` marker. Import it as-is into Claude / Gemini / any agent: paste this file as base knowledge. Links between concepts are bundle-relative (/labs/x.md). --> --- okf_version: 2.0.0 title: OKF bundle — scope public source: askmojo scope: public concept_counts: output: 1 --- # OKF bundle (scope `public`) Open Knowledge Format v2.0.0 bundle — markdown + YAML frontmatter. The AskMojo database stays the source of truth; this bundle is an exported view filtered by scope. ## Concepts - **output** : 1 ## Indexes - [outputs](/outputs/index.md) --- scope: public --- # Log Historique des changements de visibilité / publication (dates ISO). _Aucun évènement de publication horodaté._ --- type: output title: 8D report CQ-4471, part 774-2210-B resource: /o/09c01269-6f6f-4aac-9926-d1dd47f79fd7 timestamp: '2026-08-18T08:17:17.071Z' visibility: public --- # 8D report CQ-4471, part 774-2210-B # 8D report CQ-4471 | Field | Value | |---|---| | Customer reference | CQ-4471 | | Part | 774-2210-B, bracket, zinc plated | | Batch | L-26-0714 | | Complaint received | 2026-07-29 | | Report issued | 2026-08-08 | | Status | D6 verified, D7 in progress | ## D1. Team, 2026-07-30 - M. Aubert, quality manager. Owner of this 8D, D4 analysis. - J. Ferrand, logistics. Stock hold and quarantine. - S. Nowak, shift B lead, machine CN-06. Process facts and trials. - P. Renaud, maintenance. Brush wear measurement and interval revision. ## D2. Problem description, 2026-07-30 Burr on the 8 mm bore of part 774-2210-B, batch L-26-0714. Detected by the customer on assembly line 3 on 2026-07-29, by hand during fitting. Two operators were cut and the line stopped 40 minutes. Customer sorting found 61 non-conforming parts out of 300 checked, a rate of 20 percent, on a delivery of 4 800 parts shipped 2026-07-16. The burr sits on the intersection of the 8 mm bore and the top face, height measured at 0.15 to 0.30 mm on our retained samples. The drawing requires all edges free of burr. ## D3. Containment, 2026-07-30, still running - 1 240 parts at the customer, 100 percent checked by our sorter on site 2026-07-31, at our cost. 247 non-conforming found and replaced. Sorting records sent per box. - 2 400 parts of the 2026-07-28 delivery held at customer goods-in, released after sort on 2026-08-01. - 3 600 parts of our stock quarantined 2026-07-30, sorted 2026-08-02, 690 scrapped. - 900 parts in work: 100 percent burr check added before packing. - Next three batches on tightened inspection, 20 parts per box on the bore. Lifted 2026-08-07 once D6 verification was accepted. - Delivery list checked: no other customer received batch L-26-0714. ## D4. Root cause, 2026-08-06 **Occurrence.** The deburring brush on machine CN-06 was worn to 14 mm against 22 mm new, a 36 percent filament loss, while still inside its seven day scheduled interval. Trials on retained parts with a new brush produced no burr. Confirmed. The interval is time based with no wear measurement at change, and it was set when CN-06 ran a softer part at half the current volume. Part 774-2210-B moved to CN-06 in March 2026 and the interval was never revisited. Ruled out, with evidence: bore diameter drift (log ML-26-0714, 8.02 to 8.05 mm on 8.00 to 8.10, centred), drill wear (tool log CN06-T14, 1 100 parts on a 4 000 part life, within wear limit). Open: raw material hardness above nominal. Retained coupon not located, so not tested. Hardness check scheduled 2026-08-14 on the next coil from the same supplier lot. This branch stays open. It does not affect D5, which addresses the confirmed causes. **Escape.** Control plan CP-774-2210 rev C carries no burr characteristic on the 8 mm bore. No inspection could have caught the condition. Confirmed by document review. Contributing: sampling of 5 parts per box gives roughly a 33 percent chance per box of catching a 20 percent condition. Inspector conformity to the plan was checked and is not a cause (record IR-26-0714). ## D5. Corrective actions chosen, 2026-08-06 | Cause | Action | Why this one | |---|---|---| | Brush wear inside a time based interval | Move the CN-06 deburring brush to a count based interval of 800 parts, with filament length measured and recorded at every change, reject below 18 mm | Count tracks the wear driver. Time does not, and the volume on this machine has doubled since the interval was set | | Control plan has no burr criterion | Add a burr characteristic on the 8 mm bore to CP-774-2210, tactile check plus 0.05 mm maximum height, and raise sampling to 20 parts per box | The escape cannot be closed by fixing the machine. Nothing was looking for this condition | Alternative considered and rejected: a 100 percent automated burr inspection. Cycle time and cost are out of proportion to a defect that the interval change removes at source. ## D6. Implemented and verified, 2026-08-07 | Action | Effective | Evidence | |---|---|---| | Count based brush interval, 800 parts, wear recorded, 18 mm reject limit | 2026-08-03 | Maintenance plan MP-CN06 rev D. Four changes recorded since, filament at 19 to 20 mm at change, none below limit | | Control plan burr characteristic and sampling at 20 per box | 2026-08-04 | Control plan CP-774-2210 rev D. Three batches run since, 5 400 parts, 240 parts inspected, zero burr found | | Operator instruction on burr check at final inspection | 2026-08-04 | Work instruction WI-INSP-77 rev B, four inspectors signed off | Defect rate on the 8 mm bore since implementation: 0 out of 240 inspected across three batches, against 20 percent on the claimed batch. ## D7. Prevent recurrence, in progress, due 2026-08-21 - PFMEA for 774-2210-B updated: burr at the bore intersection added as a failure mode, detection ranked against the new control. Document PF-774-2210 rev C, issued 2026-08-07. - Extended to similar parts: the six other parts running deburring brushes on CN-06 and CN-07 were reviewed. Four had the same time based interval and no burr criterion. Both changes are being applied to all four, due 2026-08-21. - Lessons learned circulated to methods and maintenance: a consumable interval set for one part does not survive a part change on the same machine. Interval review added to the part transfer checklist, document TC-01 rev B. - Open item carried from D4: raw material hardness check 2026-08-14. If it returns above nominal, this 8D reopens at D4. ## D8. Closure, 2026-08-08 Disciplines D1 to D6 closed. D7 due 2026-08-21, this report is reissued at D7 closure. Closed by M. Aubert, quality manager. Team recognised at the 2026-08-08 production meeting; S. Nowak located the wear pattern that made the occurrence branch testable. --- title: Outputs description: Outputs index count: 1 --- # Outputs - [8D report CQ-4471, part 774-2210-B](/outputs/09c01269-6f6f-4aac-9926-d1dd47f79fd7.md) (`public`)