"Right twist – most American
threads are twisted to the right,
causing some rolling. This gives
average stitch quality.
Left twist – Most commercial and
imported threads are twisted to
the left, giving better than average
stitch quality. Left twist resists
rolling and makes a larger loop for
the hook point to enter, reducing
skipped stitches.
Wearable art embellishment has necessitated the creation and
marketing of many new thread types, such as rayons and metallics.
Threads made in West Germany are left twist threads; Mettler and
Isacord threads are also left twist. To test the twist of a thread: while
holding the spool in the left hand, roll the strand of thread towards
you with one thumb. Left twist will tighten, right twist will loosen.
Fiber – refers to the type of material used to produce the thread.
Some commonly used threads:
• Polyester 2 ply – such as Metrosene 100. Good for clothing
construction on man-made, natural or blended fabrics. Will
tolerate heat up to 450° Fahrenheit.
• Polyester 3 ply cordonnet – topstitching or buttonhole twist –
such as Mettler 30/3.
• Cotton 2 ply – such as Mettler 60/2 – excellent for French
Machine Sewing, delicate machine embroidery, piecing and
darning.
• Cotton 2 ply – such as Mettler 30/2 – loose twist for a soft,
shiny look in machine embroidery, applique, and buttonholes.
• Cotton 3 ply – such as Mettler 50/3 – excellent for clothing
construction on natural fibers. Tighter twist than embroidery
cotton thread and less puckering on problem fabrics. Cotton
thread stretches less than polyester.
• Rayon – a lustrous embroidery thread. Weaker than cotton,
it is used for decorative work only.
• Polyester 2 ply embroidery thread – Isacord and Polysheen
embroidery thread – excellent for embroidery, very abrasion
resistant.
Thread Storage
Thread does deteriorate with age and should be stored with care
to keep it usable as long as possible. Extreme moisture may cause
thread to swell while very dry conditions can leave it dry and brittle
as it ages. Store thread in a covered container (thread box with a lid,
cabinet with doors, or drawers that close) if possible to keep it dustfree"