Technical Talk & Care

Basic technical information about yarn and its care

Key technical terms

We supply this information on each of our Blacker Yarns, and have also produced longer and more detailed information sheets on each of these terms.

  • Length: wool yarn stretches, some types more than others, and the density varies. So a 50g ball, or 100g skein, may be of a different length, even when it’s the same thickness, depending on these variables. See our information sheet, ‘How long is a ball of wool’. Some patterns, particularly those from US designers, give yardage, rather than weight in specifying the yarn quantity required.
  • Specification: the specification of a yarn describes its thickness, amount of twist and the number of plies. Different specifications work in different ways: thicker yarns knit up more quickly than finer ones, while denser or drapier yarns will produce a different fabric to a more bulky and bouncy style. By definition, thicker yarns will have lower yardage for their weight than finer ones. Some of this is also due to the fibre: so yarns from different sheep produce different results: you can go to our Meet the Animals pages for more information.See our more detailed information sheet ‘Yarn weights’.
  • Tension/Gauge: the specification of a yarn gives it a range of tensions and gauges, depending on what size of needles or hooks is used. So a Guernsey yarn is traditionally worked on fine needles and makes a very dense, wind-proof fabric. The tension or gauge is vital to give you the right size in a pattern and you should always try out a swatch to check whether you get the same number of rows and stitches for the same dimensions as the pattern states. If not, you need to alter your tools: larger needles will make the tension looser, and the item larger, while small needles will do the opposite. Do not be afraid to work with two needles one size apart if you need to get an exact tension and your knitting style requires it. The knitter, of course, is the final ingredient in the mix and not only does everyone work at a slightly different tension, but usually they also work their knit and purl stitches at differing tensions.
  • Knitting needles: there are plenty of charts showing knitting needle and crochet needle sizes because naturally they differ in different places across the world. Needles may also be single pointed, double pointed or circular and both hooks and needles are made of various materials.See our basic info sheet ‘Needles and Hooks’which lists in mm, UK and US sizes.
Caring for wool, mohair and alpaca
We provide indicative and brief guidelines in most of our patterns on how to care for wool, mohair and alpaca. They are much easier to care for than you might think, and even yarns not treated to make them machine washable (though this only usually means on a wool wash, to be on the safe side) can usually be carefully washed on a wool wash. If in doubt, there’s always dry cleaning!
Indeed, we sometimes attack our woven textiles with a more aggressive wash and tumble dry to soften them. This works for alpaca and mohair, which do not felt as easily as wool.
For fuller instructions on washing wool and yarns, please download our Wool Washing information sheet.
Moths are the big enemy of lovers of wool, mohair and alpaca! They love keratin, the protein from which animal fibres are made. Their larvae need this to grow into adult moths. This is not all moths of course: only the dreaded wool case-bearing moth and its close relatives. However, mice, cats and other creatures will also happily nest in and chew wool. In the end, if you have a serious problem you have to resort to poisons, but there are many steps you can take to avoid or reduce the risk of being attacked by these predators.Please take a look at our ‘Death to Moths’information sheet to begin your personal vendetta
Skip to content