I covered cleaning geared openers in a youtube video before, but I haven’t taken my own advice lately. I pulled out my spare US made Swing Away and realized I hadn’t cleaned it in a while. Cleaning a geared food tool may be the single aspect which throws people off. Many folks expect everything to be dishwasher safe, whereas can openers will certainly survive the trip, they need an extra bit of attention to have a long life.
Obviously the blades are NOT stainless steel, they will rust if you ignore it, but the rust isn’t the issue. A good scrub brush will get into the gears and creases to work out the bits of food and paper that may accumulate. And if the blade looks a little cruddy, steel wool or my favorite, the wire toothbrush now and then keeps it clean. After washing, dry it quick on a warm stove top and then add a drop of lubrication to any hinges or gears. When your done you can actually HEAR the gears make the clicking noise like the chain on your bike.
I keep a little spray bottle of mineral oil on the window sill for things like this, but I actually made a girlie squeal the other day when I found a lubricating pen at the hardware store checkout. Now it lives on the window sill.