Paper wheel knife sharpeners are rarely used but effective in the right hands
Paper wheel knife sharpeners are one of the more esoteric types of knife sharpener on the market. They are rarely used, but that doesn’t mean they are no good. In fact some people with significant experience in sharpening knives swear by them, and some will even say that you will get a better edge with a paper wheel knife sharpener than any other sharpener
So let’s look at exactly what paper wheel knife sharpeners are and how they work.
The principal of sharpening a knife is relatively straightforward. You apply a form of grit, or abrasive, to the edge of the knife to take metal off the edge to make a fine edge, and if needs be you hone that edge to produce a final result.
All knife sharpeners work the same way, including paper wheel knife sharpeners. They are different versions of the one principal, namely that to sharpen a knife some metal needs to be removed from the edge of the blade.
(Note that I said knife sharpeners work the same way. This does not apply to knife honing steels, which are sometimes mistakenly referred to as knife sharpeners. This is incorrect, they do not sharpen a knife but they hone the edge of a knife.)
Steel is removed from the edge of the blade when it is rubbed on an abrasive. Whether the abrasive is contained in a sharpening stone, grinding wheel, sanding belt or commercial knife sharpening tool, the object is to remove small amounts of metal from the blade.
A paper wheel knife sharpener is exactly the same. It is just a different way of applying an abrasive to your knife to remove metal.
here are of course many ways will apply an abrasive to the edge of a knife. Either the knife needs to be drawn across the surface of the abrasive or the abrasive needs to be taken across the surface of the knife edge.
Both of these methods are used in knife sharpeners. For example in many simple knife sharpeners the operator draws the knife across the abrasive contained in the sharpener, which is stationary. In others the knife is held against a rotating abrasive.
One common rotating abrasive is a grinding stone fitted onto a grinding machine. A common grinding machine that has a wheel with the appropriate grit will be perfectly adequate for sharpening a knife if the user has some experience.
A paper wheel knife sharpener works in exactly the same way. It also requires a standard bench grinder, and the wheel is attached to the grinder exactly as a normal grinding wheel is. It’s important that the grinder run at speed, commonly above 3000 rpm.
So what’s the difference between a paper wheel knife sharpener and a simple grinding wheel? The difference is in the abrasive.
A paper wheel is simply compressed paper with an appropriate grit, commonly silicon carbide, applied to the surface of the wheel. In other respects you use it pretty much exactly like you would use a normal grinding wheel.
However unlike with a normal grinder wax is applied to the surface of the paper wheel. The purpose of the wax is twofold, to help protect the grit and also to help reduce any heat that may be produced by the sharpening process.
Unlike many commercial knife sharpeners however it’s up to the operator to hold the knife at the correct angle. This is one of the great problems associated with many knife sharpeners, namely that the operator must choose the angle at which to hold the knife and then maintain that angled throughout the sharpening process.
For instance you can get a very good edge using a simple stone, however many users find it difficult as they are unable to hold the correct angle. The same applies to paper knife sharpeners, and you will need to practice before you get it right.
A few tips are useful. Make sure you have the edge facing with the direction of rotation of the wheel rather than against the direction of rotation. If it is held against the direction of rotation you run the risk of the edge digging in, at best damaging the wheel and at worst having the knife fly back into your hand causing injury.
Practice first with the motor off, holding the edge of the knife away from the direction of rotation and, holding your chosen angle, draw the knife backwards and forwards practising.
How do you choose the angle? There’s not much point giving you a figure because it’s very difficult to determine exactly what angle a knife is held on. However you should be able to look at the knife and see at what point the very edge of the blade is contacting the wheel.
If you’ve done it correctly you will have a slight burr on the edge of your knife. There are a number of ways of removing the burr including paper buffing wheels or a honing steel, or even a strop.
Note that the grit will eventually wear, even with use of the wax, but it’s perfectly possible to replace the grit on the wheel, it’s not necessary to buy a new one
Here’s a video giving a little more background on using a paper wheel knife sharpener.