Can you use a Bench Grinder to Sharpen Kitchen Knives? (Advice)

A kitchen knife cannot stay sharp forever and it requires some sharpening to be done periodically to have a proper edge. But there are many techniques used for sharpening the knife.

Some techniques require professional sharpening skills and specific sharpening tools which give a high-quality finish and edge.

While some techniques involve simple tools but may not require professional skills and the final result is also very average.

In this article, we shall find out whether a bench grinder can be used for sharpening kitchen knives and whether it provides a better edge or not.

Can you use a Bench Grinder to Sharpen Kitchen Knives

Can you use a Bench Grinder to Sharpen Kitchen Knives?

You can use a bench grinder to sharpen kitchen knives, but it requires skill and practice to get a properly finished edge. The bench grinder has a rough abrasive wheel running at high speed which can only grind down the steel and doesn’t polish the edge. To get a polished edge, you have to replace the rough grit wheel with a smooth grit wheel. Also, you have to hold the knife at a proper angle to get a good edge. If you don’t follow a proper technique, a bench grinder may damage your knife.

Let us now find out how a kitchen knife must be sharpened to get a proper edge and understand why a bench grinder may not be the best choice.

Technique to Sharpen a Kitchen Knife

Traditionally, knives are sharpened using a whetstone. The knife is glided over the stone with slight pressure at a particular angle which removes metal from the rough edges and makes it sharp.

The quality of the edge and sharpness depends on the angle you are gliding the knife and how polished the edge becomes. Professional forgers have years of experience, and they know how to hold the knife at a proper angle and how well to polish the edge.

We shall look at the steps involved in sharpening a kitchen knife using whetstone and compare it with sharpening with a bench grinder.

Steps Involved in Sharpening a Knife

Sharpening a kitchen knife includes the following steps:

  • Grinding the edge to remove rough burrs
  • Polishing the edge to get a smooth sharp edge
  • Stropping to make the edge smoother
Grinding the Edge

When you want to sharpen a knife, the first step is to grind the edges using a set of rough grit whetstones.

When using a whetstone, you need to have stones with a different grit. It usually goes from rough grit to fine grit where the rough grit helps in grinding the steel on the edge and fine grit helps in polishing the edge.

So, take coarse or rough grit whetstones and apply some honing oil or water to ensure smooth gliding over the whetstone.

Usually, a single whetstone will have two sides where one side will be rough, and the other side will be smoother than the rough side.

Apply some honing oil or water over the rough edge and hold the knife at a 20-degree angle. This angle is very important to get a proper edge and it is quite easy to achieve the required sharpness.

Once you hold the knife at a proper angle, draw the knife from the base to the tip at a 20-degree angle. Repeat this step at least 20 times to get the required finish.

Now turn over the whetstone and do the same process 20 times. Likewise, complete the grinding process with all the rough grit whetstones.

Polishing the Edge

Polishing also involves the same process as grinding but it involves the use of smooth grit whetstones.

As you progress further with the whetstones, you can find that the surface grit is smooth, and it starts polishing the edge.

You can find the edge to become shiny and sharp and finally, you will have a properly shaped edge in your kitchen knife.

Stropping the Edge

Stropping involves drawing the blade against a strap of leather which helps in removing the leftover burrs in the edge and smoothen it further. This helps in getting more smoother finish to your kitchen knife and makes it easier to use the knife for fine cutting.

This is the proper technique to sharpen a kitchen knife or any other knife for that matter. Now let us look at the difference that occurs in grinding with a bench grinder.

How Sharpening with a Bench Grinder is Different from Sharpening with a Whetstone?

A bench grinder has a grinding wheel that is run by a high-speed motor. Similar to a whetstone, the grinding wheel is also available in different grits. But you have to dismantle and install the different wheels to get a smoother finish. This is quite tedious in a bench grinder, and it is traditionally not used like that.

Also, there is always the risk of chipping or damaging the edge if you don’t hold the knife at a proper angle. You must firmly hold the knife at a 20-degree angle against the wheel and gently glide it over the high-speed wheel to sharpen the edge.

If you don’t hold the knife at the proper angle or with firm hands, the wheel will damage the knife and you may not be able to use the knife again.

So, here are the differences between grinding with a bench grinder and grinding with a whetstone:

WhetstoneBench Grinder
Quality of SharpnessHighly quality sharp edge can be achievedHigh quality finish can be achieved but requires proper handling
Surface finish of Knife EdgeSuper smooth finish with polished edgesSmooth finish can be achieved but requires installation of different grit grinding wheels in the bench grinder machine.
Time taken to sharpenTakes hours to sharpen and to get proper edgeTakes only a few minutes to grind and polish
Skill requirementIf you can approximately hold the knife at proper angle, you can do it on your own without much practiceRequires professional skill to use the bench grinder. Also, it requires steady hands to avoid any damages
RiskThere aren’t many risks in sharpening with a whetstone since there are very less chances of damaging the edgeYou may risk the integrity of knife since the high speed wheel may damage the edge.

Conclusion

Bench grinders can be useful in an industry setup where you have to grind or polish a lot of items in bulk. But if you want to sharpen a kitchen knife for your personal use at home, you can make use of a whetstone to get the required finish. But if you aren’t too much concerned about the proper finish or high-quality edge, then you can simply do a few swipes in a bench grinder.