Can someone explain this to me please...

I read somewhere that the only time you need to cut binding on the bias is when you are going to be binding curves. Otherwise, you can straight cut the fabric width wise.

I only cut on the bias when I do a scallop edge,, otherwise on straight of grain.

I feel the bias bindings a tougher than the ones cut on the grain. They have more give, I think. IMHO

I've been told that bindings cut on the bias last longer.

That is what I believe also. When binding is on the bias, you will be able to gently stretch it and shape it around the curves.
There is less 'give' in straight binding.

But straight grain binding is just fine for straight quilts. It has enough strength because it is double folded. IMHO.

Here's a blog post that explains the differences between bias and straight of grain binding:
http://www.jaybirdquilts.com/2011/01...cs-part-1.html

and here's part 2 where she shows how to make bias binding:
http://www.jaybirdquilts.com/2011/02...rt-2-bias.html

I am going to try making my next quilt with rounded corners and use bias binding. I don't really like mitering corners.

Binding cut on the bias is more flexible and therefore it's easier to make it look nice when you fold it over and stitch it down. It's also easier (for me at least) to make nicer mitered corners with bias binding.

According to Barbara Brackman, reknown quilt historian, bias binding was rarely, if ever, seen on quilts prior to the scalloped-edge quilts of the 1920-1930s.

I prefer the look, feel, handling, and strength of double fold (aka French fold) binding with mitered, hand-turned, handsewn corners.

But, as you can see, it's a purely personal preference.

Jan in VA (quilting nearly 30 years.)

thats what I do :thumbup: :D