Choosing uniform fabric for a 60-pinafore school tender
A tailoring unit in Dharwad has won a tender to supply 60 school pinafores to a local school. Each pinafore needs 1.60 m of 112 cm-wide fabric after cutting, and the unit adds 8% for wastage. The school's purchase committee has fixed a fabric budget of ₹150 per metre and asks for fabric that is durable, easy-care and comfortable enough for daily wear and weekly washing by children aged 11–14. The supplier offers three options: (a) 100% cotton poplin, 40s count, ₹180/m, 4% shrinkage, needs hot ironing; (b) polyester-cotton 67/33 poplin, ₹140/m, 1% shrinkage, good strength but slightly warmer; (c) 100% viscose rayon, ₹110/m, 6% shrinkage, soft but low wet strength and prone to pilling. A sample pinafore has already been made in option (b); the buyer liked the handle but worried about heat. The unit must choose the fabric, calculate the fabric cost and state care instructions before placing the order.
1. Evaluate the three fabrics against the school's criteria. Calculate the total fabric cost for each option and recommend one, giving at least three reasons.
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First convert the requirement into a purchase quantity: 60 pinafores × 1.60 m = 96.0 m; add 8% wastage → 96 × 1.08 = 103.68 m. At the quoted prices the fabric bill would be: cotton poplin 103.68 × ₹180 = ₹18,662; poly-cotton 103.68 × ₹140 = ₹14,515; viscose 103.68 × ₹110 = ₹11,405.
The school's budget of ₹150/m immediately rules out the cotton poplin. Viscose is cheapest, but it fails the durability test: 6% shrinkage means roughly 5.8 m of the 96 m would be lost in first wash, wet strength is low, and pilling will show quickly at the pocket and hem. Poly-cotton 67/33 has only 1% shrinkage, good abrasion resistance and needs little ironing; its weakness is warmth and a slightly synthetic handle.
For Karnataka classroom conditions I would recommend a cotton-rich poly-cotton (at least 60% cotton, such as 60/40 or 65/35) with a soft finish at a price between the two, because it keeps most of the easy-care performance while reducing the heat complaint. If only 67/33 is available, choose it but specify a finer yarn and breathable finish; do not choose 100% polyester. The decision should be based on cost per wear and replacement risk, not only on the lowest initial bill.
2. The school later insists on 100% cotton for skin comfort. What changes would you make to fabric preparation, pattern and construction to control shrinkage and seam quality?
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Buy a sanforised or compact cotton rather than a loom-state poplin, and pre-shrink a sample before bulk cutting. Even with sanforising, allow for residual shrinkage: add 4% to both length and width when drafting or when selecting size. The revised consumption becomes 1.60 × 1.04 = 1.664 m per pinafore, so order 60 × 1.664 × 1.08 = 107.8 m, not 103.68 m. Check the pattern's armhole and neckline after the shrinkage allowance because a 4% width increase can make the neckline gape if it is added only at the side seams.
For construction, use a fine 2-ply cotton thread, a size 11 needle and 12–14 stitches per inch. Finish raw edges with an overlock or a French seam on the pocket and hem; press seams after stitching. Pre-wash and dry the cut parts before final stitching if the fabric is not fully pre-shrunk. State 'wash before first use' only if the fabric has not been pre-shrunk; otherwise give normal machine-wash care. The key reasoning is that cotton shrinkage is not uniform, so allowance, fabric preparation and seam pressing must be treated together.
3. Write the care label instructions for the recommended poly-cotton pinafore and name two tests you would use to verify the fabric before bulk purchase.
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A suitable label would read: 'Machine wash 40°C with mild detergent; do not bleach; tumble dry low or line dry in shade; warm iron on reverse; wash dark colours separately.' The label must match the fibre blend because a poly-cotton garment scorches at a higher iron temperature than cotton, and chlorine bleach yellows some optical brighteners.
Before bulk purchase, test dimensional stability by washing and drying a 50 cm × 50 cm sample to the labelled conditions and measuring length and width change; the 1% claimed shrinkage should be verified, not assumed. Test colour fastness to washing and to rubbing, especially on the dark school colour, because a uniform that bleeds onto white shirts creates rejected lots. A third useful check is pilling resistance after 2,000 rubs, since the pocket and hem are high-abrasion areas. Record the results on the purchase order so the supplier is bound to the tested performance.