Originally Posted by PaperPrincess
I do know that you are supposed to take a larger seam allowance on backing seams and press them open. If the quilt is going to be long armed, it will lay better if the backing seams are horizontal or diagonal.
Horizontal or diagonal seams on your backing REALLY helps on a long-arm as a vertical seam builds up on the rollers creating an uneven roll that leaves the sides floppy and creates a tight lump that has to be quilted over on each pass - lots of needle deflection.
I press my seams to the dark unless there will be more than 4 pieces of material at the junction, then I will press open to eliminate the bulk (needle deflection when quilting really messes up the quilting). Like pinwheels...the HSTs will be pressed to the dark, all other seams will be pressed open.
Mostly how you press your seams is personal preference for you and for your quilter! :thumbup: