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Yarn Substitution

Yarn Substitution
Welcome, Mary Beth Temple our guest author, who is telling you all you need to know about yarn substitution. Love a pattern but the yarn's discontinued? Or perhaps, you'd like to swap the fibre? Read on...
I was selling patterns at crochet and knit show a couple of years back and someone looked at one of them, sighed, and said: “I really love this one but I don’t want a green sweater.” When I told her she could simply use a different colour of the specified yarn she seemed shocked – it simply had not occurred to her.
Changing colour is a simple change to make, but what if you need to make a different sort of change before you begin your project? You have found your dream pattern but it's made in wool and you’re allergic, it's dry clean only and you like to hand wash, it costs the earth and you want to make it more affordable, or the yarn has been discontinued and is no longer available? Welcome to the gentle art of yarn substitution.


There are many reasons why designers choose the yarns they do, some of which are relevant to yarn substitution and some of which are not (the magazine editor made me!). When choosing yarn for your project you need to consider yarn weight, texture, and general appearance.


Yarn weight is a tricky one. Most yarns sold in North America and many sold in Europe have a weight number on the ball band. These weight numbers were established by the Craft Yarn Council of America and range from the finest lace weight (CYCA 0) to the new category for the insanely thick yarns that are popular for crafts like arm knitting and finger knitting (CYCA 7). These weight numbers are just a general guide, however, and it’s important to know that all size 4s, for example, are not interchangeable.
Yarn Weight UK Yarn Weight US Yarn Weight Australia Needle Size Hook Size
1 ply Lace 2 ply 1.25-3mm 0.75-3mm
2 ply Fingering 3 ply 1.25-3.5mm 2-3.5mm
4 ply Sport 5 ply 3.25-4mm 2-3.5mm
DK Light Worsted 8 ply 4-5mm 3.5-4.5mm
Aran Worsted 10 ply 4.5-6mm 5-6.5mm
Chunky Bulky 12-14 ply 5-8mm 6.5-9mm
Super Chunky Super Bulky 16 ply 8-12mm  9-14mm
Super Chunky  Jumbo 20 ply 12mm + 15mm+
The absolute best trick I know for trying to compare the weight of two different, comparable yarns that you are not holding in your hand is this – look at both the yardage and the skein weight on the ball band. If one yarn has 200 meters (or yards for my US friends) in a 50g skein and one has 300, there is going to be a significant difference in the thickness of those two yarns. So if the designer used a yarn that has 135 meters or yards per 50g and you have one that's 145 or so, that’s likely going to be close enough. If the information you have is for a 50g skein for one type and a 100g skein for the other, simply cut the numbers for the 100g skein in half for comparison’s sake. The closer the numbers, the more likely it is that you have a good match in weight.
Next, consider the texture of the yarn. If the yarn has a characteristic in its makeup, to make your project to look like the photo, you need to choose a yarn with similar characteristics. When considering texture you need to think about whether the project yarn has a lot of halo (mohairs or brushed acrylics), a particular spin such as boucle or thick and thin, and even the number of plies it is made up of. Single-ply yarns have a much more rustic look than yarns made of of many plies, which often look smoother, and the fabrics made from single plies often behave differently because they don’t have a twist. The amount of twist affects stitch definition – I might want something smooth and tightly plied for cables or texture stitches, and I generally wouldn’t try to do a pattern with a lot of tricky stitches in a yarn with a lot of halo, or a distinct lack of twist. You’d be stitching away, counting your stitches like a boss but the wrong yarn would make your work look muddy and you might just as well have done double crochet or garter stitch!




One more thing to think of when you are thinking about texture is elasticity. Plant fibres such as linen and cotton behave very differently than acrylics, which behave very differently from animal fibres like wool and alpaca. If you have an allergy to animal fibres I am not suggesting you throw caution to the wind and buy wool anyway. But animal fibres are way more elastic or springy, if you will, than plant fibres, while acrylics can run the gamut depending on how they are made. Look at the qualities of the stitch pattern you want to make – does it need to make a stretchy fabric for fit, or does it need to be stiffer for durability? Pick a yarn that will support your goals.
Scheepjes Catona  Deramores Studio DK


Last I want to talk about appearance. Appearance is what the yarn looks like, as opposed to the texture which addresses how it is made. When speaking of yarn colours, a rose is not always a rose! Do you want a stark solid, a heathered look, or a semi-solid or tonal look? Each one of those will look different when knitted or crocheted up. If it is a multi-coloured yarn, does it have a long, graduated repeat, or is it a mix of short bursts of colours? Those two are usually not interchangeable – in the same way that too fuzzy a texture will defeat a gorgeous stitch pattern, a frantic variegated yarn can obscure a delicate stitch. Save those bold bursts of colour for simpler stitching.

So the next time you see a pattern that you love – you too, can make a red sweater if you don’t want a green one! Consider weight, texture and appearance and find the perfect yarn for the project of your dreams.

Mary Beth Temple