How does a smooth edge can opener work differently from standard?
A standard can opener's cutting wheel presses down on the lid from the top and rotates through the metal, cutting the lid disc out of the can top. The cut edge is a raw metal edge. A smooth-edge can opener positions its cutting wheel on the outer side of the can's top rim (the seam where the lid is crimped to the can body) rather than on top of the lid. The wheel cuts through the seam from the side, releasing the lid as a flat disc. Because the cut is through the seam rather than through the lid metal, the released disc has the factory-folded edge on one side (smooth) and the cut side (which cuts through the thinner seam material rather than the thicker lid metal) that results in a smoother edge than top-cutting. The can body's rim is similarly smooth after a seam cut. The technique difference: the smooth-edge opener is turned so the cutting wheel is on the side of the can rather than on top, which takes one or two practice attempts to get right.
Which smooth edge can opener is easiest to use?
The Kuhn Rikon Auto Safety LidLifter is the easiest smooth-edge can opener to use because the auto-advance mechanism advances the opener around the can without the user needing to maintain constant pressure on the cutting wheel. The opener is started at the can's edge, the mechanism auto-advances around the circumference with minimal hand cranking force, and the built-in lid-lifting arm holds the lid above the can after cutting so it can be discarded without touching. EZ-DUZ-IT is the second easiest for straightforward operation: the side-cut positioning takes one practice session to learn, but the operation is then consistent. OXO Soft Works adds ergonomic soft-grip handles that reduce hand effort during the cutting pass around the can. For users new to smooth-edge openers, the biggest learning point is initial positioning: the opener must be started at the outer seam rather than the top lid, which is intuitive after the first can.
Can smooth edge can openers open all types of cans?
Smooth-edge side-cut can openers work on standard cylindrical cans with a crimped rim seam where the lid meets the can body. This covers the vast majority of canned goods: vegetables, beans, soups, tomatoes, fish and most other pantry staples. They do not work on pull-tab cans (the lid is already designed to be opened without a tool), on cans with deeply recessed rims where the seam is inaccessible, or on cans where the lid is attached to the can body by a method other than a standard crimp seam. Most canned goods in the standard 14-ounce to 28-ounce format used in home cooking have accessible crimp seams. Very small cans (sardine-style flat cans) may have seams too shallow or narrow for a smooth-edge opener's wheel to grip; a standard top-cutting opener is more reliable for unusual can shapes and sizes.
