A guide with video to take the mystery out of how to sew stretch fabric, including different types of knits
Hey y’all, welcome to sewing with knits month on the blog! This month I’m going to be covering tips and techniques for successful knit fabric sewing, and that starts with knowing your stretch fabrics. Because the more you know, the more likely you won’t curse your machine and give up on sewing stretchy fabrics forever after you try it.
So today I’ve got a video showing different types of knits, how they’re made, and how they behave. If the video below won’t load for some reason, you can also watch it here.
How Stretch Fabrics are Made
I happen to be a knitter as well as a sewist, so part of what I’m going to talk about is related to how the stitches are formed, because that helps explain the differences in the fabric. And by the way, if you want to see knit fabrics in motion, you should check out the video I’ve got in this post.
Knit fabrics are made of a combination of knit and purl stitches. The basic difference between those is whether the yarn is carried from stitch to stitch on the right or wrong side of the fabric. For knit stitches the yarn is carried on the back side. With purl stitches the yarn is carried on the front side.
In the picture below, you can see the horizontal yarn carried on the wrong side of the fabric. This fabric is formed by knit stitches on the right side and purl stitches on the wrong side.
This method of knitting the right side and purling the wrong side is how jersey knit is formed. The picture above is a sweater knit, but if you look really closely, you can see the same stitch pattern in the jersey knit below.
Because the thread is always carried on the wrong side of the fabric, jersey knits are not the stretchiest type of knits. Some, like the one pictured above, have spandex in them to improve stretch. Others, like sweatshirt fleece, barely stretch at all.
Jersey knit often curls toward the right side perpendicular to the selvedge and toward the wrong side parallel to the selvedge. This is due to the knit right side/purled wrong side construction. You can see how the fabric in my picture is curling along the cut edge.
Types of Jersey Fabric
In the picture above, the jersey knit is yarn dyed gray. Most jersey knits with a print on them are printed on the right side, much as quilting cotton is printed. Occasionally you will find yarn dyed print jersey, which has the print on both the right and wrong sides.
Sweatshirt fleece is another type of jersey knit, again knitted on the right side and purled on the wrong side. Then the wrong side of the fabric is brushed. Brushing creates that fuzzy look and feel that also makes the fabric warmer as it traps more air.
One more type of jersey is burnout jersey. This is made with yarn/thread that is a combination of cotton and synthetic fibers, usually rayon. It’s knitted/purled/printed like a regular jersey print.
But then after printing, a chemical is applied to the fabric that “burns” the cotton fibers off, leaving the synthetic fibers behind. The resulting fabric has see-through patches that you can see more clearly when the fabric is held up to the light.
What is Interlock Fabric?
Interlock knit is a type of double knit fabric. Without going into super technical details, it’s kind of like two pieces of jersey knit back to back with the same thread.
Because of this, it is stretchier than jersey. Interlock also looks the same on the front and back side, as the yarn is carried in the middle between the two knit sides. This also means interlock is typically a little thicker than jersey, and that it doesn’t curl. I recommend interlock fabric to people who have never worked with stretch fabrics before. It’s stable, usually has good stretch and recovery, and is generally the easiest knit to work with. Be careful though if you need four way stretch fabric, as some interlock fabrics don’t have much vertical stretch.
Ponte (pon-tee) or ponte de roma is a type of interlock knit, made with a blend of synthetic fibers.
Rib knit alternates knit and purl stitches on the same side of the fabric, then on the other side the knit stitches get purled and the purl stitches are knitted. So for example a knit pattern for ribbing might read knit two, purl two, repeat on the right side and purl two, knit two on the wrong side. This forms the vertical ridges you can see on the fabric above. Because the yarn has to be switched from front to back so often, rib knit is also very stretchy. Also because of the even distribution of knit and purl stitches on the front and back side, rib knit typically looks the same on both sides and does not curl. Rib knit is great for collars and necklines, because it stretches a lot and because it adds stability to jersey knits in those areas.
Types of Knit Fabrics – A Cheat Sheet
And finally, here’s a great cheat sheet on the types of knit fabrics. This covers the most common types of stretch fabrics you’ll find in stores. If you’re an absolute beginner to sewing with knits, note that I recommend interlock as a great starter fabric.
Remember that this chart refers to the construction of the knit, not the fiber. Fiber is what the yarn or thread is made of, like cotton, spandex, polyester, rayon, bamboo, etc. The same fabric constructed in different fibers will behave slightly differently. For example, you might have a cotton jersey or a polyester jersey. The cotton jersey will likely be softer and lighter and more breathable than the polyester jersey. The polyester jersey will likely have more drape than the cotton jersey. A cotton/poly blend jersey might have characteristics of both.
Want to read more about sewing with knits? See these posts: