Originally Posted by amma
pillow case is where you sew the quilt sandwich right sides together leaving an opening so you can turn it out. You use this method instead of binding the outside of the quilt. Usually you would then top stitch around the edges of the quilt and hand sew the opening shut...
I am not sure what knife edge means? Maybe ironing something so the crease is really crisp and sharp?
Oh, Amma, I didn't know that about the pillow case term. Here it's called 'Bagging out'. I think your term sounds nicer.