I used to change the blade when it starts skipping because they are so expensive. I now buy a 45mm blade from Harbor Freight. They are called carpeting cutter replacement blades and you get 2 blades for $1.99. The cost makes it a lot easier to toss them quicker. I've never had one to be dull or cut funny right out of the package but you do need to wipe the oil off them before using. If you read the reviews for the blades most of them are quilters who like them.