I cleaned the sawblade by using a scraper for the grime and surface rust. Then using Naval Jelly and a stiff nylon bristle brush removed the rust. After that it was coated with WD-40 and sanded starting with 220 and progressing through 0000 steel wool.
The medallions and screws were cleaned with Barkeepers Friend and polished.
Im pretty happy on how it turned out.
-- “There is nothing like looking, if you want to find something. You certainly usually find something, if you look, but it is not always quite the something you were after.” ~ JRR Tolkien