Last updated: 2026-09-02 · 5 min read

What Should a Mold Trial Report Contain — Line by Line?

A mold trial report is the tool’s birth certificate: it must record the mold identity, the machine and process as run, the parts produced with their measurements, the issues found with their causes, and the disposition — what passes, what gets corrected, and who owns it. A report missing any of those five blocks is not a record; it is an alibi. The line-by-line list below is what to demand from every trial, T1 onward.

Flash — Thin excess material that escapes between the mold parting line or around ejector pins. Cause: insufficient clamp force, worn parting line, excessive injection pressure, or contaminated mold surface. Flash thickness: 0.02–0.1mm. Requires secondary trimming to remove. See also related guide.

Key Facts

  • Identity first: mold number, cavity count, steel grades, mold base standard, date, machine ID and tonnage. Every later document — corrections, revisions, spare orders — hangs off this header, which is why a report without it cannot join the tool’s file.
  • Process as run, not as planned: melt temperature set and measured, mold temperatures per circuit, cycle time breakdown, cushion at start and end of the run, hold profile. If the report only carries setpoints, you cannot reproduce or troubleshoot anything later.
  • The disposition is the contract moment: every issue found gets a cause, an owner, a correction method and a re-check plan. This block is what converts a trial from an event into a step in a program.

    • Flash — Thin excess material that escapes between the mold parting line or around ejector pins. Cause: insufficient clamp force, worn parting line, excessive injection pressure, or contaminated mold surface. Flash thickness: 0.02–0.1mm. Requires secondary trimming to remove. The related guide covers adjacent topics.

    The Report, Block by Block

    Block Must Contain Why It Matters
    Header Mold ID, cavity count, steel and mold base, resin grade and lot, machine ID, date, attendees Anchors the report to the physical tool and the material state
    Process record Melt and mold temperatures as measured, cycle segments, cushion trend, hold profile, shot weight Makes the trial reproducible and diagnosable
    Parts and measurements Dimensional results on named dimensions versus drawing, weights per cavity, defect counts Turns impressions into evidence with per-cavity resolution
    Findings Each issue with photos, location, severity, and a specific cause statement Separates correction work from opinion
    Disposition Owner per issue, correction method, re-check plan, sign-off by both sides Closes the loop and fixes responsibility

    The Lines Buyers Most Often Regret Missing

  • Cushion at start and end of the run — the one number that later explains weight drift or check-ring wear.
  • Per-cavity shot weights, not just total — the fastest way to see imbalance that dimension tables hide.
  • Mold temperature per circuit, measured on the steel, not read off the controller display.
  • The dimensional table with named dimensions and both numbers: measured value and drawing value, per cavity.
  • Photo or video evidence with the mold number and timestamp visible, especially for cosmetic findings.
  • The vent map marked up with which vents were opened during the trial and by how much.

    • How to Demand It Without Friction

    1

    Put the report template in the RFQ

    Attach the block list above to the quotation stage. Suppliers who build to a known reporting standard price it in; suppliers who resist a template are telling you how the whole program will communicate.

    2

    Name the dimensions before T1

    The dimensional table is only as strong as its dimension list. Agree which dimensions the trial must measure — the ones that decide fit, function and cosmetics — so the report answers your drawing rather than a generic checklist.

    3

    Review the draft before the press cools

    Read the report within a day of the trial while memories are fresh. Errors and gaps found immediately cost an email; the same gaps found at disposition become disputes.

    4

    File it under the mold number

    Trial reports join the tool’s history — with baselines, maintenance and revisions. A report that cannot be found in three years might as well not exist.

    Frequently Asked Questions

    How long should a trial report be?

    As long as the five blocks require and no longer — typically a handful of pages plus attachments. Thickness is not the goal; completeness of the identity, process, measurement, findings and disposition blocks is. A 40-page photo album without a cushion record is still an empty report.

    Who writes the report?

    The mold maker drafts it — they own the trial and the tool data — and the buyer countersigns the disposition. The signature is what makes the cause statements and the correction plan binding for both sides, which is exactly why the disposition block exists.

    Does every trial need full dimensional measurement?

    Every gate that decides the next step does: T1 fully, correction trials on the corrected dimensions plus a spot-check set, and process-only trials on weights and key dimensions. What varies is the list length, never the principle that measurements come named, numbered and compared to the drawing.

    Key Takeaways

    1. Five blocks make a trial report: identity, process as run, named measurements, findings with causes, and a signed disposition.
    2. The highest-value lines are the ones buyers forget to ask for — cushion trend, per-cavity weights, steel-side temperatures, vent markups.
    3. Put the template in the RFQ, name the dimensions before T1, and file every report under the mold number so the tool’s history compounds.

    aCatMould issues every trial report against exactly this block structure — identity, process, measurements, findings, disposition — with per-cavity weights and the cushion trend included as standard, so the document you receive at T1 is the same document that will settle questions in year three.

    Sources
    MoldMaking Technology — trial documentation practice
    Plastics Technology — process documentation
    Kistler — molding process monitoring

    Sources: Plastics Technology · Plastics Technology Online · Society of Plastics Engineers (SPE) · ThomasNet