core technical principles Flashcards
what are the three main seams?
-plain seam
-french seam
-double-stitched seam
what is a plain seam?
a flat seam which is not seen on the outside of the product but the edges need to be neatened to stop them from fraying
what is a french seam?
a french seam is sewn twice so the edges are enclosed and are not visible on the outside of the product. it is a strong seam useful for fine fabrics as the turnings are hidden. (it can be bulky on thicker fabrics)
what is a double stitched seam?
is a strong and flat seam with all the turnings enclosed. It is visible on the outside of the product so is often used as a decorative feature.
how do you do a plain seam?
-stitch plain seam 10mm from edge. trim seam allowance to 3mm
-turn to right side. press flat. stitch exactly on the seamline 5mm away
(when sewing the fabrics should be wrong sides together)
how do you do a french seam?
-place fabrics wrong sides together and stitch on seamline
-press 5mm under
-press seam open. trim one seam allowance to 5mm
-fold over seamline
-stitch folded edge over
what are pleats?
folds in fabric that are stitched or pressed in place
they allow for movement in clothing and add texture and a decorative affect
what are the three main types of pleat?
knife, inverted, box
what is a knife pleat?
single folds all facing the same way
what is inverted pleat?
two knife pleats facing each other
what are box pleats?
two knife pleats facing away from each other
what are tucks?
tucks are similar to pleats but narrower and stitched along their length, used as a decorative feature
what does piping do?
-defines and strengthens an edge and can add decoration
how is piping made?
by enclosing a cord in a strip of bias-cut fabric before stitching it into a seam
how are yarns made?
by twisting fibres together
what is plying?
yarns being twisted with other yarns to make them stronger so they can be used for many purposes.
what are sewing threads made from?
ployester fibre
how do you do weaving?
-woven fabrics are made on a loom which interlaces two yarns at right angles to each other
-the warp is fixed in the loom and runs the length of the fabric
-the second set of yarns are the weft yarns. which go horizontally across the loom, weaving in and out of the warp yarns
what are the main actions in weaving?
- shedding: the warp pass through the heddles that are raised to make a space called a shed for the weft threads to pass through
- picking: the weft yarn in carried through the shed in a shuttle, a rapier, a jet of water or air
- beating: a reed pushes the weft yarn into place
- left off: the warp yarns unwound from a beam as the fabric is woven
- take off: the woven fabric wound onto the cloth beam
what are the two types of loom?
shuttle loom- used to make a plain weave
jacquard loom- used to make complex patterns
why are special finishes added to fabrics?
to make them better suited for intended use
how is stain resistance added to a fabric?
-the fabric is sprayed with flurorocarbons that can stop oil and water based stains attaching themselves to the fabric so it stays cleaner for longer
-the finishes are environmentally friendly and biodegrade over time
what are the best known stain resistant finishes?
teflon and scotchgard
what is a nap?
a one-directional raised or brushed surface
