I do that a lot, especially with throw-sized quilts. I find binding cut across the grain stretches just enough so you don't have to cut it all on the bias. I love the way it looks. I use a smaller plate, though - lunch or salad size.

I've made a couple of bed quilts that went to the floor--I used rounded corners at the foot of the bed, and square corners at the top. I used straight of grain binding and had no problem, since the curve was gentle.

I have done the same thing but instead of rounding, I just cut off the corner sort of like half of a HST. You can take off as big or as small a chunk as you want. You do end up with eight 45 degree angles in the binding but they are no harder than 90 degree angles. Plus you can use straight of grain binding.

When I was still hand sewing on the back I use to round all my corners. I bought a rounding tool from Annie's Attic and used that. I found I had to pull WOF binding strips taunt around the corners when sewing onto the front of the quilt with machine. I was very happy with end result. I never tried to machine sew on the binding on then.

Now I make quilts for kids 45" x 60" and miter the corners and sew with machine.

[QUOTE=Prism99;7960069]You probably want to use bias binding for this. [QUOTE]

If you wanted to use straight grain binding, I think it would work because that is such a large curve. I usually stretch the binding just a bit as I sew it on, but on these curves I would not stretch it at all. Then it wold lie flat after it is turned.

I think bias binding would be a good choice on quilts.