Successful yarn substitutions
Updated: Feb 9
Knitters tend to fall into two categories when it comes to choosing yarn for a pattern – either sticking religiously to the yarn listed in the pattern or the gung-ho “I’m sure this will work” approach.
There is nothing wrong with choosing a different yarn for a pattern – within reason. Substituting laceweight alpaca for aranweight cotton might prove a step too far!
There are plenty of reasons why you might want to substitute a yarn for the one listed in the pattern, such as:
The yarn has been discontinued or it isn’t sold where you love.
You have chosen the pattern to go with some stash yarn
You can’t afford the yarn in the pattern.
You really want the item in a particular colour which isn’t available in the listed yarn.
You don’t enjoy knitting with the recommended yarn
The key is working out whether your chosen yarn will make a good substitute or what to look for in a replacement. There are a few guidelines that will help you work this out.
The fibres in the recommended yarn: When you are substituting a yarn you want your replacement yarn to behave in a similar way to the original. This is easiest if you decide on a yarn that's made up from similar fibres as the recommended one. Wool and cotton behave very differently so swapping one for another will change how the pattern comes out. To see the difference, find a stitch pattern you like and knit two swatches of it, one in cotton and one in wool or a wool rich blend. You will see that the wool swatch has a lot more spring than the cotton one. A wool or mainly wool blend, can usually be replaced with a wool-effect acrylic yarn because these are design to behave like wool. You can usually find the fibre information for the original yarn in the pattern and for possible substitutes check the yarn label or look online.·
Yarn thickness If your chosen pattern is written for 4-ply yarn, you will end up with a very different fabric is you try to knit it in aran for example. Although you can adapt a pattern for a different yarn weight, you are best substituting 4-ply for 4-ply. DK for DK, chunky for chunky, etc. It is possible to adapt a pattern for a different yarn weight but it will need quite a bit of maths and often ends up as a full rewrite of the pattern.
Tension One of the big questions is whether you can get your chosen yarn to work to the same tension as the pattern. There are two steps to this. First, check the recommended tension for your substitute yarn, if it is very different to the recommended tension for the original yarn – this information is usually available on yarn labels or online. If your original yarn has a recommended stitch tension of 22 stitches to 10cm and your replacement yarn has 17 stitches to 10cm you may run into trouble. If the recommended tensions are similar, do a tension square to see if you can match the tension given in the pattern using the needles and stitch pattern listed. There is plenty of advice on tension squares and achieving the correct gauge in Knit School.
If you are happy with the composition of your yarn, its thickness and the tension, you then need to work out how many balls/skeins of your substitute yarn are required.
This takes us back to the yarn label or checking the yarn online again. You need to know the “meterage” or “yardage” of your yarn. That is how many meters or yards there are to one ball of yarn. You may well find that this is different between the original yarn and the one you plan to use. So you will need to work out the total number of meters/yards needed for your project.
This does mean doing a small calculation.
What is the meterage of the original yarn? (A)
How many balls are needed for your size? (B)
To work out the total number of meters needed for your project you multiply the meterage by the number of balls = A times B = M
What is the meterage of the new yarn? (C)
To work out the number of balls of the new yarn needed, you divide the total number of meters required by the meterage of the new yarn = M/C
The pattern requires eight balls of yarn with 115m per 50g.
8 x 115 = 920m
Your chosen yarn has 220m in 100g balls.
Four balls would give you 880m, so not quite enough and five would be 1100m (920/220 gives 4.18 balls).
It is always better to have yarn left over than running out when you are almost finished.
Now you know the basic rules for substituting yarn, there are plenty of opportunities for you to be creative with colour and yarns to create the knitted items you want with a good chance of a successful outcome.
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