I cleaned out some drawers in my quilting room and found 4 packages of different size rotary blades that were probably close to 15 years old or more and never opened. They too were frozen together as the oil had dried. DH took them apart (he was a tool and die guy, so had the correct tools to not mar the blades) cleaned all the dried hardened oil off of them and then he put a coating of sewing machine oil on them. Good as new.