Can Opener and Knife Sharpener Combos: Honest Verdict

The sharpening slot built into a can opener is the least capable sharpener sold today. It still earns a place in some kitchens. It rides on an appliance you already own, and it asks nothing of you but a slot and a few passes of the blade.

A can opener with a knife sharpener slot sounds like a two for one deal. In practice it is two different jobs bolted onto one motor. Only one of them was ever the point.

What a can opener and knife sharpener combo actually is

Most current combo units come from Hamilton Beach, the dominant name in this category. Models like the SmoothTouch line open cans from the side instead of the lid. They also add a removable bottle opener attachment and tuck a small sharpening wheel into a slot on the back of the housing.

You flip the unit around, drag the knife through the slot a few times, and flip it back. Several other Hamilton Beach models carry the same slot, along with commercial versions sold for restaurant kitchens. This is a whole product class, not one odd feature on a single model.

How the sharpening slot actually works

The wheel inside the slot is a small abrasive disc set at a fixed angle. That angle is built to match a can opener’s own cutting wheel. That wheel is thin, soft steel ground close to sixty degrees so it can survive prying against a metal lid without folding.

A kitchen knife wants a much narrower edge, usually somewhere near fifteen to twenty degrees per side. The slot cannot tell the difference between the two jobs.

It grinds every blade the same way regardless of the angle that knife actually needs. That same fixed angle also explains why the wheel wears a blade unevenly over time. A dedicated sharpener uses guides built only for cutlery, never for opener steel.

The honest verdict on a can opener and knife sharpener combo

For a beater knife you keep around for cardboard boxes and stubborn packaging, that crude edge is plenty. For anything you actually cook with, the slot is a last resort tier tool at best.

It gets an edge back to cuts faster than it gets an edge back to shaves. That is the ceiling.

Owners who expect whetstone results from a can opener are usually disappointed. The two tools were never built to the same standard.

The vintage wall mount angle worth knowing

The idea did not start with electric appliances. Swing-A-Way built its business on a 1938 wall mount can opener. In 1945 it added a gear driven cutting wheel that made cranking smoother.

The handheld Model 407 launched in 1954. It went on to sell around two hundred million units over the next five decades, and it earned a Good Housekeeping Seal and a spot on NASA’s Skylab.

Kitchens of that era often paired a wall mount can opener with a small companion wall sharpener nearby. Each tool did one narrow job.

Swing-A-Way stayed family run for decades, then changed hands in 2005 and moved production overseas soon after. That older, blunt sharpening idea is exactly what survives inside today’s combo appliances.

What to buy instead if you actually want a sharp knife

If sharpening matters to you, skip the slot and buy a real sharpener built for knives instead. It costs next to nothing next to the price of the appliance itself.

More options exist built specifically for this job. We cover manual sharpeners built for the job in more depth separately.

Where people go wrong with a combo can opener sharpener

• Running a favorite kitchen knife through the slot expecting whetstone results.
• Sharpening at the slot’s fixed angle, then touching up freehand at a different angle, which confuses the bevel.
• Buying a combo appliance specifically for the sharpener feature. A separate can opener plus a real sharpener usually serves better and costs about the same.
• Assuming every current model includes the sharpener slot, since several can openers on the market skip the feature entirely.

When the combo is honestly fine

Some kitchens do not need any of this. If you open a few cans a month and never touch a whetstone, the slot on the back of your opener still helps. It works as a fine safety net for a dull paring knife.

Buy a dedicated sharpener only if edge quality actually matters to you, because the combo slot will not close that gap. For anyone ready to stop compromising, our full home sharpener guide covers the options worth owning.

Frequently asked questions

Can a can opener really sharpen a knife?

It can restore a working edge on a dull blade, not a fine one. The wheel is built to match a can opener’s own crude angle, not a kitchen knife’s edge.

Do all combo can openers have a knife sharpener?

No. Most standard can openers skip it entirely. The slot shows up mainly on Hamilton Beach style models and a handful of competitors that build it in as an extra feature.

Will the sharpening slot ruin my knife?

It will not destroy the blade, but it grinds at one fixed angle every time. Repeated passes remove more metal than the job needs and can leave an uneven bevel. Save it for knives that are already inexpensive and replaceable.

What is a good cheap alternative to the built in sharpener?

A manual pull through sharpener like the AccuSharp 001C costs about the same as a takeout lunch. It actually targets a kitchen edge angle instead of a can opener angle.

Are vintage Swing-A-Way openers worth using for their sharpener?

Vintage wall mount units are collectible and often better built than new imports, but their companion sharpeners were designed for the same crude job. Treat them as nostalgia, not precision tools.

Is it worth buying a combo can opener just for the sharpener feature?

No. Buy the can opener wanted on its own merits, then add a real sharpener separately if edge quality matters.

Browse our other workshop gear guides for more sharpening breakdowns beyond this one appliance.