There are two main objectives to swatching, the first is design, and the second is gauge. Take all the time you need with this step, time spent here is never wasted and will save you hours of mis-knitting.
Think about the properties you require for your garment, do you want a loose, drapey fabric or something thick and firm? These properties affect the type of yarn and the needle size you will choose.
Design swatch basics:
- Using the suggested needle size for your yarn, cast on a minimum of 20 st (preferably more) and work a few repeats of your chosen stitch pattern (at least 20 rows). Examine the work and decide if the pattern is to your liking, if not what needs to change? Needle size? Colour combination? A new stitch pattern? Keep experimenting until your fabric meets your expectations.
- Be flexible and open to ideas, try lots of different st patterns or colour combos, think about what may be going wrong and how you may be able to fix it, can you add a couple of rows of garter between the rows of the stitch pattern? Can you make use of a website like Kuler or Colourlovers to get some colourway ideas? Remember common colour issues like colour dominance in fairisle and tonal compatibility.
- There may be some technical issues standing between you and your perfect swatch, “you don't know what you don't know” so don't be hard on yourself, just get out the knitting technique books, ask on Ravelry, ask your friends or the staff at your LYS.
- When you are happy with your design swatch it is time to knit your gauge swatch.
Gauge swatch basics:
- Using your chosen needle size, cast on with a smooth, plain yarn in a similar weight to the yarn you are going to swatch, cast on a minimum 40 stitches work 2 rows stocking stitch in this (waste) yarn. Using waste yarn ensures that your swatch is not distorted by casting on and off.
- Weigh your swatch yarn skein before starting, note the weight of the skein, and the size of needle you are using
- Start knitting with your swatch yarn, leave a 5 cm tail.
- Work in your chosen stitch pattern for a minimum of 40 rows (write down the number of rows). You want to ensure you have completed at least 2 repeats of any pattern widthwise and lengthwise.
- Work 2 rows in your waste yarn (don't cast off yet).
- Examine your swatch, is it the type of fabric you were hoping for? If it is you can skip to step 9, if not continue.
- Change to a larger needle (use your judgement to decide how many sizes to go up to get a looser fabric or down to get a firmer fabric) and work another 2 rows in waste yarn.
- Repeat steps 2-7 until you have a fabric you are happy with.
- Work 2 rows stst in waste yarn and then cast off.
(laundered swatch bottom (not blocked, just patted into shape), unlaundered swatch top.
- Launder your swatch using the method suggested by the yarn manufacturer, if the suggestion is to machine wash use little safety pins to pin all of the yarn ends to the swatch and launder in a laundry bag or pillowcase.
- Pat the swatch out on a towel, and leave to air dry.
- Does the fabric still meet your expectations? Has it become denser or loftier, repeat steps 1-11 until it is right.
- Measure your swatch.
- Repeat for all elements of the garment e.g. If you are working a fairisle yoke with a stst body you will need to swatch both fabrics.
Measuring the swatch
- Ensure that your ruler / measuring tape is correct.
- Lay your laundered swatch out flat on a firm surface.
- Place a pin a few sts in from the edge, measure 10 cm and place another pin, count the number of stitches in the “course”(line of stitches).
- Repeat this with the rows, ensure you count the sts within the “wale” (column of sts).
- Measure again.
- If the swatch you want to measure is quite difficult i.e. A lace pattern where you cant discern sts and rows, you can use the “whole swatch” method of last resort as follows.
- Measure the entire width of the swatch, divide the number of sts by this number e.g. 40 sts / 20cm = 2sts per cm.
- Measure the entire length of the swatch, divide the number of rows by this number e.g. 40 rows / 8 cm = 5 rows per cm.
- I prefer the first method as the end sts can become quite distorted depending on the stitch pattern, but the whole swatch definitely has its merits for complex st patterns.
- I often staple the yarn ballband to the swatch, and write the gauge, needle size and any other info on the ballband.
- Keep all of your swatches, you will develop favourite methods, stitch patterns and yarns, being able to refer to previous swatches will save you a lot of time in the future.