CNC Machining & Injection Molding — DFM/Moldflow Support, CMM Inspection, Prototype to Production Solutions.
A mold trial is the release gate used to decide what can be approved, what must remain steel-safe, and what evidence is required before the next sampling stage. This working matrix defines whether dimensions, cosmetic surfaces, cavity balance, assembly fit, and process repeatability are ready for approval or still require correction based on CTQ review scope, stable-shot conditions, cavity-specific traceability, and molding condition sheets.
Upload CAD and CTQ List for Trial-Readiness ReviewFocuses on mold open-close function, ejection movement, cooling circuit integrity, and initial fill behavior. T0 confirms basic tool integrity but should not be used for dimensional approval, cosmetic release, or assembly validation.
The first engineering review to map visual defects (sink, flash, weld lines) and establish an initial CTQ dimensional baseline against the released drawing revision. Key outputs: defect maps and cavity-tagged samples.
Verifies that T1 steel-safe adjustments were effective. Reviews repeatability across stable shots, cavities, and key CTQ features through meticulous cavity-to-cavity comparison and data review.
Final validation for long-run stability, Cpk evidence, and PPAP documentation. This stage provides the capability studies required to support final production release readiness.
These are common false-approval risks that distort mold trial decisions and delay final sign-off.
| Stage | Main Objective | What Can Be Approved | What Cannot Be Concluded | Minimum Evidence Required | Next Engineering Action |
|---|---|---|---|---|---|
| T0 | Tool Function & Fill Feasibility | YES Mold open-close function, ejection movement, cooling flow continuity, and basic fill behavior. | NO Measured dimensions, cosmetic finish, or optimized cycle time. | Ejection video, short-shot filling sequence (~95% fill), and basic venting/burn-mark observations. | Prepare for T1 steel-safe tuning baseline. |
| T1 | Dimensional Baseline & Defect Map | YES Initial weld line positions, sink marks, and cosmetic visual baseline. | NO Cpk/Capability studies, final texture/graining, or assembly-ready certification. | Ballooned FAI or CTQ dimensional report against the released drawing revision, plus cavity-identified defect mapping. | Steel-safe or metal-off corrections for T2. |
| T2 | Verification of Corrections | YES Correction effectiveness, assembly fit, gate balance, and cavity-to-cavity consistency. | NO Final PPAP sign-off or high-volume long-run stability. | CTQ re-measurement and cavity-identified samples retained from a defined stable-shot window. | Texture release or Pilot/T3 validation run. |
| Pilot / T3 | Capability & Production Readiness | YES Production process window, capability stability, and reviewed cycle time under controlled run conditions. | NO Further tool steel changes (Process must be frozen). | Cpk or capability evidence, plus continuous 4–8 hour pilot-run records with process stability data. | Final production release and mold sign-off. |
No. T0 samples are unsuitable for engineering sign-off on dimensions. At this early stage, measured dimensions may shift once resin drying, thermal equilibrium of the mold, and a controlled process window are established. T0 is strictly for tool-function and fill-behavior review, occurring before a controlled condition sheet and stable-shot definition are established.
Approving dimensions at T0 creates a high risk of "false positives," where parts appear within tolerance but drift out during a stable production run. For deeper validation of critical tolerances and long-term stability, refer to our guide on process window validation for CTQ stability and capability review and our standard mold approval criteria before sign-off.
To ensure a mold trial produces actionable engineering data rather than uncontrolled or non-comparable samples, the following inputs must be frozen and verified before the press run begins.
Confirmation of the released drawing revision and any pending Engineering Change Orders (ECO). Trial results are only valid when measured against a released drawing revision and defined change status.
Uncontrolled resin grade, drying conditions, or lot consistency are common causes of T1 dimensional drift and cosmetic variation. All material must have verified drying logs and lot traceability.
resin selection and drying risk for mold trialsPre-select machine tonnage, tie-bar spacing, shot size, platen fit, and nozzle interface. Mold status, including cooling flow and ejection stroke, must be verified before the trial run begins.
Define CTQ features on a ballooned drawing and lock the cavity ID logic. This ensures inspection focus is aligned with downstream fit, sealing, functional, and appearance risks.
which molded tolerances should be reviewed as CTQ at T1Freeze the trial objective and acceptance evidence in advance, including whether the run is for fill balance review, dimensional sign-off, correction verification, or texture release.
Define who approves steel-safe changes, who closes corrective actions, and who signs part acceptance at each trial stage to ensure engineering closure and accountability.
| Program Type | Extra Freeze Requirements | Engineering Purpose |
|---|---|---|
| Automotive | PPAP level definition, full cavity traceability, control-plan-linked CTQ | Risk mitigation and mass production stability validation |
| Medical | IQ/OQ/PQ trigger points, resin lot traceability, cleanliness or cleanroom requirements if applicable | Regulatory validation readiness, traceability control, and cleanliness risk control |
| Aerospace | AS9102 FAI scope, revision lock, material certification path | Flight-critical safety, configuration control, and traceability |
| General Industrial | FAI scope, condition sheet baseline, steel-safe action logic | Standard quality assurance, corrective-action closure, and clearer next-trial decisions |
A standardized request package locks the drawing revision, resin specification, inspection scope, and required outputs before the trial run starts, reducing repeat trials caused by incorrect revisions, resin grades, or missing inspection instructions.
| Field Category | Required Data Points | Engineering Value (The "Why") |
|---|---|---|
| Project & Design Info | Project ID, Mold #, Part #, released drawing revision, and ECO status (open/closed) | Prevents sampling against outdated CAD or unverified Engineering Change Order status. |
| Trial Stage & Purpose | Stage (T0/T1/T2/Pilot), Engineering Objective | Defines the acceptance logic: T0 for tool function/fill behavior, T1 for CTQ/defect baseline, T2 for correction verification. |
| Machine & Resin Spec | Tonnage, shot size, nozzle type, exact resin grade, lot number, and drying time/temp | Ensures resin behavior, moisture control, and lot consistency are aligned with the intended production specification. |
| Inspection Request | CTQ list, cavity ID logic, ballooned drawing reference, and FAI scope | Directs the quality team on which CTQ features and cavity-tagged samples must be reviewed at the press versus in the lab. |
| Required Outputs | Condition sheet, cavity-identified samples/photos, defect map, and ballooned FAI or CTQ report | Standardizes the evidence package required for steel-safe correction decisions. Review typical FAI PPAP and quality documents. |
| Internal Sign-off | Project Manager, Tooling Engineer, and QC Lead sign-off | Ensures all technical functions have verified tool, material, and inspection readiness before the trial run begins. |
A trial execution plan controls the setup sequence, sampling rules, recording method, and release gates required for repeatable engineering data. This plan goes beyond scheduling by defining the controlled sequence used to confirm fill behavior, stable-shot conditions, cavity traceability, and next-trial decisions. For deep validation logic, review our process window validation for CTQ stability and capability review.
| Step / Sequence | Critical Engineering Action | Responsible Role | Evidence Captured | Release Gate |
|---|---|---|---|---|
| Step 01 Machine Setup | Establish the molding baseline by confirming barrel zones, mold temperature, nozzle type, machine ID, and initial process-window targets. | Process Engineer | Condition sheet baseline with barrel zones, mold temperature, nozzle type, and machine setup record. | Thermal Equilibrium |
| Step 02 Filling Analysis | Run the short-shot sequence to evaluate cavity fill behavior, filling balance, and venting response, then identify gate-freeze timing and the initial V/P switchover point. | Tooling Engineer | Short-shot sequence record, filling-balance observations, and initial gate-freeze notes. | 95% Fill Pattern |
| Step 03 Process Stability | Define the hold-pressure profile and cooling flow, then verify part-weight consistency and visual stability across consecutive cycles. | Process Engineer | Weight Stability Log and process window boundaries. | Stable Weight Trend |
| Step 04 Data Sampling |
Apply cavity-specific stable-shot rules and retain samples only after thermal stabilization and a defined stable-shot window are confirmed.
trial condition sheet and stable-shot record template |
QC Inspector / QE | Cavity-identified stable-shot samples linked to the condition sheet and sampling window. | Traceability Verified |
| Step 05 Closing Review |
Close the trial review by checking defect mapping, assigning steel-safe or metal-off actions, and confirming ownership for the next trial stage.
issue tracking sheet for T1 corrective actions and steel-safe follow-up |
Project Manager | Trial issue list, defect map, corrective-action owner, and next-trial decision record. | Tuning Approved |
| Inspection Item | Method / Engineering Basis | Required Typical Output |
|---|---|---|
|
Visual Defects Flash, sink, weld line, burn, jetting |
Visual (D65)
Comparison Samples → root cause guide for mold-trial defects |
Cavity-specific defect map with annotated photo evidence |
|
CTQ Dimensions Functional & steel-safe zones |
CMM / OMM / Caliper Measured against the released ballooned drawing revision. → tolerance standards for CTQ review |
Ballooned FAI or CTQ dimensional report |
|
Weight & Stability Repeatability & cavity balance |
Digital Scale (0.001g) Data collected by cavity across a defined stable-shot window to verify consistency. |
Stable-shot weight trend and cavity-balance record |
|
Warpage & Assembly Flatness, sealing & mating fit |
Fixture / Mating Part / Functional Gauge Verified against released mating conditions where applicable. |
Assembly-fit or functional-gauge result record |
| Parameter Category | Why It Matters (Engineering Purpose) | Required Format | Typical Timing | Decision Support |
|---|---|---|---|---|
| Barrel Temperatures | Controls resin viscosity, drying consistency, and thermal degradation risk. | °C per zone (Actuals) | Stable State | Resin stability check |
| Mold Temp & Cooling | Determines part shrinkage, warpage, and cycle time stability. | °C Circuit / Flow Log | Thermal Equilibrium | Dimensional stability |
| Injection & Packing | Records injection speed, V/P position, and hold pressure to control fill balance. | Speed / Position / PSI | Interval-based | Flash & fill control |
| Sample Weight Trend | Recorded by cavity to verify process repeatability and balance. | Grams (0.001g) | Stable-Shot Window | Cavity balance check |
| Stable-Shot ID |
Links sampling window to condition-sheet version for full traceability.
→ process window study |
Unique Sequence Label | Sample Retention | FAI traceability |
| Abnormal Events | Documents machine alarms, downtime, purge events, and manual restarts. | Narrative / Timestamp | Real-time | Stability audit |
The one-page engineering master summarizes required outputs, timing, and release gates for T1, T2, and pilot reviews.
Download Trial Deliverables PDFFull machine setup parameters including barrel temperatures, V/P switchover position, hold pressure/time, and cycle times used for process window freezing.
High-resolution photos of samples with clear cavity-specific tags and labels, ensuring absolute data-to-part traceability for steel-safe reviews.
Comprehensive measurement data for Critical-to-Quality features against the released drawing revision, including ballooned first article inspections.
→ first article inspection report for molded CTQ dimensionsMapping of weld lines, sink marks, or flash with engineering analysis of probable causes and stability impact across all cavities.
Formal list of required tool adjustments with specific steel-safe or metal-off recommendations and assigned action owners for the next stage.
Statistical evidence (Cpk/Ppk) and production-level validation documents required for automotive, medical, or high-precision industrial programs.
→ PPAP document requirements after pilot validationTechnical conclusions regarding tool approval or steel-safe modifications cannot be verified without these deliverables. Decisions made without a frozen condition sheet or cavity-specific FAI data frequently result in hidden assembly failures and process instability during mass production.
This workflow shows what a buyer or remote project manager should receive before, during, and after each sampling stage to verify trial control, traceability, and release readiness.
Confirm that the tool status, resin lot, drying record, drawing revision, and inspection scope are frozen before the trial starts. No sampling should proceed with uncontrolled inputs.
Monitor the short-shot sequence, filling balance, V/P switchover baseline, and early process-window stability instead of judging the run by quantity alone.
Retain cavity-tagged samples only after thermal equilibrium and a defined stable-shot window are confirmed to ensure dimensional stability.
Close the trial with corrective actions. Each issue should be assigned to a steel-safe change, process adjustment, or specific next-trial verification owner.
Poorly controlled trial data creates false approvals and incorrect steel-safe decisions. If the sampling process lacks discipline, resulting measurements can drive unnecessary corrections, create rework risk, and delay final mold release.
Using a non-approved resin grade, lot, or drying condition distorts shrinkage and viscosity. T1 data becomes irrelevant for production validation without verified material control.
Sampling without a Critical-to-Quality list causes the lab to miss critical fit, sealing, or assembly interfaces, producing an incomplete and potentially misleading approval decision.
If cavity ID is lost between retained samples and dimensional reports, Correcting mold steel based on average measurements leads to multi-cavity inconsistency and rework.
Measuring parts before thermal equilibrium or outside the defined stable-shot window creates a false approval risk, as dimensions will shift once production heat stabilizes.
→ run-off checklist for stage-by-stage trial readinessWithout a condition sheet or recorded process settings linked to the retained samples, the process window cannot be repeated, audited, or transferred from T1 to T2.
→ trial record & condition sheet templateTexture release or capability studies should not begin until T1 dimensions are steel-safe frozen. Post-texture welding or steel cutting damages approved surface quality.
No. Dimensional data without a CTQ focus is incomplete for engineering decision-making. Defining tolerance priorities before the trial prevents the lab from passing non-critical features while overlooking assembly risks, which leads to an inaccurate release decision.
T0 samples are produced primarily to test tool function. Because cooling flow, final shrink behavior, and released mating conditions have not yet been validated, T0 parts do not yet reflect the stable geometry required for reliable assembly or fixture validation.
Provides a step-by-step checklist of request inputs, stable-shot review logic, inspection scope, and required post-trial deliverables needed for off-site verification.
Use it before sampling, during T1/T2 review, or before corrective-action release to confirm request inputs, condition-sheet logic, and approval boundaries are aligned.
Essential for procurement leads, tooling engineers, quality reviewers, and remote project managers before approving sample release, tool shipment, or the next trial stage.
We review trial inputs, condition-sheet logic, CTQ scope, and sampling records to ensure your project sampling is governed by engineering evidence. Upload your CAD, released drawing revision, or current T1 package for review.
Review of pre-trial inputs and known tooling constraints.
T1 Package AuditRequires condition sheet, cavity-tagged samples, FAI, and issue list.
