Okay — I swatched some more on this cardigan project. Earlier I had posted about Things Learned from a Swatch. Well, I continued to be dissatisfied with my color selections — I really just do not like that light aqua color for this sweater. So, I went back to my LYS and bought up all the teal color they had — which is the color I really wanted for the main color on the cardigan. The problem is that there isn’t enough of this color to do both a cardigan and a romper to match.
So, standing in front of the yarn bin at the store, I decided that I’d try using a combination of the teal, the red AND a darker blue. There was enough of the darker blue in one dye lot to do the romper and there was 1 ball of another dye lot left. Since I only need 1 ball of the darker color to do the alternating 3 color pattern in the cardigan, I bought this ball as well because the color variation is not that different between the two dye lots and since it will be mixed in with the other colors, it should work out okay.
Here’s my swatch with the new color scheme added. The darker blue color definitely shows up better than the lighter blue against the teal color that I want for the main color. I have started knitting the romper in the darker blue and I think I’m going to really like the coordinated outfit that will result. This project is a bit challenging because I am knitting on size 0 and size 1 needles to get the right guage. Lots and lots of small stitches…
I have covered the basics of how to make a Gauge Swatch and calculate your stitch and row gauge in my previous three posts. Today’s topic will cover some basic math to help you estimate the yardage that you need using your yarn, your needles, and your gauge to make a sweater.
Let’s say you want to make a sweater using yarn from your stash and you need to know if you have enough to make it. To make this estimate, you need the measurements for the sweater you want to make. If you are using a pattern, the finished measurements should be stated within the pattern – ideally on a schematic. Some patterns may only state the desired measurements within the text of the pattern and you may have to read through to find them. If you are making the sweater without using a pattern – you would use the measurements of the individual who will be wearing the sweater.
The image below shows a schematic for the back of a sweater of a drop sleeve sweater. The back is 28 inches long from the hem to the neck and it is 20 inches wide. Both the front and the back of this type of sweater are essentially rectangles.
Schematic of Back/Front of Sweater
The schematic for the sleeves of this sweater are shown below.
Schematic of Sleeve
At this point, you have the numbers you need to calculate the number of square inches of fabric that you need to make for this sweater. For the front and back, multiply the length by the width on the schematic and then multiply that number by 2. Using the numbers from my example above:
20 * 28 = 560 560*2 = 1120 square inches for front and back.
The sleeve is a trapezoid shape. The formula for the area of a trapezoid is:
[(b1+b2) * h] / 2
Where b1 is the width at the bottom of the sleeve(8”) and b2 is the width at the top of the sleeve(15”) and h is the length of the sleeve(18”). Using the numbers from the sleeve schematic, the area for one sleeve is 207 square inches. Since you need two sleeves, you then need to multiply the area of the sleeve by two. (414 square inches)
Now, here’s a short cut – if you place your sleeves next to each other so that the tops of the sleeves are parallel – you have a parallelogram. To get the area of this parallelogram you simply multiple the width(15”+ 8” = 23”) by the length(18”). Try it – you’ll get the same number as above.
Add the square inches for the front and back to the square inches for the sleeves and you have the total number of square inches of fabric in the sweater. Now that you know the total number of square inches of fabric you need, you will need to use the yardage and weight information of the yarn you want to use to estimate how many skeins or balls of yarn your sweater requires. The yardage per weight of the yarn will be found on the yarn label – see image below:
You will use the yards per gram value in the estimate for total yardage. Now you need to knit a swatch. The swatch should be in the same stitch pattern that you plan to use for the body of your sweater. This swatch does not need to be the same size as your gauge swatch, but it should be wide enough and long enough to get an accurate weight, length and width measurement. After you knit this swatch, you will measure its weight using a scale that measures to the nearest tenth (0.1) of a gram. Next measure the length and width of the swatch and multiply these values together. This gives you the number of square inches in your swatch. Now divide the number of grams by the number of square inches.(Do not round). You now know what 1 square inch of your yarn weighs. This is the number you need to calculate how much yardage you need for your sweater.
Example: My swatch measures 3.5 inches by 4.5 inches, which gives me 15.75 square inches. The swatch weighs 9.6 g. Dividing 9.6 by 15.76 gives me 0.622 g/square inch.
Here’s the final set of calculations:
Take the total number of square inches of fabric and multiply it by the number of grams per square inch. This gives you the total weight in grams for your sweater.
Total Number of Square Inches * grams/inch2 = Total grams of fabric
Total Grams/Square Inches = (1120 + 414) * 0.622 = 954.148 g
Now take the yards per gram value from the yarn label. (For example 218 yds/100grams). Divide the yds by the grams to get the number of yards in 1 gram of yarn. (For example: 218yards/100grams = 2.18 yards per gram.) Multiply the total number of grams of fabric by the number of yards per gram to get the total yardage for the sweater. Using the numbers from the examples above:
Yards per gram = 2.18 yds/g
Total Yards of Yarn = 954.148 * 2.18 = 2080 yds
To determine the number of skeins, balls or hanks of yarn you need: Divide the number of yards by the number of yards in the skein. Or divide the total number of grams by the number of grams of the skein. Remember that you will want one extra skein for swatching. (In my example, I would need 9.5 skeins, so I would want 11 skeins with one extra for swatching)
What to do if you don’t have the yarn label
To determine how many yards of yarn you have when you do not have the yarn label or any information, simply measure out 10 yards of your yarn and weigh it. Divide the weight by 10 and you have the weight for 1 yard of yarn. Now weigh the skeins/hanks of yarn and multiply by the weight of 1 yard. This will give you the number of yards for each skein/hank.
I have not been actively blogging since about 2014. Life has a way of intervening from time to time, and I stepped away from the task of updating my blog and website to focus on other things happening in my life.
I just finished updating my website pages with a new theme and color scheme. I have also updated links throughout. As often happens links change over time or become inactive. I hope you find the updates pleasing and that you will continue to check in to my blog from time to time as I plan on making regular posts going forward.
My next post will be the first of a series of posts discussing swatches. Swatches are one of those things that you learn to appreciate over time and I will be sharing what I have learned as I have grown as a knitter.
The subtitle for this book is “mastering fit + plus-size style + 15 projects”. The first two chapters of this book cover the basics of how to knit garments that fit. While the focus is on plus-size, the information is applicable to any knitted garment. The information in these two chapters is worth the price of the book if you are wanting to learn more about how to modify patterns so that they actually fit your body. Chapter One discusses the common elements of a sweater and “what they mean to you” and Chapter Two covers the use of measurements and how to redesign patterns for a custom fit.
The remaining five chapters cover different types of sweater styles: The Drop-Shoulder, the Set-In Sleeve, The Raglan, The Seamless Yoke, and The Dolman. There are three projects for each type and these are really lovely designs for us plus-size gals. Each project also has helpful notes for the knitter. So this book is both a “how-to” guide and a set of 15 plus-size patterns. And some of those patterns are the sort that makes a knitter’s fingers itch to pull out some yarn and needles and get started. The “Poppy Cardigan” on page 67 is on my list of future projects for sure.
If you are interested in this book, click on the picture at the top of this post. It will take you to the book on Amazon.com.
Here’s my swatch with the new color scheme added. The darker blue color definitely shows up better than the lighter blue against the teal color that I want for the main color. I have started knitting the romper in the darker blue and I think I’m going to really like the coordinated outfit that will result. This project is a bit challenging because I am knitting on size 0 and size 1 needles to get the right guage. Lots and lots of small stitches…
