bkay, as you know I am not a quilter, but from my understanding the lengthwise (vertical) grain is more stable. In other words the crosswise (horizontal) grain has a little bit of stretch, but not much on a woven fabric. My thinking is that on a small quilt, is that it should not matter. There could be a possibility of the material sagging a bit if it is to be hung, but for lap quilt or such, I doubt that it would be much of a problem. My first link that confirmed that the cross grain had a little more stretch was
https://www.thesprucecrafts.com/fabr...uilter-2821312 It show taking a square and stretch different directions. Here is another page
https://superlabelstore.com/blog/quilt-backing-fabrics/ and about half way down the page it states
For instance, the crosswise grain is pieced into another crosswise grain to enable extra stretching. On the other hand, the lengthwise grain is sewn to another lengthwise grain for less stretching capabilities.
Depending on the size of your quilting project, the seams for piecing your backing run either vertically or horizontally.
Janey - Neat people never make the exciting discoveries I do.
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