A T1 sample is the first formal trial submission from new die casting tooling. Supplier terminology varies, but its purpose is to determine whether the tool, process, and part are ready for the next decision. Approval should not be based on appearance alone and does not automatically release machining, finishing, or mass production.
This T1 sample approval checklist helps buyers review the submission, inspect critical features, classify findings, and establish a controlled baseline. Resolve open design risks with a die casting DFM review before steel is cut.
What Should Buyers Receive With T1 Samples?
Agree the sample quantity before the tooling trial, or mold trial, so it covers the required dimensional, machining, coating, assembly, functional, or destructive checks.
Each T1 submission should be traceable. Ask the supplier to identify:
| T1 package item | What to confirm |
|---|---|
| Drawing status | Part number, drawing revision, and approved deviations |
| Material | Alloy and material condition used for the trial |
| Sample identity | T1 status and cavity identification for multi-cavity tooling |
| Part condition | As-cast, trimmed, machined, coated, or otherwise processed |
| Inspection results | Agreed CTQ dimensions, method, and actual findings |
| Known issues | Defects, out-of-tolerance features, open tooling changes, or untested requirements |
A CMM report is useful only when linked to the correct drawing revision and sample. Record any temporary process, substitute alloy, incomplete machining, or unfinished surface; otherwise, the approved condition may not represent production.
What Should Be Checked Before T1 Approval?
Begin with requirements controlling function, assembly, sealing, and customer acceptance. Not every drawing dimension is equally critical.
Dimensions and geometry: Check CTQs, datum relationships, flatness, bore positions, wall thickness, distortion, and trimmed features. Separate dimensions created by the casting tool from those created by CNC machining. Match the measurement method and fixture to the feature.
Surface and cosmetic condition: Review cold shuts, flow lines, blisters, sinks, cracks, flash, gate vestige, ejector-pin marks, and trimming. Define visible zones and viewing conditions. An acceptable raw casting does not prove that polishing, powder coating, plating, or another finish will meet final appearance requirements.
Internal and functional risks: When required, review leak or pressure results, porosity near sealing and machined faces, threads, assembly fit, and structural concerns. Use X-ray, CT scanning, sectioning, or other special inspection only when justified by the drawing, risk, or quality plan. See our die casting inspection methods guide.
Tooling and process condition: Confirm cavity consistency and identified issues involving gates, overflows, vents, cooling, ejection, or trimming. Settings may still be optimized, but unresolved tool-related defects should not be hidden by sorting or temporary rework.
How Should T1 Findings Be Classified?
A useful T1 review ends with an action. Record each finding against the drawing feature, sample, cavity, evidence, responsible party, and closure point.
| Decision | When it applies | Next action |
|---|---|---|
| Approve | Agreed T1 requirements are met | Freeze the accepted baseline and continue |
| Conditional approval | A documented deviation is accepted for a defined stage or quantity | Record limits, responsibility, and expiry |
| Correct and retrial | Tooling or process changes could affect fit, function, appearance, or quality | Complete corrections and submit T2 evidence |
| Engineering decision required | The issue comes from design, material, tolerance, or an unresolved requirement | Buyer and supplier confirm the revised direction |
Revalidation should match what changed. A local ejector adjustment may need a focused surface and dimensional check; a gate, cavity, alloy, or major geometry change may require broader validation. This avoids both under-testing and unnecessary delay.
What Does T1 Approval Actually Release?
T1 approval releases only the reviewed scope. An approved as-cast blank does not approve untested machining; machined dimensions do not confirm coating appearance, leakage, capacity, or long-term stability unless included.
Retain the controlled drawing, approved deviations, inspection records, open actions, and reference samples as agreed. Confirm whether the next milestone is T2, finished-sample approval, FAI, PPAP, pilot production, or mass-production release. These milestones are not interchangeable.
The schedule should state when review begins, who approves changes, and how delays affect the aluminum die casting lead time.
Review Your T1 Sample and Tooling Plan With Yongzhu
Yongzhu supports custom aluminum die casting from drawing review and mold making through trial samples, machining, finishing, and repeat production. For a new tool or unsuccessful T1 submission, send the controlled drawing, inspection results, sample condition, and open issues.
We can review which findings relate to tooling, casting, machining, finishing, or an unresolved project requirement before the next production decision.
Frequently Asked Questions
Is T1 approval the same as First Article Inspection (FAI) or PPAP approval?
No. T1 approval focuses on the initial tooling trial and agreed sample requirements. FAI or PPAP may require additional production-representative parts, process records, capability evidence, and customer-specific documents.
Who should approve a die casting T1 sample?
Approval should come from the person or cross-functional team authorized to accept the drawing, functional, appearance, and quality requirements. Purchasing alone may not have authority to accept a technical deviation.
Must every mold correction be followed by T2 samples?
Not always. The buyer and supplier should decide whether the change affects an approved feature or risk. Significant tooling changes normally require new evidence, while a limited correction may need only focused reinspection.
How long should an approved T1 sample be retained?
Retention should follow the customer agreement, quality system, and program life. Define who keeps the reference sample, how it is identified, and when it may be replaced by a later approved sample.
