All fabrics have tendency to shrink when dipped into water unless they are pre-shrunk. Excessive shrinkage can ruin the fit of the garment. While stitching, if the cloth has not been pre shrunk extra allowance for shrinkage should be kept. For various types of fabrics different shrinkage treatment has to be given.
If the fabric is white cotton it should be allowed for at least 4 hours in hot water to remove starch. To shrink the cloth uniformly the position of the cloth in vessel should be changed occasionally. For coloured materials luke warm water should be used and the same processes followed as for white fabrics given above. Different coloured fabrics should not be immersed in water together. Each colour should be immersed separately. After the material has been shrunk it should be allowed to dry in shade and should not be squeezed to remove water. The stiff materials like canvas or long cloth etc. should also be shrunk before they are used.
As silk and rayon shrunk very little and slowly, it is not necessary to pre-shrunk them before cutting. Little allowance may be kept while stitching the garment. Woollen materials can be shrunked in two ways.
One method is to steam the materials as follows. The cloth to be treated, should be spread over a table and folded right side facing . Now place a damp Turkish towel between the two layers. Spread an ordinary piece of cloth on the upper side of the cloth, then press it with moderately hot iron. This will provide the necessary steaming. This process should be repeated all over the fabric.
The second method is laying a layer of wet muslin or long cloth over the fabric and rolling the two together and allowing it to remain in this position over night. After this the muslin or long cloth should be removed and the woollen fabric is spread on the table with wrong side upwards. The fabric should now be pressed and allowed to dry naturally.
Dip the fabric into mild soap solution for at least four hours. For uniform shrinkage the position of the cloth should be changed occasionally. It should then be removed and rinsed with cold water 3 to 4 times, and then allowed to dry without squeezing. The cloth should be pressed, before it is completely dry.
Note: 1. In all cases the fabric should be unfolded and then treated for shrinkage.
2. Care should be taken that the bucket or the vessel used is not rusty.