Why Switching Fails

Changing a zipper supplier looks like a purchasing decision and behaves like an engineering project. The new factory can make a zip that meets the drawing and still fail the garment, because the drawing never captured the tape hand, the slider feel, the way the tape behaves after three washes, or the fact that the old supplier quietly adjusted the chain width two years ago to fix a puckering problem.

Most failed switches are not failures of capability. They are failures of transfer. The knowledge that made the old supply work lives in samples, emails and one engineer's memory, and none of it moves unless the handover is planned as a sequence with dates, owners and exit criteria.

The 90-Day Handover Plan

  1. Days 1 to 10: freeze the reference. Collect the current specification, the last three approved samples, the last twelve months of inspection data and every deviation granted. Nothing can be transferred that has not been written down.
  2. Days 11 to 25: re-specify. Rewrite the specification as a test plan with methods and sample sizes, not as a copy of the old catalogue entry. Resolve every undocumented adjustment with the outgoing supplier before it closes the account.
  3. Days 26 to 45: sample and approve. New supplier submits proto, size set and pre-production samples against the new specification; approvals follow the sampling sheet, with measured results rather than photographs.
  4. Days 46 to 70: parallel run. Both suppliers produce the same article. Run the same inspection plan on both lots and compare defect rates by class, not in aggregate.
  5. Days 71 to 85: pilot shipment. Ship a small order through the real logistics route, including labelling, marks and customs documents.
  6. Days 86 to 90: cut-over review. Compare pilot results to the acceptance criteria, confirm capacity, and set the date after which the old supplier is no longer authorised to ship.

Handover Checklist

[ ] Current specification with revision number and date
[ ] Last 3 approved samples, signed, sealed, labelled
[ ] Approved colour standards, physical, stored dark
[ ] Last 12 months of inspection reports by lot
[ ] All deviations and concessions, with expiry dates
[ ] Tooling list: moulds, dies, sliders, owned by whom
[ ] Tooling condition report and transfer or disposal date
[ ] Open orders, balances and cancellation terms
[ ] Outstanding claims, credits and chargebacks
[ ] Test reports: tensile, cycle, fastness, nickel, pH
[ ] Compliance certificates and expiry dates
[ ] Packaging drawings, carton specs and mark artwork
[ ] Barcode and label files, print-ready
[ ] Capacity commitment from the new supplier, per month
[ ] Sub-supplier list: tape mill, slider moulder, dyer
[ ] Contact matrix and escalation path, both sides
[ ] Cut-over date, last ship date, buffer stock quantity
[ ] Ownership of the buffer stock and who pays for it

Parallel Run and Cut-Over Rules

The parallel run is the only stage that produces comparable data, and it is the stage most often skipped to save six weeks. Run both suppliers against the same inspection plan, on the same article, in the same season. Compare major defect rates, cycle-test results and colour difference against the same standard. A new supplier that is 20 percent worse on majors before the volume ramps will be 40 percent worse after it.

  • No cut-over until the new supplier passes two consecutive lots under the full AQL plan.
  • Keep a buffer of 4 to 6 weeks of consumption, owned and paid for by the buyer, not held informally at the factory.
  • Define the last ship date for the old supplier in writing, with a final inspection before it.
  • Do not run both suppliers on the same dye lot reference; colour will drift and the comparison becomes invalid.

Tooling, Samples and the Question of Ownership

Ask who owns the slider mould before you need to ask for it back. Tooling paid for by the buyer should be listed by asset number, photographed, and covered by a bailment clause that gives the buyer the right to remove it on notice. Tooling that is merely "used for your orders" belongs to the factory, and will not travel.

Sample custody matters just as much. The outgoing supplier should return or destroy buyer-owned samples and colour standards at the end of the transition, and confirm in writing that it has done so. A standard that stays in a closed factory is a standard nobody can measure against.

The Quiet Risks

Three risks hide in a switch. The first is a sub-supplier change: the new factory buys tape from a different mill, and the hand of the finished zip changes without any specification being violated. The second is a seasonal capacity promise made in the low season and withdrawn in the high season. The third is institutional memory, which leaves with the merchandiser who handled your account for nine years.

Donglong handles transitions by assigning one engineer to the incoming supplier for the full 90 days, with authority to stop the cut-over. A named owner with a stop authority is worth more than a longer checklist, because a checklist without a decision-maker becomes a document that everyone signs and nobody reads.

A Note on Use

This checklist is general commercial reference, not legal advice. Tooling ownership, termination notice and liability during transition depend on the existing supply agreement and local law. Have qualified counsel review the handover terms before the cut-over date is fixed.