Knife Advice: Pull-Through Sharpeners

We see it all the time, but you won't until it’s too late

Written by Alena J

 

Kitchen knife damaged by a pull through sharpener and note from customer

Honing steels are in and pull through sharpeners are out.


Over and over again we get these funny little notes in our dropbox saying.


“Can you fix it?”

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. The story usually goes,


“It used to work so well then one day I was using it and on a single pull, the knife went - dink dink dink dink - thunk thunk.”

Here is our hypothesis; the first few times you use a pull-through sharpener, it seems to work because its removing the burr (the piece of metal that folds over when you use a blade, often times in opposing directions). The minute it’s actually removing any steel from the blade or attempting to make a new edge, it runs into several problems. The angle is never exactly the same and its not removing enough steel to create a single clean bevel. Similarly the pressure is uneven as the blade pulls through, removing uneven amounts of steel along the length of the blade. One day, one pull, and the brittle edge gives way.


Shun knife damaged by a pull-through sharpener
Shun knife damaged by a pull through sharpener (before)

The more it’s used, the more it weakens the steel in different places along the blade until on a single pull the weaker points break leaving many chips along the straight edges and larger chunks out where the blade starts to curve.


Additionally, because of the way knives are made, as steel is removed, the blade becomes thicker as it comes towards the spine. If a knife has a bolster, there is usually a 1/16th -1/4th inch of tapered steel as it approaches the back end of it. No pull-through, no matter how expensive, can maintain a blade’s shape.


If you're just looking for the best maintenance tool between sharpenings, a honing steel is easier to learn than sharpening. It still requires a little practice, but as long as you understand the intention is to bend the burr back straight and not actually remove any steel. So go gently and follow the angle.

Shun knife sharpened and repaired by Moleta
Shun knife sharpened and repaired at Moleta (after)

If you have a blade that's already been damaged by a pull-through, you can bring it to us and together we will pretend the dog chewed on it and you’ll take it home like nothing happened. Except, please do tell your family you had your knives professionally sharpened because if you thought your pull-through sharpener was doing a great job, you and the dog are about to have your minds blown.

 



Alena has been sharpening over a decade professionally. From farm to law firm, she found the perfect balance of power tools, art, and analytics in Moleta. She loves to garden, cook, craft and still gets excited for people to try their blades for the first time after she gets done with them.