I wonder if anyone can help: I have been given a centrifuge, albeit an old one. It is quite rusty but that comes off quite well with wirewool. However, the next day the rust starts to come back. Can anyone recommend something to treat the metal with which will stop it re-rusting but also not be unpleasent or dangerous to eat when I enjoy the honey. I am imagining WD40 for the outside, but inside I just do not know. Olive oil or sunflower oil, but they might go off over time... Any ideas?