Short answer is yes: paper, and much more so cardboard, are high impact items to a knife's edge. This is because paper items are abrasive to a point that they do a good job of making a blade edge dull. This is at least partially due to most paper being made from trees; and tree fibers are tough.
Never cut on glass, ceramic or countertops. Those surfaces are harder than a knife's edge and will quickly dull the blade. It's what you cut on that dulls knives, not what you're cutting.
Avoid using your knife on surfaces made of glass, granite, marble, or ceramic. These materials are much harder than steel and will weaken your knife's edge. Even a quick slice on a ceramic dinner plate, a marble cheese board, or a granite countertop can dull your knife.
Cardboard boxes are readily available and inexpensive material that can help you sharpen your knives quickly and easily. The method: Cardboard fibres act much like those of honing steel and help realign the blade's edge. Grind along both sides simultaneously as you bring them towards each other in a sawing motion.
A knife will get dull if not used for its intended purpose. This is obvious. According to a silversmith, a folding knife can get dull as a result of dirt and dust in your pocket. Wiping the dust and dirt off the blade results in the debris rubbing against the edge of the blade thus wearing at the edge and make it dull.
You should only cut meat, chop vegetables, slice bread or sausages on a kitchen board. Countertops are usually made of hard material and will quickly make dull your blades. Wooden or plastic cutting boards have minimal impact on the sharpness of the edge.
LPT: Cutting through aluminium foil will sharpen your knives/scissors. : r/LifeProTips.
Short answer is yes: paper, and much more so cardboard, are high impact items to a knife's edge. This is because paper items are abrasive to a point that they do a good job of making a blade edge dull. This is at least partially due to most paper being made from trees; and tree fibers are tough.
It's crucial not to sharpen your knife too frequently or apply excessive pressure, as this can cause the blade to become thin and brittle.
Paper and cardboard are full of abrasives and are not really soft. You don't feel the abrasives with your fingers but the knife edge encounters them when cutting. Some people use the dense cardboard back of a notebook as a strop to finish sharpening their knives.
Repeatedly snagging and releasing the knife puts you at risk of accidental injury. Even worse, cutting foam quickly dulls knife blades, so you'll need a knife that has blades that are easily replaced.
The magnets themselves don't dull them; they're not nearly strong enough to deform a blade. But it is possible to damage your knives on those racks.
Electric knife sharpeners
You can use an electric sharpener, too. The process is much the same, with the added benefit of speed. These products have both honing and sharpening slots. Dragging a knife through the slots accomplishes the same task.
In addition to their cutting ability, serrated knives are also known for their durability. Because the teeth on the blade are not as fine as those on a straight-edged knife, they are less likely to dull quickly. This means that serrated knives often go longer between sharpenings than other knives in your kitchen.
Sharpening Angle Too High
In practice, an angle that is only slightly too steep will not dull the edge. Only very high angles will create edges that feel dull. Sharpening at a slightly higher angle will actually speed up sharpening, but at the expense of maximum sharpness.
While some stones – like those made of diamond or ceramic – can be used dry, they still usually benefit from a little water. Soaking the whetstone is important because it helps protect the stone from damage and wear. Sharpening your knives with a dry stone won't hurt the knife, but it will damage the stone over time.
How to use a Manual Knife Sharpener: Place the knife against the coarse side of the sharpener and swipe it across the surface around ten times. This initial step sets the foundation for a sharp edge. Afterwards, switch to the fine side of the sharpener and repeat the swiping motion ten times.
The answer is yes. We won't shame you for it, but we do have to take off a lot more steel than a normal sharpening, so please stop using pull-through sharpeners. According to you, our customers, they are repeatedly the cause of the most damaged blades we see.
Burning cardboard can release dangerous chemicals such as dioxins and furans, especially if the cardboard has been printed with colored ink. These chemicals are not only harmful to your health but also contribute to air pollution, damaging the environment.
Cardboard is internally very abrasive. It's like cutting high grit sandpaper. Like the other very detailed post said, there can be better angles and steels than others, but a high end knife with expensive steel isn't the right tool for the job in the first place IMO.
They Dull Your Knives
It's simply too hard a material for most knives to withstand. As your knife cuts through your carrots, onions, or any other food, the blade will knock against the glass, which will dull the sharp edge you've worked so hard to maintain.
Rough surfaces such as a nail file, sandpaper or an emery board can be used to sharpen a knife, running the blade along the entire length of the file or surface.
Option #4: Cut Aluminum Foil
This technique is similar to cutting sandpaper, only you use aluminum foil. Again, this will hone slightly dull scissors, but it won't sharpen scissors with very dull or damaged blades.
It's best to avoid wrapping food in aluminum foil for extended storage, particularly for acidic or salted foods. Prolonged contact with moisture, acids, or salts an cause the foil to degrade, allowing aluminum to leach into the food. This can affect the food's taste and raise potential health concerns over time.