T1 Sample Review Checklist: A Printable Buyer Worksheet

A T1 mold trial requires a structured review. Approving samples based solely on a visual check guarantees downstream production crises. This worksheet operationalizes the mold trial guide; work through it with the physical samples, the 2D drawing, and the supplier’s trial report.

Print this checklist or copy it into your program file, using one sheet per trial. (For an interactive walk-through, use the T1 Review Assistant).

1. Documentation Prerequisites

Do not review physical parts until the supplier provides the corresponding engineering data. Without documentation, you are reviewing a theory, not a repeatable process.

• Trial Metadata Identified: Tool number, T-stage (T1/T2/etc.), date, press tonnage, and active cavity count.
• Dimensional Report Received: Measurements of the T1 parts against the 2D drawing (critical-to-function dimensions at minimum).
• Process Setup Record Received: The exact machine parameters (temperatures, pressures, times) used to mold the submitted samples.
• Supplier’s Issues List Received: The supplier’s own assessment of remaining defects and planned tool corrections.
• Drawing Revision Confirmed: Verify the supplier measured against the current, approved revision of the print.
• Material Certification (CoA): Confirm the exact resin grade and colorant specified were actually used in the trial.

2. Visual and Defect Walkthrough

Inspect parts cavity-by-cavity. Log all findings in the Defect Log Template.

• Fill: Tool fills completely; no short shots in ribs, bosses, or deep corners.
• Flash: No flash present at the parting line, ejector pins, or vents. (If flash and short shots appear on the same part, see short shot and flash T1 review).
• Sink: Sink marks over thick sections (bosses/ribs) are within acceptable cosmetic limits.
• Weld Lines: Weld lines are located away from structural load paths and highly cosmetic A-surfaces.
• Splay/Silver Streaks: No splay indicating wet resin or shear degradation.
• Burn Marks: No burn marks (gas trapping) at the end-of-fill locations.
• Gate Vestige: Gate blush, stress whitening, or excessive vestige height is within defined limits.
• Ejection Marks: Pin push-off marks or drag lines are evaluated (determine if they require a tool fix or are inherent to the geometry).
• Cracking: No cracks or crazing. Any structural crack is an automatic hold.
• Cosmetics: Gloss/texture is consistent; color matches the standard under the agreed light source.
• Warpage: Part sits flat on a reference surface; warpage is within tolerance.

3. Dimensional and Functional Review

• Dimensional Audit: Review the supplier’s dimensional report. List any out-of-tolerance (OOT) dimensions and require a written correction plan (tool steel adjustment vs. process adjustment).
• Cavity-to-Cavity Consistency: For multi-cavity tools, ensure variation between cavities is statistically acceptable.
• Mating Fit: Perform a physical assembly trial with actual mating components.
• Functional Testing: Flex or torque-test loaded features (e.g., snap fits, threaded bosses) on the T1 samples.

4. Process and Cycle Economics

• Cycle Time: Compare the demonstrated T1 cycle time against the quoted cycle time. Require an explanation for any significant gap.
• Ejection: Parts eject automatically without operator intervention (no hand-pulling, no continuous application of mold release spray).
• Process Capability: The provided process record is robust enough to accurately reproduce the run.

5. The Approval Decision

Categorize the trial outcome and formally communicate the status to the supplier.

• Approve: Parts meet all requirements. Findings are minor and documented; quality standards/limit samples are updated.
• Approve with Conditions: Parts are acceptable for limited use. Specific tool or process corrections are listed, owners are assigned, verification dates are set, and a T2 trial is scheduled.
• Hold/Reject: Critical structural findings (cracks, voids in loaded features), unexplained cavity-to-cavity variation, or missing foundational documents. Tool is not authorized for production.

Record the decision, attach the conditions, and require signatures from both engineering and quality. For borderline decisions, consult the Mold Approval Risk Checklist.

Disclaimer

PlasticsTechnologyAlliance.com is an independent buyer resource. This checklist supports, but does not replace, your internal quality procedures and your supplier’s engineering review. Adapt items to your part, industry, and risk level.