Testing Failure on a Navy Poplin Shirt Order
An export house has 5,000 m of 100% cotton poplin, 120 gsm, dyed navy. In-house tests show length shrinkage after one wash at 40°C of 6.5% against a buyer maximum of 3.0%, width shrinkage of 4.2% against 3.0%, colour fastness to rubbing of 3–4 dry against a requirement of 4, and 2–3 wet against a requirement of 3. Fabric pH is 7.8 against a required range of 5.0–7.5. The buyer's approved sample had 3.2% length shrinkage and dry rub fastness of 4. The fabric has already been cut into 1,200 shirt panels before full testing, and 300 shirts have been sewn. The order is 2,000 shirts, shipment is in 15 days, and reorder lead time for dyed fabric is 20 days. The unit has 10 days of sewing capacity and can re-cut 500 shirts from available greige fabric, but only 1,200 m of greige is available and it needs 7 days for dyeing. The buyer will accept a deviation only if performance is verified by an accredited laboratory and the shade is within tolerance.
1. Decide the disposition of the 300 sewn shirts and the 1,200 cut panels. Use the test data and contract requirements; do not simply say reject everything.
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The 300 sewn shirts cannot be shipped as conforming product. Length shrinkage is 6.5% against a 3.0% maximum, dry rub is 3–4 against 4, wet rub is 2–3 against 3, and pH is 7.8 against a maximum of 7.5. At least three requirements fail. Washing the sewn shirts to shrink them is not a safe rework route: the garment would shrink further by about 6.5% in length, altering size and causing puckering, and the pH and rub fastness would not necessarily improve. The realistic disposition is to segregate them as seconds for domestic sale or a discount channel, not for the export order. The 1,200 cut panels are made from the same failing fabric and should not be sewn for export; stop cutting immediately. A buyer deviation is unlikely because shrinkage is more than double the limit, although an accredited laboratory report should still be obtained if the buyer asks for evidence. The 1,200 m of greige fabric can be used only for a partial replacement, not for the full order.
2. Calculate the maximum number of shirts that can be cut from the 1,200 m of greige fabric if marker consumption is 1.55 m per shirt and cutting waste is 8%. Compare this with the shortfall.
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Usable greige fabric = 1,200 × (1 − 0.08) = 1,200 × 0.92 = 1,104 m. Shirts from greige = 1,104 / 1.55 = 712.26, so 712 complete shirts.
The order is 2,000 shirts. The 300 sewn shirts are non-conforming and cannot count towards it. After using all the greige, the shortfall is 2,000 − 712 = 1,288 shirts. To make those 1,288 shirts would require about 1,288 × 1.55 = 1,996 m of usable fabric, or 1,996 / 0.92 = 2,170 m of greige before cutting waste. Since only 1,200 m of greige is available, the unit cannot meet the order from its own stock. It must ask the buyer for an extension, source additional dyed fabric, or air-freight a partial quantity while the balance is made later.
3. Outline a quality plan to prevent recurrence, including testing at the fabric stage and acceptance sampling. Name two tests and the point at which each should be done.
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The control point must move earlier: test and approve fabric before cutting. Inspect each dye lot on a 4-point fabric inspection system and check the shade against an approved shade band. Before cutting, test dimensional stability by a standard wash test, colour fastness to rubbing, and pH. Two specific tests are: length and width shrinkage by a standard home-laundry method at the fabric stage, and dry/wet rub fastness by a standard crockmeter method at the fabric stage. Do not release fabric to cutting until shrinkage is within the buyer's 3.0% limit, rub fastness is at least 4 dry and 3 wet, and pH is 5.0–7.5. Hold a small buffer of every dye lot until the tests are complete. At the garment stage, use an AQL final inspection, for example AQL 2.5 for major defects, and check measurement, shade and puckering after washing. Correct the root causes by compressive shrinking or sanforizing the fabric to control residual shrinkage, improving dye fixation and soaping to raise rub fastness, and neutralizing the fabric to bring pH within range.