Most of the “heavy machinery” in my shop has a smooth uncoated metal surface on it somewhere. From the ShopSmith tools to the 13″ Delta planer sitting in the corner, there are plenty of opportunities for rust to happen. Applying a coat of paste wax twice a year just doesn’t hit the top of my list very often. OK, so never.
If you look at the manual for most of these woodworking machines, they require a thin coat of well-applied paste wax on the active surfaces to keep them smooth, slippery, and above all, free from rust. It’s a pain in the rear, but wax will keep your tool surfaces in service for decades if you manage to keep the rust off them.
It’s funny — as a kid I used to watch my dad fussing over metal surfaces and wonder why he bought such cheap tools that they didn’t finish painting them. I even helped him out once by hitting the jigsaw baseplate with a can of red Krylon and wondered why the heck I had to spend the rest of the evening in my room. I didn’t know till adulthood that the smooth parts were actually the expensive bits. Live and learn. Paste wax is your friend.