons logged | Buyer |
Note the overlap. Dual running from week 12 to week 16 is not waste — it is the insurance policy that lets you taper the old supplier instead of cutting over on a date.
How do you protect tooling, gauges, and drawings before you talk?
Do the paperwork audit before you signal intent. The moment a supplier believes volume is leaving, cooperation becomes a commercial negotiation, and you want your evidence assembled first.
The pre-exit document pack
Build a single folder containing: the current drawing revision with a change history, the tooling list with asset numbers and photographs, gauge and fixture lists with calibration certificates, the last 12 months of inspection reports, packaging drawings, material certificates, and any approved deviation notes.
Cross-check the drawing revision against the last shipment's inspection report. If the report references a dimension that does not exist on your drawing, you have revision drift and you need to resolve it before transfer, not after.
Confirm ownership in writing
Ask for a short written confirmation that tooling, fixtures, and gauges identified in the list are the buyer's property and will be released on request. If the contract is silent or the tooling was amortised, be prepared to negotiate a release payment. Budget for it rather than being surprised by it.
How do you select and qualify the new source without gambling?
Qualify on process, not on price alone. A supplier who is 8% cheaper but has never held your tightest tolerance is not cheaper once you count the downtime.
What to send in the RFQ
Send the drawing, the annual volume with a monthly breakdown, the material specification, the surface finish and plating requirements, the packaging spec, and — critically — a sample of a known-good part. A physical golden sample removes more ambiguity than three pages of notes.
Ask each candidate to return a process plan: how they will make the part, which operations are in-house, which are subcontracted, what the critical dimensions are, and how they will measure them.
First article and capability run
Require a full first-article inspection report against every dimension on the drawing, not just the critical ones. Then require three consecutive production batches with capability data on the dimensions that matter. For a stamping or spring, add a functional test — load, deflection, fatigue, or fit — because dimensional conformance alone does not prove the part works.
A supplier running CNC machining at ±0.005 mm and stamping under one roof can usually absorb a transfer like this without splitting the project across two vendors, which reduces the number of handover points you have to manage.
| Qualification gate | Evidence required | Pass criterion |
|---|---|---|
| Document review | Process plan, control plan, material certs | All operations identified, no unexplained subcontracting |
| First article | Full dimensional report + material cert | 100% of drawing dimensions within tolerance |
| Capability run | 3 batches, 30+ pieces per critical dimension | Cpk ≥ 1.33 on critical dimensions |
| Functional test | Load, fit, or fatigue result | Meets drawing functional requirement |
| Packaging trial | Drop and transit test | No damage, matches spec |
How much buffer stock do you actually need?
Buffer stock is the cheapest insurance in a supplier transition. Size it from the real numbers, not a rule of thumb.
Take your weekly consumption, multiply by the expected transition duration, and add a safety margin for the failure of one qualification gate. If you consume 5,000 pieces a week and the transition is 12 weeks with one likely rework loop of 2 weeks, you need 70,000 pieces — or a plan to dual-source part of the volume earlier.
| Weekly usage | Transition length | One-gate slip | Recommended buffer |
|---|---|---|---|
| 1,000 | 12 weeks | 2 weeks | 14,000 |
| 5,000 | 12 weeks | 2 weeks | 70,000 |
| 20,000 | 12 weeks | 2 weeks | 280,000 |
| 1,000 | 16 weeks | 3 weeks | 19,000 |
For high-volume stampings and springs, buffer stock is bulky and expensive to store. In those cases, run the old supplier at reduced volume for longer rather than building a warehouse. A tapering schedule — 100%, 70%, 40%, 0% over six weeks — usually costs less than the working capital tied up in finished goods.
How do you manage the conversation with the outgoing supplier?
Keep it professional and specific. Most suppliers respond badly to vague news and reasonably to a clear plan.
Sequence the message
Tell them the volume is moving, give a taper schedule with dates, confirm what you need from them (tooling, gauges, records, last-time-buy pricing), and put it in writing. Do not announce the exit before you have buffer stock on the floor.
Handle the last-time buy
Ask for a last-time-buy quotation on finished parts and on any long-lead sub-components. This is often the fastest way to extend your buffer without new tooling.
If cooperation stalls
Escalate in writing, reference the contract clause on tooling ownership, and set a deadline. If the value justifies it, a formal letter from your legal counsel usually resolves the issue faster than repeated emails. Our escalation process guide covers the sequence that works without burning the relationship.
What should the new supplier's quality agreement cover?
A quality agreement turns verbal expectations into auditable commitments. It should define the drawing revision that governs, the inspection frequency and sampling plan, the measurement method and gauge for each critical dimension, the change-notification window, the non-conformance process, and the traceability requirements.
Be explicit about change control. A supplier who changes a sub-supplier, a tool, or a process parameter without telling you can invalidate months of qualification work. A 30-day written notification requirement for any process change is standard and reasonable.
Pair this with a clear quality agreement that names the responsible quality contact on both sides, so problems reach a decision-maker rather than a shared inbox.
How do you close out the exit cleanly?
Close-out is where most buyers lose the value of the work. Register the tooling as your asset with photographs and asset numbers. Archive the final inspection reports and the approved drawing revision. Record the actual transition duration and the gates that slipped, so the next transfer is faster.
Then review the new source at 30, 60, and 90 days. Watch the defect rate, the on-time delivery rate, and the response time on engineering questions. A transition is only complete when the new supplier is boring.
If you are planning an exit and want a second source quoted in parallel, BQUQ runs CNC machining, metal stamping, custom springs, and heat sink production across four lines in one Dongguan factory, quotes in 12 working hours, and accepts flexible MOQ for transfer projects. Send drawings to sc@bquq.com.
Frequently Asked Questions
Q: How long does it take to move a part from one Chinese supplier to another?
A: For a part with existing tooling, plan 12-16 weeks including dual running. Tooling transfer and shipping typically takes 2-4 weeks, first-article inspection and approval 3-5 weeks, and the capability run across three production batches another 3 weeks. Add 2 weeks if a qualification gate slips. Parts requiring new tooling add 3-6 weeks for tool manufacture and trial.
Q: Who owns the tooling if it was amortised into the piece price?
A: Ownership depends on the contract wording, and amortised tooling is the most common source of dispute. If the contract does not clearly state that tooling is buyer property, expect to negotiate a release payment. Before starting any exit, request written confirmation of ownership and a tooling list with asset numbers, photographs, and current condition notes.
Q: Can I avoid downtime without building a large buffer stock?
A: Yes, by tapering rather than switching. Run the old supplier at 100%, then 70%, then 40%, then zero over roughly six weeks while the new supplier ramps. This spreads risk without tying up working capital in finished goods. It works best when the old supplier remains cooperative, so keep the relationship professional and give clear dated schedules.
Q: What documents should I collect from the outgoing supplier?
A: Collect the current drawing revision with change history, the tooling and gauge list with calibration certificates, the last 12 months of inspection reports, material certificates, packaging drawings, approved deviation notes, and process parameter records. Cross-check the inspection reports against your drawing before transfer — revision drift is common and is far cheaper to fix before the tooling moves.
Q: What happens if the new supplier fails the capability run?
A: Treat it as a normal gate, not a crisis. Ask for a root-cause analysis and a corrective action plan, then re-run the three-batch capability study after the fix. Keep the old supplier live and the buffer intact while this happens. If the second run also fails, the process plan is usually wrong rather than the supplier's execution.
Related Resources
- About BQUQ and our four production lines in Dongguan: /about/
- CNC machining, metal stamping, springs, and heat sinks: /cnc-machining/, /custom-metal-stamping/, /compression-springs/
- Industry trends affecting sourcing decisions: /industry-dynamics/
- Technical articles on tolerances, inspection, and tooling: /bquq-blog/
- Common sourcing and quality questions: /faq/
- Transfer and qualification case studies: /case/
- Talk to an engineer about a parallel quote: /contact/
Authored by the BQUQ Engineering Team. BQUQ (Dongguan) runs CNC machining (±0.005 mm), metal stamping, custom springs, and heat sink production in one ISO9001 factory. Source-direct from Dongguan, China — quote in 12 hours: sc@bquq.com | WhatsApp +86 13713157787 | www.bquq.com
