Visual checks and tolerance
The best way to ensure the quality of a finished product is to visually check the accuracy and quality of what has been made. These are called quality control (QC)A set of checks intended to ensure that a product will meet the specified customer requirements once it has been manufactured. These procedures are followed before work is complete, as opposed to afterwards. checks.
Quality control checks might be carried out:
- before manufacture to ensure fabric has no faults or misprints
- during manufacture to ensure seams are sewn straight, stitching is even in length and neat
- after manufacture to ensure components are sewn on straight and sewing is strong
Although quality control checks can increase waste, with faulty products being thrown away, if a factory develops a reputation for being reliably high in quality, money is saved in the long term through products being reordered.
In a manufacturing flowchartAlso known as a flow diagram. A diagram that shows the step-by-step flow of an algorithm., quality control checks are placed as decisions in diamonds to show where a step would need repeating if there was a mistake:
Preparation
The following factors need to be considered before garment assembly commences and form part of a factory鈥檚 quality assurance (QA)A set of procedures intended to ensure that a manufactured product meets the specified requirements of the client or customer. procedures, intended to ensure that a manufactured product meets the specified requirements of the client or customer:
- stitch length
- stitch type
- stitch tension
- pressure foot type
- thread type
Accuracy
toleranceThe amount by which a measurement can vary without affecting the ability of the product to be manufactured accurately. in textiles is the amount of acceptable variation from the specified measurement from which you can cut out pattern pieces, add componentA part that when put together makes a product. or sew seams.
seam allowanceThe amount of material between the edge of a fabric and the seam line. is the amount of material between the edge of the fabric and the seam, and it is tested to check it meets the tolerance stated in the manufacturing specificationDocument containing clear and detailed instructions for the manufacture of a product.. In home sewing, seam allowance is generally 1.5 cm, whereas in industry, to save on fabrics, the seam allowance is often 1.0 cm. The toleranceThe amount by which a measurement can vary without affecting the ability of the product to be manufactured accurately. is always minimal - otherwise the product won鈥檛 fit together.
Some seams become bulky once sewn, eg points of collars, and they need to be trimmed so that once turnedThe garment is turned inside out to protect the patterned (best) side of the fabric until completed. and pressed they will sit flat. Trimming of seam allowance is also necessary on curved seams.