I check the instructions on the bag or bolt for the batting. If it calls for up to 10", usually a 1/3 of that is good for tying. That is about the width of a hand my hand in the knuckle area. The other day, I was getting ready to baste a small whole cloth quilt for my dogs. I thought geez while I'm doing this I could be tying. Worked for me all I had to do was bind it. I was practicing but it worked for furbabies. I was basting the Sharon Shamberg technique with the 2 boards.