Preparing Fabric For Sewing

PREPARING FABRIC FOR SEWING

INTRODUCTION:

Fabric of any type must be pre treated before cutting to avoid later alterations or damage in the finished garment. The untreated fabric may be of correct size on the first wear, but due to repeated washing it may shrink and be uncomfortable to the wearer. Grain perfection is another factor which may deform the silhoutte of the garment. These factors must be given due considersation before cutting.

IMPORTANCE OF GRAIN:

Grain refers to the direction of yarns in fabric. Woven fabrics are made up of lengthwise and crosswise yarns interlaced at right angles to each other. The lengthwise or warp yarns are usually heavier or strong and highly twisted yarns. The lengthwise direction of the cloth should hang straight down on the figure from the neck to the waist, from the armhole to the elbow, from the waistline to the bottom of the shirt. Grain is important in the small places as well as the main pieces of a garment. It is helpful to have a crosswise grain line drawn on such pattern pieces as sleeves, yokes and collars.

In a well constructed garment, not only should the lengthwise grain run lengthwise on the body but the crosswise grains should be at right angles to the lengthwise grain or parallel to the floor at the base of the neck, across the bust, across the fullest part of the hip, at the base of the sleeve etc. This cannot be achieved if you are using an off grain fabric for cutting. The result will be an ill fitting garment which will wrinkles, lacks balance and is uncomfortable to wear. If a dress design should look balanced on the figure, the right half and left half should be identical in design, shape and grain.

SHRINKAGE:

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.

a. Cotton and Linen:

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.

b. Silk, Rayon and Wool:

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.

c. Closely woven starched cotton:

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.

            STRAIGHTENING OF FABRIC:

a. First Method:

Many times fabric needs to be straightened before the garment is cut out. Draw out a crosswise thread and cut fabric along the thread if the fabric has not been torn from the roll. Then the garment will fit better and hold its shape longer. To see whether it is straight, place it on a large table and make a lengthwise fold down the center to meet both selvedge together smooth out wrinkles. If the two selvedges meet evenly with the side of the table and the raw edges come together even with the ends of the table, then the fabric is straight. If the two edges do not come together and are not even with the end of the table, the material is not straight.

b. Second method:

The second method is by pulling the fabric on the bias. When fabric is pulled on the bias, it stretches. Always pull the corner of the shortest edge moving the hand over a few inches each time. The fabric is given a good, firm pull. Sometimes a partner is necessary to assist straightening the material. Then, each one should pull with a right hand and again

with the left hand. Continue pulling first with one hand and the then the other until the material is straight. Repeat this until the selvedges of the material come together. After this, press the material if the cloth is wrinkled. Dampen it with a damp cloth, press along the lengthwise of the fabric but not in the circle. Use a chair to hold the material so that it does not fall on the floor.

MARKING AND CUTTING FABRIC:

It is necessary to mark all details from the pattern to the cloth, which will be needed during the construction of the garment. Mark these details:

         Seam lines.

        Center front and center back lines.

         Darts

         Fold lines

          Positions for pleats or gathers or Pockets

          Buttonholes and buttons

          Any other special markings used to construct the garment

a. Transferring Pattern Marking:

The fastest and most accurate way to transfer construction details from pattern to cloth is with dressmaker's tracing paper or carbon use a tracing wheel and have the carbon mounted on a heavy cardboard to protect table surfaces. Details should be marked on the wrong side of the cloth where most construction lines are needed. Use white tracing paper wherever possible because it is safe. If carefully handled its mark lasts longer. The pigment in coloured tracing paper leaves a more permanent line. It can usually be removed by scrubbing, but ordinary washing methods and dry cleaning do not always remove it. Test a scrap of your clothes before marking the garment. Garment sections should have been cut with the right sides of the cloth together, or when cut from a single thickness, with the right side up, next to the pattern.

Certain lines, such as those for folds and some kinds of pockets and buttonholes are needed on the right side of the cloth. Make the longest machine stitch called a bast stitch along with the traced lines on the underside of the cloth. Stitch through a single layer. The basting shows the detail on the right side of the cloth.

b. Cutting Fabric:

Keep the ends and sides of the material parallel with table edges at all times so that the grain never shift. Walk around the table for cutting, instead of pulling the material. Moving the pattern and material will shift the grain and result in uneven cutting. Do not pick up the cloth from the table or slip the left hand between the cloth and the table. Hold the left hand down on the pattern close to the cutting edge and cut with long even strokes with right hand. Keep the cutting blade or shears resting on the table. Have the thumb in the round handle and the fingers in the long handle, so that shears will not slice at an angle. Cut with long, smooth strokes with the full length of the shears. Cut exactly even with the cutting edge as indicated on the pattern. Cut notches outward. Two or three notches may be cut as one wide notch. Look over the guide sheet or pattern to find out if extra pieces will be needed in finishing, such as shaped facings, bias binding, striaght bands for cuffs or strips for piped buttonholes.

PATTERN LAYOUT:

Laying Pattern Pieces over the fabric in an economical way is called as pattern layout. This prevents wastage of fabric.

Principles of Pattern Layout:

Some of the principles to be followed while laying patterns:

              Press the fabric as well as the pattern pieces flat before laying the pattern on the fabric.

              Use a large table or any hard flat surface for accommodating the work.

              If an open layout is used, place the fabric right side up on the table. For all other layouts fold the fabric right sides facing and wrong sides out.

              Decide on the best way to fold your cloth this will depend on the width of the cloth, width of your pattern pieces, the type of cloth and design of the garment (whether left and right haves are identical. Whether many pieces have to be cut on fold the garment

(whether left and right halves are identical, whether many pieces have to be cut on fold etc.) The common methods of folding the cloth for laying out pattern pieces are the following.

a. Lengthwise centre fold:

Here the fabric is folded down the middle parallel to the selvedge so that the selvedges come together. This is the most frequently used fold. The layout for a simple frock on this type of fold is illustrated in the figure.

b. Off centre lengthwise fold:

This is used when narrow pieces have to be cut on fold. To ensure that the fold is parallel to the selvedge, mark points measuring the required distance (width of the half pattern including seam allowance) from the selvedges at regular intervals and fold along the markings. The layout for a child's panty on this type of layout is illustrated in the figure.

c. Crosswise centre fold:

This is suitable for materials that are too narrow to accommodate the width of pattern pieces when folded lengthwise.

d. Off centre crosswise fold:

When only a part of the material is required to cut pattern pieces that are too wide for lengthwise fold layout, this type of fold is used.

e. Combination fold:

Here length wise fold and crosswise fold are combined.

f. Open layout:

In this type of layout, the fabric is not folded at all. This is used especially for designs which regain right and left halves to be cut separately.

Make a trial layout by keeping weights or two pins per pattern, to make sure that cloth will be sufficient. Rules 6 to 9 must be borne in mind while making the trial layout.

      Straight grain lines on patterns must be kept parallel to the fabric selvedge. To ensure this, measure and adjust the pattern so that both ends of the straight grain line are the same distance from the selvedge and pin the pattern to the fabric along the grain line arrows.

      Fold lines on the patterns must be kept on folded edges of fabric.

      Leave enough space between patterns for cutting outward notches and marking seam allowance (if the patterns do not include seam allowances). Also make sure that there is enough material left for cutting out belts, facings, etc. for which you may not have made paper patterns.

      The patterns must be placed on the fabric in the most economical way.

      Pin patterns to the fabric firmly, after placement of the pattern has been decided, pin the corners and the long outside edges of the patterns, placing pins close to and approximately perpendicular to the cutting line. Use just enough pins to keep the pattern in position. Too many pins will distort the edges. You should start cutting the fabric only after pinning all the pattern pieces.

          Take care to use special layouts for asymmetric designs and for fabrics with bold designs, striped and checked designs, designs going in one direction and fabrics with nap and pile.