When I pull fabric off the shelf, or out of the dryer, it’s pretty wrinkly and needs to be ironed before cutting. Sometimes it’s still wonky after ironing. The grain is slightly twisting one way or the other. Right here I have an easy decision to make. 1. I line up the fabric best I can and cut into it come what may. 2. I take an extra few minutes and square up the fabric before cutting any pieces off grain and ending up with a twisting shirt. (For me it’s going to depend on what I’m sewing; a drawstring pouch? I throw caution to the wind. A Liberty of London cotton shirt? I take the time to start it right)
Let me show you how to true up your fabric for those times when you need to.
Remove the selvedge to release the threads so they can straighten up if they want to. The tight selvedge can pull and hold threads off grain.
To remove the selvedge make a small snip parallel to the selvedge and rip down the lengthwise grain by pulling with your two hands. Remove both selvedges.
Press using a lot of steam (if your fabric can handle it). Take notice that the torn edge may roll under. Be sure to iron it flat. The threads may release their old ways and fall back in line; a straight line.
Give some quick tugs along the bias in both directions. And just don’t pull on opposite corners but tug on a 45 degree angle along other points of the edges too. Press again.
Great. The stripes are standing tall and my lengthwise grain is looking straight. Ah, wouldn’t ya’ know it? The cut across the bolt was shabbily done, How do fix that?
If you look closely you can see the weft threads (the threads that are woven across) and you can see where your lowest weft thread lies.
On the now torn edge (where the selvedge once was) make a little snip at about the same height as your lowest weft thread. You are making the snip to gain access to one, any one, of these weft threads.
Pick a thread and pull it toward you. Pull carefully and use your free hand to push the fabric away from your pulling.
The thread may break in this pulling. If it does (and it probably will) get a pin and dig the thread out from the cloth somewhere along your pull line. Somewhere it’s a little loose. Bring up the thread and begin pulling again.
By pulling a thread out of the fabric you are able to see the cross grain. The space left by the absent thread is now a clearly visible cutting line.
Cut on this line and you will have a trued piece of fabric for any sewing need and desire.