Swatching and sampling are often seen as a chore, skipped by many. When I am asked, how much yarn and what needles or hooks are needed, I explain that not all yarns are the same. Each maker works at a slightly different tension, so a swatch/ sample/ tension square is needed. There is often some eye rolling received at this explanation. And replies of, “I just want to start knitting…”
What is a Swatch?
A swatch is more than a tension square, it is an opportunity to learn about the yarn and how it works.
- Is it pleasant to knit with?
- Is it sticky?
- Squeaky?
- Is it easy to pull out?
- To use grippy or slippy needles?
- Do the colours work well together?
- Will the pattern stitch work in the round and flat?
- Does the fabric drape?
- Is the fabric stretchy or firm?
- Is the yarn colourfast?
- How much yarn for the complete project?
I like to swatch to see how colours work together, swapping colours around, experimenting with combinations. Swatching can be a lot of fun. Often I will make significant changes to a project based on my swatches.
Tension Square
A swatch is also a tension square, a square of knitting or crochet worked to gauge (measure) the tension required to accurately replicate a pattern. A pattern will state a recommended tension, the number of stitches and rows for a 10 cm square of knitting or crochet, using a specified stitch. Working a tension square of at least 15 cm square, ensures a large enough sample for an accurate measurement.
Washing prior to measuring is important as the fabric may change with washing. It would be devastating to spend hours making a garment only to wash it the first time and not have it fit anymore or have the colours bleed into each other.
The weight of a tension square gives how much yarn is required in a project. If a tension square 20 cm by 20 cm weights 30 gms, then a piece 100cm by 100cm needs 750gms of yarn.
Why check guage?
If the tension is just a couple of stitches out over the 10 cms this will result in a garment being too small or too big.
A piece knitted at a gauge of 22 stitches and 30 rows per 10 cms, the tension specified for 8ply yarn on 4mm needles over stocking stitch. Working 220 st over 300 rows would result in a piece 100 cms by 100cm. If the piece is worked at 20 stitches and 28 rows for 10 cm and 220 stitches were cast on the garment would end up being 110 cms, 10cms wider than required and 7cms longer. To adjust the tension a smaller needle, probably 3.75mm would be needed. Knitting another tension swatch would check this adjustment was correct.
If there are too few stitches in a swatch, this is loose tension; too many, the tension is tight.
- Adjust for loose tension – use a smaller needle or hook.,
- Adjust for tight tension – use a larger hook or needle.
Knitting in the round.
When knitting in the round a swatch needs to be knit in the round. Many knitters tensions are different when working in the round and flat. When stocking stitch is knit in the round only the knit stitch is worked. When stocking stitch is worked in the flat, a row or purl is alternated with a row of knit. This difference alters many knitters tension.
Do you swatch? If not why not?