Most knitters want nothing to do with math. and I truly do get that! unfortunately, there is a lot of math in knitting, we’ve just let other people do it for us, called patterns. and it is the refusal to do math that has a lot of knitters confining themselves to things like blankets, afghans, scarves and shawls, maybe a beanie hat or two, towels, washcloths, all things that don’t require a strict adherence to GAUGE. Because Gauge is all about the math.
We all know the knitter who claims that they can’t knit a sweater or vest, or anything that requires gauge because it never comes out right. Some don’t bother with a gauge swatch, some have changed the type of yarn they are using – because who always can get the specific yarn mentioned in the pattern?!?! – and even with doing gauge swatch it doesn’t come out right.
I’m one of those people who looks at a pattern as a suggestion; as an idea, or for just the decorative stitch involved. I always do the gauge swatch and it NEVER matches the suggested gauge for the pattern – never matches the recommended gauge as it appears on the yarn label (when there is one). If my stitches are right, the rows are not, if the rows are right, the stitches aren’t. For most things, stitches are more important than rows, but rows do count, which is WHY WE NEED MATH. Math will let us adapt the pattern to our swatch rather than trying to adapt our knitting/needles/yarn to the pattern.
And, BTW, I do not sew well, so my preference is to knit a piece rather than do bits and sew them together – which means top down sweaters, knitting the sleeves into the pieces, etc. But that’s an entirely different tutorial!! AND it also means MATH!
First, remember than your phone, your computer, just about every electronic device out there has a built in calculator. and if not, just buy a calculator. You might also want to buy a gram scale (a diet scale works just fine) because we will get into another aspect of math after we get through gauge – and that gram scale will help you figure out how much yarn you have before you dive into some Stash Busting projects – part 2.
a quick aside, why doesn’t the correct gauge swatch equate to the proper pattern result. Because, in part, the gauge swatch is not really big enough, but unless you want to knit an entire panel, it will have to do. As a piece gets heavy, our knitting may change. While some are very very accurate right through a project, I know I get looser in the center of a piece than I am at the edges, unless there is some sort of pattern. Straight garter or stockinette stitch always has me a little loose in the middle. have to consciously loosen up at my edges. Weight of the piece will also change how a piece fits. Laying flat on a towel or your work bench is one thing, putting it on is another, which is part of why I don’t worry much about row gauge. MOST OF ALL, are you the same size body as the person envisioned when they wrote up the design????
AND yarns vary because of color, vat, lot. The science behind why an acrylic of red might have a different gauge than the same weight acrylic, from the same company, in white is beyond me. But its true. Wool yarn from a scottish sheep might be different than the same worsted weight yarn from an American sheep. Not enough to see with our eye, but a fraction different in gauge. So their recommendation of Brown Sheep wool in loden green might yield a different gauge than your doing up the pattern in Cascade wool in blue.
So back to the math. When a pattern says for a size large you need so many yards of material, and so many stitches, it is all based on the math. If your large sweater pattern is for a 40 inch bust, and you are working a pattern with a fine yarn that gauges 8 stitches per inch. 8 x 40 is 320 stitches. and your brain just exploded at the idea of that much knitting! BUT we all know people who do that easily and readily. Just know it won’t be ME. FIRST, step back now. 40 inches for the bust is a CIRCUMFERENCE. We are knitting one panel at a time, or half that, but am going to stick with the 40 inches for easy math. Feel free to replace 40 with 20, or 25, or 36, or what ever number you want to use. Secondly, we have to allow for ease. Positive ease means the sweater will be loose around the bust, negative ease means it will be pulled tight. no ease means it will fit snugly. You are looking at a pattern in a magazine and it is giving you the stitches necessary to make that LARGE for a 40″ bust you know they are already allowing for ease (and often will say how much ease they have allowed) – you can tell by looking at the picture. The sweater is not clinging, nor is it bagging, nor is it stretched to bursting! But what if you want it a little looser? Then you have to ADD stitches to the pattern. If you want it snugger, you have to remove stitches from the pattern. see***
Back to our pattern for the 40″ bust and yarn that has 8 stitches per inch. Well, you love that sweater, you have the 40″ bust, but you want to knit it in a sports weight yarn. FIRST, do your gauge swatch. Cast on your 20 (or 25 or 30 – but never less than 20) stitches and knit according to the pattern. If its a seed stitch, a stockinette stitch or a garter stitch – the gauge will be about the same, but if its any kind of lace or cable, do it***. Now, the pattern will likely say, do your swatch in stockinette even if the design is not – because they have done the math for you. BUT you are making changes, so the best option is to do the swatch in the called upon design***. If you must, and you probably should, do a swatch in the same yarn in stockinette or garter and compare them. See how wide a 20 stitch swatch in stockinette is compared to a 20 stitch swatch in the pattern knit. and then you will understand why I’m saying a change in yarn requires a full understanding of how it is going to affect the pattern overall.
Once you have done your swatch, take it off the needle and measure your gauge. you can use a little gauge measure device, or just a ruler. Do not measure in just one spot. Mostly opt for either the over all gauge, or measure in/towards the middle in a couple of different spots. Matter of fact – measure the stitches per inch individually by the inch AND measure the over all piece. MATH TIME: if the over all piece of 20 stitches is exactly 4 inches, you have 5 stitches per inch (20 divided by 4 = 5). If the swatch is 5 inches, then you have 4 stitches per inch (20 divided by 5 = 4). Sometimes – OFTEN TIMES – you will have inches+; 4 and 1/2 or 4 and 1/4. Those 1/2 and 1/4″ are important, do not forget them! a quarter inch becomes a full stitch for every 4 stitch repeats you do. If you have a 40″ bust and you calculate the number of stitches by rounding down (4 x 40 = 160 instead of 4.25 x 40 = 170) you will be in a for a rude surprise when done as you will actually measure at least 2″ smaller than you wanted . and if it were 1/2 an inch and you rounded down you would be 4″ short!
Lets take the reverse, say your gauge is 4-1/2 stitches per inch, and you have rounded up to 5. You are going to knit 200 stitches (5 x 40″ = 200 stitches instead of 4.5 x 40 = 180) you will have a plus 4″ at the end. Which might not be bad if you wanted something a little baggy.
So please, take the time to do your gauge swatch, and if you are dealing with something relatively plain, you can now adjust your pattern to your gauge instead of adjusting your needle size. This will also allow you to adjust a pattern for a change in yarn – its all based on that gauge.
****you will also, if doing a pattern, remember that you need to keep your stitch count consistent with the pattern repeats for the gauge swatch and for the overall pattern adjustments. So if a pattern repeat is over 7 stitches, you cannot expect it to come out right on 5 stitches (say over a 20 stitch swatch instead of 28). You will adjust your gauge swatch to size easily enough. But translate to your overall pattern, it will change your overall size – and by doing your gauge swatch and knowing the stitches per inch IN PATTERN you can know, before you begin, whether this pattern will work in your chosen yarn.
Exampling this. You’ve done your 7 stitch repeat design swatch on 28 stitches (4 pattern repeats) and your gauge is 5 stitches per inch and you want your 40″ bust = 200 stitches. 200 stitches will NOT allow you even pattern repeats. you need at least 7 stitches for your pattern repeats and on your 40″ bust (7 x 40 = 280 stitches) That is going to make your piece 40 stitches too long, and that won’t do at all. Lets go backwards. at 5 stitches per inch gauge on 40 inches you have 200 stitches. divide by 7 gives you 28.5 pattern repeats. Round that up to 29 pattern repeats -7 x 29= 203 stitches – not an even division of your gauge, but it works at a minuscule increase in size. That’s your pattern. NOW, you will have to do additional math if you are working a 20″ panel – just the front and separately the back. 5 stitch gauge on 20″ equals 100 stitches that’s 14.2 pattern repeats (100 divided by 7). you can reduce that to 14 pattern repeats at 98 stitches (7 x 14), but that’s not going to leave you much for stitching your front and back panels together. Still, it will work if you don’t mind that slight snugness OR you can increase the size of your needles and start your gauge process from the beginning; increasing a size in your needles may put you at 5.25 (5-1/4) stitches per inch and that will be enough to keep your design and fit.
Lets add one extra bit of math here, especially if you are doing a fancy pattern. Most of us women have different hips to bust size. Personally like that LONG sweater so it must go over my bigger butt. Now I have to find a new stitch count that will allow for my butt without my bust being overwhelmed in yarn. If I’m working a fancy pattern, it is very difficult to gradually increase – while a stockinette, garter, or seed stitch is easily done. and do this successfully, you need to measure at what point – what length – do you want to start widening. measure your body, measure your length. If you are knitting in the round, do your increases on the sides. if you are knitting panels, do your increases on the edges and be sure to do them equally for the front and back. you can also just let the front and back hang as unstitched panels from some comfortable point down. OR you can also let the back panel be longer than the front so you have that extra length for coverage when you sit or bend over.
IF you want to keep that lacy pattern and MUST do a bigger butt to bust – consider knitting to a point at the waist, knit several rows in a plain stockinette stitch, slowly increasing your rows until you get where you need to be, then go back to your fancy stitch. for the rest the sweater.
In re-reading this, it seems complex even to me, yet I know its not. Its just that I’ve repeated things and broken them down to step by step and then repeated it again. Go through this slowly. Take a knitting pattern out – from a magazine or from on line, or even one you have done successfully. Look at it from the point of view of changing yarn weight, needle size, or even just calculating what the actual gauge equals in inches for the bust measurement they are quoting so you can see the amount of ease they are offering (that 40″ bust they say this is for may actually knit out to 42″). compare gauge in the stockinette they reference to the actual fancy knit pattern they have you making to see the difference. Re write this in a way you can understand. Then, you will be able to just pick up any yarn that catches your eye and knit pretty much anything you please without having anyone else tell you how it should be.