Buyers should measure on-time delivery against one mutually controlled promise date per order line or approved tooling milestone, then count an item as on time only when the required quantity and agreed acceptance evidence are available. Separate injection mold lead time from repeat production delivery, keep buyer-approved date changes visible, and review delivery together with the injection molding quality report. This prevents a supplier from appearing punctual when parts are incomplete, awaiting disposition, or delivered against a date that was quietly moved.
Use two delivery views: committed-date performance shows whether the supplier keeps its promise; revised-date performance shows the current recovery position. Do not blend them into one score.
01
H2: Define the delivery event before calculating a percentage
On-time delivery is a contract and data-definition question: what was promised, in which quantity, at which handover point, and with what evidence? Define a delivery event for every purchase-order line and production tooling milestone. Identify the promise date, required quantity, handover point, acceptance gate, and record that proves completion.
For molded parts, use accepted, complete quantity available at the named handover point by the confirmed date. A carton that arrives on time but has a shortage, a blocked inspection result, or missing required documents should not be scored as fully successful. Keep receipt and acceptance timestamps separate so logistics delay and quality disposition are not confused.
For tooling, do not call a mold delivered simply because it left the tool shop. Production tooling may have commitments for design release, tool assembly, trial samples, measurement review, buyer approval, shipment, and production readiness. Choose the milestone that supports the launch decision and apply it consistently. Injection molding lead time includes design, material availability, tooling manufacture, quality control, and delivery (Reference 3).
02
H3: Lock the promise date and preserve its history
Set the baseline after the supplier acknowledges the purchase order or tooling plan in writing. It may be the buyer’s requested date or a supplier countercommitment that the buyer accepts. Record date, time zone, quantity, delivery point, and confirmation source. A forecast is not an OTD commitment until both parties agree how it will be treated.
Changes are normal in injection molding. A CAD revision can reopen DFM, a resin approval can move material release, and a customer request can change inspection scope. Keep the original confirmed date. Add a revised date only with a change reference, approval date, cause code, and owner. Report original-commit OTD and latest-approved-plan OTD side by side to distinguish execution from buyer-driven scope change.
03
H2: Use an accepted, complete delivery formula
At order-line level, calculate Accepted OTD as: eligible lines delivered on or before the controlled promise date, in the required quantity and acceptance state, divided by all eligible lines due in the reporting period, multiplied by 100. Exclude only lines identified by a written rule before reporting, such as cancelled lines or approved buyer holds. Do not exclude a late line merely because it was later re-planned.
Measure scheduled releases by line, not only by the whole purchase order. Define how partial deliveries count before reporting; a buyer may require the complete quantity on time, or score planned partial releases line by line. A quantity-weighted companion measure can show exposure, but should not replace line-level OTD because a large order can hide repeated misses on smaller critical releases.
Avoid measuring only dispatch. It is useful for transport management, but does not show whether the buyer received usable parts. Track dispatch, carrier handover, arrival, receipt, and acceptance separately. Customs, port congestion, and buyer-nominated freight need visible cause codes rather than silent attribution to molding performance.
04
H2: Compare suppliers with the same scorecard and evidence
Compare suppliers only when scope, date rule, receiving point, and reporting window are the same. NIST recommends a balanced, vendor-tailored scorecard with measures such as responsiveness and on-time delivery, while noting that KPIs are lagging indicators. ASQ similarly treats quality, cost, and delivery as core supplier-performance indicators (References 1 and 2). Delivery should sit beside quality, communication, and change-control evidence rather than decide selection alone.
Use a rolling view plus an exception log. The rolling view reveals execution patterns. The log identifies whether a miss arose in tool design, purchased components, machine availability, resin release, inspection, packaging, freight, or a buyer-driven change. A good average can still create launch risk if misses cluster around first trials, changes, or constrained resins.
| Supplier comparison measure | Supplier A | Supplier B | Evidence to review |
|---|---|---|---|
| Original-commit accepted OTD | Rolling result using identical eligible-line rule | Rolling result using identical eligible-line rule | PO acknowledgement, original date, receipt and acceptance timestamps |
| Latest-approved-plan OTD | Rolling result shown separately | Rolling result shown separately | Approved change log with cause and date |
| Complete-quantity performance | Compare scheduled versus accepted quantity by release | Compare scheduled versus accepted quantity by release | Packing list, goods receipt, shortage record |
| Tooling-milestone reliability | Compare each agreed trial or approval milestone | Compare each agreed trial or approval milestone | Milestone plan, trial report, approval record |
| Quality-at-delivery status | Review released, held, reworked, or rejected lots | Review released, held, reworked, or rejected lots | Injection molding quality report and nonconformance record |
| Recovery responsiveness | Compare notice timing and corrective-action follow-through | Compare notice timing and corrective-action follow-through | Dated status updates, containment and corrective-action records |
05
H3: Connect delivery to quality release, not just shipping activity
A timely shipment can still be a late operational delivery if it cannot be released for use. Define the required injection molding quality report in the PO, quality agreement, or control plan. It may include part number and revision, lot and resin traceability, cavity or mold identification where relevant, sample size, dimensional and visual results, test results, disposition, and any deviation reference.
Keep quality and delivery measures distinct but connected. If a lot arrives by the promised date yet is rejected, report the shipping result and accepted-delivery result separately. Link any replacement or rework to the original due line so the operational impact remains visible.
06
H2: Run a practical review cadence for tooling and production
During injection mold lead time, request a milestone plan that shows dependencies rather than a single finish date. Useful checkpoints include DFM closure, tool-design release, long-lead component status, machining and assembly, trial, sample measurement, corrective actions, buyer review, and shipment or production release. The buyer needs enough dated evidence to see what could move the critical path.
After launch, review near-term overdue or at-risk releases first, then the rolling scorecard and recurring cause codes. Assign actions with owners and dates. For cross-border programs, agree ownership for export documents, freight booking, customs inputs, and delay notification. A timely warning is valuable, but is not on-time delivery; retain both measures.
In an injection molding RFQ, ask each bidder how it confirms dates, records revisions, reports capacity constraints, handles partial releases, and provides trial and quality evidence. Use the same response format for all bidders. Request a quote with CAD, drawing, forecast, delivery point, quality requirements, production tooling scope, and a proposed milestone or release schedule so InjeForm can return a traceable planning basis.
Practical takeaway
Before you move
to the next review.
- Define whether the score is based on dispatch, receipt, or accepted usable quantity, and use one definition per program.
- Record the original supplier-confirmed promise date, quantity, handover point, and time zone for every eligible line or tooling milestone.
- Keep original-commit OTD and latest-approved-plan OTD as separate measures.
- Decide in advance how partial deliveries, early deliveries, cancelled lines, buyer holds, and approved concessions are counted.
- Link each delivery record to the required injection molding quality report and final lot disposition.
- Use the same reporting period, data fields, and cause-code taxonomy when comparing suppliers.
- Review tooling milestones separately from repeat-production releases so a trial delay is not hidden in shipment data.
- Require an exception log with notification date, root cause, containment, recovery action, owner, and next confirmed date.
FAQ
Common questions
What is the best OTD formula for an injection molding supplier?
Use accepted, complete order lines delivered on or before the controlled promise date divided by all eligible order lines due in the period. Keep shipment and receipt timestamps as supporting measures, but do not treat a line as fully successful if the required quantity or acceptance evidence is missing.
Should a supplier be penalized when the buyer changes the part design?
Do not erase the original commitment. Log the approved design change, its date, scope, and owner, then display original-commit OTD beside latest-approved-plan OTD. This preserves the program impact while separating buyer-driven change from supplier execution.
How should tooling delivery be measured?
Measure the buyer-relevant production tooling milestone, such as approved T1 evidence, accepted trial samples, tool shipment, or production readiness. Define the milestone and its acceptance evidence before tool build starts; do not rely only on a stated mold-completion date.
Does an on-time shipment count if the lot fails inspection?
It can count as on-time dispatch or arrival, but it should not count as accepted delivery if the agreed release requirement is not met. Report the logistics event and the quality disposition separately, then link any replacement or rework to the original line.
What should buyers request as delivery evidence during a mold build?
Request a controlled milestone plan, dated status updates for critical dependencies, tool trial reports, sample measurement results, corrective-action status, and the agreed approval or shipment record. The exact evidence should match the part risk, production tooling scope, and buyer acceptance process.
References
Source material
- [1] National Institute of Standards and Technology, How Small Manufacturers Can Develop Risk Management Strategies for Their Supply Chains
- [2] ASQ, Supplier Quality Management
- [3] Midstate Mold & Engineering, How to Calculate Your Plastic Injection Molding Project Lead Time
This guide is general information for early procurement and engineering discussion. It does not replace product-specific DFM, qualification, validation, regulatory assessment or legal advice.