What Is Grain?
Fabric has a grain. What does this mean? Well, like many other things, such as hair, wood, fingernails, and even meat, there is a certain structure within a substance called a grain, and knowing how to use it can help you a lot. For instance, cutting meat perpendicular to the grain creates sharper blockier pieces instead of globby bits. You don’t usually brush UP your hair because there are little scales that grow DOWN your hair. And people may tell you that you should file your nails or sand a piece of wood in the same direction instead of back and forth because it’s more productive and less damaging.
Even meat has a grain!
Grain Lines In Fabric
A fabric grain is created by the fibers itself. In virtually all fabrics (and there are exceptions), fibers are woven perpendicular to each other, like a grid. There are vertical and horizontal lines. On most fabrics you can find a selvage: this is the finished edge of the fabric, where it cannot unravel, and can be identified by having a different texture, and sometimes different color. There may be words or letters printed here, and oftentimes little dots appear as well. The selvage is a very very important guide when it comes to knowing the grain of the fabric. The selvage is always vertical, or is the length of the fabric. Perpedicular to it are the horizontal fibers, and that is the width. The fabric cannot be wider than the selvage to selvage- that is the width that remains constant for that fabric. Fabrics come in many widths. However, the length is your yardage- when you order three yards of fabric, that’s three yards in fabric length, plus the however many inches in width that the fabric comes in.
The fibers that run the length of the fabric are called warp. The fibers that run the width and are perpendicular to the selvage is called the weft or filling. If you go diagonally on the fabric, that is the bias. A true or perfect bias is half way between the warp and the weft, or is at a 45 degree angle.
Why Do Grain Lines Matter?
Now, you may be asking yourself, why does any of this matter? It’s just a bunch of mumbo jumbo, I just want to cut my fabric, it looks the same in every direction. Hold your horses, even if it looks the same, it most certainly is not the same in every direction. For some fabrics that have obvious patterns or textures, if you lay your pattern pieces and cut in any way you wish then when you put it together, the patterns may not line up. If you’re making a pinstripe jacket, for example, you wouldn’t want your sleeve to have horizontal stripes and your jacket to have vertical ones. Unless it is supposed to be that way, but usually that isn’t the case, and you’d still have to think about that before cutting the fabric.
Cutting on the Grain Lines
On your storebought pattern pieces there are straight lines with arrows called grainlines. This should nearly always be placed perpendicular to the selvage when cutting fabric unless you have a specific reason to do otherwise. Here’s the meat and potatoes folks, if you do NOT do this you are going to risk giving yourself some major headaches later on. Some fabrics that have two way stretch, such as certain denims are best used if you make sure the stretch goes horizontally on the leg to make movement and fit more comfortable. Similarly, if you mix up your stretch direction and cut jacket pieces in varying grain lines, when you sew, some pieces may stretch and not line up when the corresponding piece does not stretch, making it difficult to match pieces correctly. Most storebought patterns will give you a guide, based on the width of your fabric, in which you can arrange your pieces so as to waste as little space/fabric as possible.
Utilizing the Bias Cut
And the bias cut? Oh the bias cut. On almost all fabrics, the bias cut stretches. It has the most give, and the most stretch. Try it on a non-stretch fabric- pull it vertically, horizontally, and then diagonally. The weave should stretch only on the diagonal, either slightly or quite a bit actually. While cutting ont he bias can mess you up if you’re trying to make a simple blouse or jacket, this can be very helpful for certain garments and is used a lot in haute couture to improve the garment fit and drape. It reduces drag lines and also makes a more comfortable fit, but since you’re cutting the piece diagonally, it tends to take up more space and thus more fabric. Some full length dresses need TWICE as much fabric than they would if they were cut lengthwise, equalling several yards needed in fabric, up to 6 or even 9.
There’s also a magical thing called bias tape. You can buy this at most sewing stores, and also make your own, and as the name implies, it is cut on the bias.
While I don’t expect everyone to mind their grain lines (even I cheat sometimes if it’s urgent), it helps a lot to know, especially if you are using a fabric with a more visual grain, such as stripes, or with a certain print or texture. So if you were anything like me, back when I would cut off the ugly selvage, and totally ignore the grain lines and just try to fit as many pattern pieces together like tetris blocks that I could, now you know how to use those things to your sewing and cosplaying advantage!