Let me try to explain it better!! LOL
I'm trimming the selvage of the fabric. But when I square it up with the end of the fabric which I've already squared up, the selvage edge gets wider and wider as I move along the yardage.
Why would it do this? That's just means that by the time I trim the selvage that has been squared, the straight of the grain is going to be off.
Did this make sense?