Topic Tag: dirty

At the moment, the blades in my machine end up dirtying plastic I put through them. I've given them a bit of a clean, but since they're hardened steel, they rust, and I have to put a lubricant coating on to stop that, which also contaminates the plastic. How should I go about addressing this? I've coated the rest of the shredder with Zinc, but that coating isn't very scratch resistant, so it'd flake off very quickly if I used it on the blades.