There's a tool available from
www.ezquilt.com called "Easy Dresden" for the pointed blades - not for rounded ones. You cut a vee shaped wedge, flat across the top, then sew that flat seam, turn it inside out and end up with a point that doesn't have raw edges. So much easier than turning under the edges to applique. I haven't tried it, but wonder if the same technique could be used to make rounded blades.