Spandex is a man-made elastic fiber. It is derived from crude oil and is described in chemical terms as segmented polyurethane. It stretches under tension and recovers its original length when tension is relaxed. It can be stretched four to seven times its original length. It is combined with other ‘hard’ yarns to produce elastane stretch fabrics.
Essentially, Lycra® and Spandex are the same thing. Lycra® is a brand name. Spandex is the generic name used in the US and Canada for elastane. Elastane is the name used in the rest of the world.
KNITTED STRETCH FABRICS
1-Way Stretch (Circular Knits)
Circular knits containing spandex have maximum stretch in the width direction and limited stretch in the length direction. Cotton Spandex jersey is a common stretch circular knit.
2-Way Stretch (Warp Knit Raschel)
Raschel warp knits containing spandex have maximum elasticity in the length direction (warp) and limited stretch in the width (weft or fill). Raschels, Satins, power-nets and laces are all common raschel fabrics.
4-Way stretch (Warp knit Tricot)
Tricot warp knits stretch in all directions. They are eminently suitable for swimwear, costumes, body wear and active wear.
WASHING INSTRUCTIONS FOR SPANDEX CONTAINING FABRICS
Heat and light are the enemies of all stretch fabrics. Elastane yarns degrade over time when exposed to heat and light. Stretch fabrics should be treated with great care to ensure long-lasting comfort and performance.
Categories of yarn, gauge ranges, and recommended needle and hook sizes
Yarn Weight Symbol
& Category Names
Sock, Fingering, Baby
Stitch to 4 inches
6 sts and fewer
12.75 mm and larger
1 to 3
3 to 5
5 to 7
7 to 9
9 to 11
to 4 inch
6 sts and fewer
Hook in Metric
6, 7, 8
K–10 1⁄2 to
* GUIDELINES ONLY: The above reflect the most commonly used gauges and needle or hook sizes for specific yarn categories.** Lace weight yarns are usually knitted or crocheted on larger needles and hooks to create lacy, openwork patterns. Accordingly, a gauge range is difficult to determine. Always follow the gauge stated in your pattern.*** Steel crochet hooks are sized differently from regular hooks—the higher the number, the smaller the hook, which is the reverse of regular hook sizing
Spandex also known as lycra, elastane is known for its exceptional elasticity. It is a very needed fiber for knitters and crocheters as it gives memory to the yarn and takes care of the loose parts (like bottoms of sleeves, or ribbon on a sweater).
Lycra only works with applied heat. When you press or steam the area containing lycra, it will visibly shrink, gathering the texture together. Try it on swatches first: you won’t believe the result. If your garment looks a little stretched after a while, just apply a puff of hot steam to the lycra area and it will be like new.
You can use it stranded with wool as well as with all cellulose fibers (cotton, rayon, linen, tencel, etc…) and silk. Do not change your gauge if you are only using it on a limited area. With wool, you will need to be cautious when applying heat, as you will want to shrink the lycra without felting the wool.
Sometimes, especially with a bigger or heavier yarn, you may want to use two ends of lycra alongside it, to give it a stronger elasticity.