Ggtkuk

In order for knives to be useful, they need to be sharp. If I am sharpening one myself, how do I know when I am done?

What would be a simple easy test of whether a knife is sharp enough?

Try to slice a piece of paper. A good sharp knife makes a clean cut. A dull knife makes either a ragged cut, or worse, just pushes the paper to the side. I like this article: https://www.fieldandstream.com/articles/hunting/2014/08/paper-cut-testing-blade-sharpness#page-4 and YouTube is full of videos of people showing off their knives via this test.

The back of a fingernail can be a good rough indicator while you're sharpening - see if it "catches" when you apply very gentle pressure at ~45 degree angle. This can also be a good way to check if the edge still has any dull spots.

Slice a tomato with very little pressure. This is almost always when I notice a knife needs sharpening, and the difference is profound.

The best method in my opinion is one that must be learned, and involves moving your thumb across the blade, perpendicular to the blade not down it! It's very difficult to describe the feeling but if you do it on enough dull blades and sharp blades you will begin to be able to tell the difference.

One other thing I will do if im sharpening a knife for a friend or coworker to display how sharp it is is shave a couple hairs off the back of my hand. Lick your thumb, moisten the patch on the back of your hand and shave as you would with a straight razor. (You may want to wipe the knife clean after this.) Sounds weird but i do it because your average joe will know its extrememly sharp if you can shave with it and be careful with it.

One other test could be to attempt to very thinly slice a tomato, with and exceptionally sharp knife you should be able to get nearly paper thin slices with a light sawing motion.

You hold it edge up and then you let a silk scarf slowly float down over it. It should be cut neatly in half.