Professional Kitchen Knife Repair & Restoration UK

Knife Sharpening Explained.

What Actually Happens When a Knife Is Sharpened?

Knife sharpening sounds simple enough. A blunt knife goes in and a sharp knife comes out. But there is rather more to it

than that.

At Blade & Butler, we don't regard sharpening as simply putting an edge back onto a blade. Every knife arrives with its

own geometry, steel, profile, thickness, previous sharpening history and, quite often, a few surprises.

Two apparently identical chef's knives can require completely different approaches.

The purpose of sharpening is to create a clean, functional cutting edge while removing as little material as possible.

The job is not to make every knife look identical. It is to restore the knife so that its edge and geometry are

appropriate for the knife itself and the work it is intended to do.

How A Knife Becomes Blunt

A knife does not normally become blunt because the steel simply disappears. During use, the very edge of the blade can

roll, deform, chip or wear. Repeated sharpening can also gradually alter the geometry of the blade.

That narrow ‘V’ becomes a fat ‘U”.

When we sharpen a knife, we remove enough steel from the cutting edge to establish a fresh intersection of the two

bevels. On a double-bevel knife, material is removed from both sides. On a single-bevel knife, the geometry is different

and the sharpening process is carried out on one side only.

Why There Is No One 'Correct' Sharpening Method

Knife sharpening companies with less experience will boast that their way is the best.

However, there are many ways of sharpening knives and most can work when carried out correctly.

At Blade & Butler, every knife is assessed individually. Our knives are sharpened by hand on custom-made,

water-cooled aluminium oxide wheel sharpening stones. The final polishing, buffing or honing treatments can vary according to the steel, original

finish, geometry and condition of the blade.

We are also the only sharpening company to work to defined procedures and tolerances. Once the correct edge has been achieved, steel removal stops. We don’t want to waste your knife or our time.

The Importance Of Geometry

Sharpness is only part of the story. A knife with an extremely sharp edge can still perform poorly if the blade is too thick behind the edge. It may struggle to pass through food cleanly and can feel more like a wedge than a cutting tool.

This is why we look at blade taper, thickness behind the cutting edge, bevel width and profile as well as the immediate

edge. A knife should not simply be 'sharp'. It should be suitable for its intended job.

How We Check Sharpness

Every knife we return is hand checked and must pass our filmed Tomato Test before it leaves the workshop. The test is

designed to give us a practical, repeatable indication that the knife has a clean cutting edge.

We do not rely on naïve “sharper than new” ( How do they know how sharp your Global G2 was 20 years ago? ) nor do we need machines to tell us a knife is sharp. We don’t need machines.

Just like an elderly mechanic listening to an engine purr, after years doing the job, you just know.

When you choose Blade & Butler you get our 125 year knowledge for free.