I'd like to add: Changing your rotary cutter blade when you have to cut "twice" to make the cut. I tried to extend the life of my last blade and when I finally put in a new one it literally "cut like butter". So much easier than pushing hard to cut fabric and not taking it easy on my newly repaired rotator cuff. Not smart. So, my advice would be that when it becomes hard to cut - change the blade, you'll be glad you did.