So you have a pattern, you have some really yummy yarn that you know would just look fabulous... but no matter how hard you try, you just can't match the gauge in the pattern.
Or... you found the most wonderful pattern for a hand-knit sweater that you want to make on your knitting machine where even trying to match the HK gauge is probably a waste of time.
These can be very frustrating circumstances, but they're easily overcome if you understand gauge and the very simple math involved in redrafting a pattern to work with your yarn and your style of knitting.
I believe gauge is the most important knitting concept because it is the sole principal that determines whether a knitted item will be the right size when it is finished. For an afghan, you have a bit of leeway in that a slightly smaller or slightly larger afghan is still acceptable. For a sweater however, a mere 1/8" inch difference between the pattern gauge and your knitting gauge is enough to cause an improper fit.
If you've always believed that knitting a swatch is a waste of yarn, think again... you'll waste a lot more yarn knitting an entire sweater that ends up being 3" too small.
To guarantee a good fit, it's important that you follow a few simple steps before you start knitting your item:
- Knit a swatch that's at least 5 inches wide and 6 inches long. The larger your swatch, the more accurate your gauge calculation will be.
- Block and finish the swatch exactly as you will block and finish the knitted article. If you are going to wash and dry the sweater, you must also wash and dry the swatch before taking your gauge measurement.
- Measure the swatch to determine gauge after blocking and finishing.
- If you're working with a particular yarn for the first time and can't approximate the number of stitches and rows required for your 5 x 7 swatch, try 60 stitches by 80 rows for fine yarns, 40 stitches by 60 rows for medium yarns and 20 stitches by 30 rows for bulky yarns.
- Different types of stitches -- stockinette, rib, lace, cables and others -- will have different gauges. If the pattern specifies the gauge for stockinette, your swatch should also be stockinette. Otherwise, your swatchshould incorporate the stitches used in the pattern.
- Do not include the edges when you measure your swatch because they may distort your measurements.
- Always use a knitting ruler or high-quality metal ruler to measure your swatch. Inexpensive wooden and plastic rulers are often inaccurate and tape measures have been known to stretch and shrink with the weather. I use a metal drafting ruler that is known to provide accurate measurements to the nearest 1/16".
- If you're using a very heavy yarn, you may want to knit a longer swatch and let it hang from a clothes hanger overnight. Gravity will sometimes cause knitted garments to stretch in length over the course of time.
Always take measurements to the nearest 1/16".
My Favorite Method For Knitting A Swatch
- Cast on 20 (40,60) stitches with the main yarn and knit 10 (15,20) rows.
- Knit one or two rows of a constrasting yarn that is the same size and fiber content as the main yarn.
- Knit 15 (30,40) rows in the main yarn.
- On the next row, mark the fifth stitch from each edge with a small length of constrasting yarn.
- Knit 15 (30,40) rows in the main yarn.
- Knit one or two rows of constrasting yarn.
- Knit 10 (15,20) rows in the main yarn.
- After blocking and finishing my swatch, I measure between the contrasting rows to obtain rows per inch and between the markers to obtain stitches per inch. This avoids use of the edge stitches and usually results in a more accurate measurement.
Calculating The Gauge Of Your Swatch
The number of stitches ÷ the width of the swatch = stitches per inch:
If the distance between the marker stitches on my swatch is 5" and there are 20 stitches between the markers, my stitch gauge is 4 st = 1": 20 ÷ 5 = 4.
The number of rows ÷ the length of the swatch = rows per inch:
If the distance between the contrasting rows on my swatch is 5" and there are 30 rows between sthe markers, my row gauge is 6 r = 1": 30 ÷ 5 = 6.
I Can't Get Gauge... Now What?
You already know from the explanation above that gauge is merely a means of making sure a knitted article ends up being a particular size. So when you're having trouble getting gauge or contemplating using a substitute yarn, it helps to think of things in terms of inches instead of stitches and rows.
Let's assume that my favorite v-neck pullover pattern calls for a medium weight yarn that yields 20 stitches and 24 rows over 4" (or 10 cm). I can't obtain the recommended yarn, but I have another yummy yarn in my stash that I think would be just fabulous. After knitting, blocking and finishing my swatch, I learn that I get 18 stitches and 21 rows over 4". I might be able to match the gauge more closely by changing my needle size, but I've decided I really like the way the swatch feels as it is and I don't want to give up a softer fabric by switching to smaller needles. So I grab the calculator and start writing my own version of the pattern to work with my yarn and my gauge.
Determining The Number of Stitches to Cast On
First, I need to know how wide the item is supposed to be on the needles. If the pattern contains a schematic that gives me the width, I'm all set. If the pattern gives me gauge and the number of stitches to cast on, I can calculate the width as:
# stitches ÷ stitches per inch = width
In my case, my pattern only says I need to cast on 88 stitches for the front of the sweater... so I need to figure out how wide the piece is supposed to be:
20 ÷ 4 = 5 stitches per inch
88 stitches ÷ 5 stitches per inch = 17.6"
Now that I know the width, I can figure out how many stitches I need to cast on to make the front of my sweater the same size as the pattern using my gauge:
18 ÷ 4 = 4.5 stitches per inch
4.5 stitches per inch x 17.6 inches = 79.2 stitches
Since the number of stitches must be a whole number, I need to cast on either 79 or 80 stitches. If my sweater has a special stitch pattern that must be centered across the front of the sweater, I need to round up to 80 stitches because the original pattern calls for casting on an even number of stitches. Since we should probably have the V in the center of the sweater, I'm going to cast on 80 stitches.
The very next thing I'm going to do is take another look at my pattern. Did you know you can sometimes use the wrong size pattern to make the right size garment? If my pattern provides instructions for different sizes and has instructions that call for casting on 80 stitches, those instructions will knit the width I want using my gauge. I'll simply follow those instructions for everything having to do with the number of stitches: cast on, bind off, number of stitches to decrease or increase, etc. Since this is a basic pullover with a standard amount of ease, I could use any size on the pattern that's close -- casting on 78 or 82 stitches, for example.
Next, I need to know how long the item is supposed to be. Again, if the pattern contains a schematic, I'm all set. Otherwise, I need to calculate the length in exactly the same way I calculated the width:
# rows ÷ rows per inch = length
In my case, the pattern doesn't give me row gauge nor does it have schematics, but it does tell me to "knit until the piece measures 15 inches" and that's all I need to figure out how many rows I need to knit:
length ÷ rows per inch = # rows
21 rows ÷ 4 inches = 5.25 rows per inch
5.25 rows per inch x 15 inches = 78.75 rows
Again, I'll round to the nearest whole number and knit 79 rows
At this point, we've taken care of all the simple calculations. But, how are we supposed to handle arm and neckline shaping or those gradual decreases required for a tapered sleeve? Simple... we'll continue to apply what we've learned above to shape the garment. To illustrate this, I'm going to use a schematic because that will make explaining things a little easier. After we get through an exercise with the schematic, we'll talk about what you do when you don't have one.
Here's the schematic for the front of my sweater. Ant to keep things as simple as possible, we're just going to concentrate on the body of the sweater and not worry about the ribbing that goes around the waist, armholes and neckline:
I'm going to knit this sweater from the bottom up, starting at the waist line and working our way to the shoulders.
Shaping The Waist
The pattern tells us that the width of our knitting needs to increase from 17 1/2" to 19 1/4" over 3" of length:
From before, we know that length ÷ rows per inch = # rows, so 3" of length is 16 rows (15.75 rounded up). We also know that width ÷ stitches per inch = # stitches, so 19 1/4" of width is 86 stitches (86.625 rounded down). If I had cast on an odd number of stitches, I would have rounded up to 87.
We now know we need to increase from 80 to 86 stitches over 16 rows. Since we need to increase on both sides, we'll increase 3 stitches on each side.
There's nothing of any interest for the next 5" -- the distance between the top of the waist and the bottom of the v-neck -- so we'll simply knit straight for 26 rows (5.25 x 5 = 26.25 rounded to nearest whole number).
Shaping The V-Neck
If you're already thinking you know how to do this, you're probably right -- we're going to use the exact same method to shape one side of the neck, putting the other side on hold until we're ready for it. We're not going to go into all the details, but I'll give you a few measurements to start you off:
The distance between the bottom of the v-neck and just below the shoulder is 5 1/4": the pullover is 14 1/4" long (11 1/4" + 3"), the v-neck shaping starts 8" from the bottom of the waist and stops 1" below the shoulder.
The distance between the side of the pullover and the center of the pullover is 9 5/8": 19 1/4" ÷ 2.
You now know you need to decrease from 9 5/8" to 6 1/4" on one side over 5 1/4". Try doing the calculations yourself using the waistline shaping as a guide. If you come up with "decrease 16 stitches evenly over 28 rows"...
Pat yourself on the back and have some chocolate... you earned it!!!