Finally understand Rockwell hardness to keep up with the next best scissors for groomers discussion!

Endlich den Härtegrad nach Rockwell verstehen, um in der nächsten Diskussion über das Thema "beste Scheren für Groomer" Schritt zu halten!
Many groomers argue about what blade hardness the optimal pair of scissors should have. Some prefer softer steel - others prefer "ultra hard" blades made of Japanese steel.

But between us:
Most people have no idea and just want to have a say - without saying anything.

And you? Are you still looking through that? If not, you've come to the right place.

Here I will tell you:
  • What Rockwell hardness stands for and what the degree of hardness of scissors actually is.
  • What Rockwell hardness says about your scissors - and what it doesn't
  • How to find the right scissors for you based on Rockwell hardness

Are you ready to decide the next discussion about the different degrees of hardness for yourself? Then let's get started here together...



HRC: Rockwell hardness - what is it?
Simply put: HRC is the unit of measurement that G-POINT uses to check and classify the blade hardness of the scissors.

Just like the degree Celsius measures the temperature (I'm currently writing at around 20°C in my office when the sun is shining) or like the meter defines the distance from one place to another (my office is 6KM away from my home), the HRC gives the Hardness of the knife blade.

HRC stands for:

  • Hardness value of the blade = How hard is the blade steel used?
  • R ockwell = The measuring method named after the inventor Stanley Rockwell (but more from me later)
  • C one = The scale on which the value moves (Cone stands for diamond cone, with which the measuring procedure is carried out)


This is how you can understand it:

The scissors from Schnittscharf have a hardness of 56-58 Rockwell (approx. 57 HRC).
Or like this: G-POINT scissors, on the other hand, have a Rockwell degree of 62-64 HRC (approx. 63 HRC).
But also like this: Inferior steel is comparatively very soft and only has around 50-52 Rockwell and is therefore cheaper.

But what does the hardness of a blade say about scissors?
Do high-quality scissors have to have a high Rockwell grade? No - unfortunately it's not that simple.

The hardness of the blade does not tell you whether your scissors are of high quality, but rather what purpose you can best use them for.

An example:

  • A simple pair of scissors has a wide blade and soft steel so that the blade does not break immediately when it hits impurities in the fur, but remains "elastic".
  • However, high-quality scissors usually have a higher blade hardness, which means less wear and tear when cutting. This means the scissors stay sharp longer.

But before I tell you what the Rockwell degree of hardness reveals exactly about your scissors, the two of us will take a short, crisp trip to the workshop and take a close look at the Rockwell knife process.

G POINT
How does the Rockwell hardness test work? SIMPLE and SHORT explained

How to do it:

A rounded diamond cone with a 120° angle is pressed twice into the blade steel.

First the cone penetrates with a force of 98.07 Newtons - this is the so-called pre-force. The force is then increased to 1372.93 Newtons and the cone penetrates further - this is now the so-called main force. This pressure is held for a few seconds and then the main force is removed.

What remains is the preliminary force of 98 Newtons and the remaining penetration depth (e). Finally, the degree of hardness is determined using the following formula:

HRC = (0.2 - e)500 i.e.: [(0.2 minus permanent penetration depth) times 500]

By the way... Only steel can be tested this way - but not ceramic blades. Nevertheless, you sometimes see that the hardness of ceramic scissors is stated with an HRC value. That's not entirely true - but in my opinion it's still justifiable.

An example:
The Kizuna blade is a ceramic blade and is significantly harder than Damascus steel. In order to have an approximate comparison, an estimated HRC value is usually given - in this case ±80 HRC of a Kyocera ceramic blade.

But back to our scissors.
Let's move on and examine the most important question:

What does the degree of hardness tell you about your scissors?

How do you recognize a good, high-quality piece of furniture?
Mostly because of the material, right?

Here's an example:
A chest of drawers in the bedroom is robust, stable and high-quality if it is made of real wood - for example German oak.
A cheap sideboard in a student apartment, on the other hand, is soft and "brittle" if it is made from pressed chipboard glued together.

But:
Real wood doesn't always have to be hard.
A children's bed can be high quality and robust - but also soft, for example if it is made of soft cherry wood so that it doesn't hurt the children if they hit their heads.

It's the same with scissors...

The degree of hardness only gives you limited information about the quality of your scissors.
But you can use the following degree of hardness as a guide:

High-quality scissors usually have a blade hardness of at least ±60 HRC.
For all other scissors that have a lower hardness, you should find out exactly what steel it is, how the scissors were processed, etc.

But there are also 3 important pieces of information that the Rockwell hardness level reveals about your scissors:

  • Whether your scissors have hard or soft steel
  • What is the edge retention - how long does the cutting edge stay sharp?
  • How well can you sharpen it if the blade has become dull?

Let's now take a closer look at this together:

1.Hard steel and soft steel - differences?

50HRC. That's about how far down the Rockwell scale goes.

The lowest value for scissors starts at around 52 (for really bad steel even 50 HRC - but that's rare).

The highest value is 67 HRC - depending on the type of grinding and different hardening processes, it can even rise to 71 HRC in individual cases.

Here is an overview of the Rockwell hardness levels:

50 - 52 HRC = usually "cheap scissors" for 10-20 € in the Aisashop
You should stay away from such scissors.
They are usually mass-produced from cheap steel, rust more quickly and are poorly made.

But the biggest disadvantage is:

The steel is so soft that over the course of the day you will notice how quickly the cutting edge wears down. If you cut a Pomeranian in the morning and then cut a Poodle in the evening, you will notice that your scissors no longer cut through the fur so smoothly.

53 - 54 HRC = soft steel, flexible blades
particularly common with knives or solid “entry-level” scissors
The better knife steel starts from 53 Rockwell.

These scissors in the low price segment (€30 - €50) often have around 53 - 54 Rockwell and are more suitable for home use.

Why?

Because the cutting edges are flexible and forgive a lot of mistakes when cutting, as the cutting edge is usually ground at a wide angle and does not break if someone handles it clumsily.

You notice:

The hardness of the blade steel says more about the purpose than the quality of a pair of scissors.

55 - 56 HRC = typical blade hardness of entry-level scissors
High-quality blade steel (X50CrMoV15) is used here, which most of us know from the knives from Solingen (e.g. Zwilling, Felix, WMF).
The highest quality knives in the world are forged in Solingen and usually have a blade hardness of 55-56 HRC.

The "Solingen blade steel" X50CrMoV15 is used as a basis and some manufacturers harden the knives using additional hardening processes (more on this later).

These scissors are still flexible and because the steel is soft, you can easily and quickly sharpen these scissors yourself - even as a beginner.

57 - 59 HRC = high quality cutting steel
The steel is hardened using special hardening processes and grinding techniques
The upper blade class (70 - 150€) has a blade hardness of 57-59 Rockwell.

Here too, the scissors are usually forged in one piece from X50CrMoV15 and are additionally hardened and made more robust against acids using various techniques, for example blue plying, ice hardening or the Solingen thin section.

Such scissors are particularly interesting for beginners because they stay sharp for a long time - but can also be easily re-sharpened.

60 - 64 HRC = hard premium steel
As a rule, Japanese scissors and cutting edges are forged in this Rockwell area, but also Damascus scissors or special alloys such as the SUS440C steel we use.

These scissors are ground particularly thin, which is why they are extremely sharp. Such scissors are designed for professionals, as the sharpness of the blade is more of a disadvantage in the hands of a layman.

64 - 70 HRC = Japanese premium steel
Very few masters in Japan are able to forge such blades.

The hardest blade steel in the world (ZDP-189) consists of 20% chromium and has a carbon content of 3%.

Now you know when scissors are made of hard steel and when they are made of soft steel.

But what does the blade hardness say about the edge retention of the individual scissors and how long do scissors stay sharp?

2) Edge retention in groomer scissors

The fact is: the harder the knife steel, the longer the blade stays sharp, right? So in theory it is, but in practice it depends on you.

Why?

With a hard blade, there is less wear and the cutting edge wears out more slowly - you already know that. But if you use the scissors incorrectly, say:

  • Unclean cutting technique
  • unwashed fur
  • Incorrect storage

Then your scissors will dull even faster than a blade made of softer steel. How come? Because hard steel doesn't forgive mistakes.

In other words:

If you cut wet and unbrushed fur with 64 HRC scissors, the blade edge can quickly break.
If you cut dirty fur, the blade may collide with the harder particles in the fur and break out. If you cut improperly or use the wrong cutting technique, you can injure yourself and also damage your scissors.
By the way, in our seminars I show 21 cutting techniques with which you can cut like a professional and your scissors are guaranteed to stay sharper for longer.

But let's stay on topic:

Soft steel, on the other hand, is flexible and the cutting edge is not as resentful as a pubescent teenager - but rather quickly forgives mistakes because the cutting edge is not "at risk of breaking".

But: With soft steel, the seal is larger and a sharp blade doesn't stay sharp for as long - so you have to sharpen the blade regularly so that it stays sharp.

But how well can the different hardness levels be sharpened?

Let's take a look at this now:

3) How well can scissors be sharpened?


Mild steel is flexible and can therefore be sharpened back into shape or ground to the appropriate angle more easily. Hard steel is stubborn and can only be made sharp again by special grinders.

And once a pair of scissors becomes dull, two things happen.

1. First the blade becomes dull.
Before the scissors are dull and no longer cut at all, they are rather dull and can still just about cut one or two types of fur.

In this case, the cutting edge has a fine, barely visible curvature and is no longer pointed like a V - but more like a y (this curvature is called a burr). You can quickly get this back into shape and sharpen your scissors with a sharpening rod.

In other words: “bend” the cutting edge back into the pointed V shape.

With a blade hardness of up to 56/57 HRC, this is easy and even a beginner can do it with a simple sharpening steel.
But first, what happens if you don't sharpen your scissors in time?

2. Then the blade of the scissors becomes really dull.
The cutting edge rounds and the V-shape wears into a U-shape.

Then only one thing helps: grinding - i.e. removing material.

With soft steel up to 57/58 HRC this is easy and you can do it yourself as a beginner. A simple whetstone is enough for this.
In a (separate) simple crash course, I'll show you how to sharpen a dull blade extremely sharp.

But all of this becomes problematic from a Rockwell hardness of 59/60 HRC.

On the one hand, the blade steel is very hard - but also very sensitive.

So you not only need special tools such as a honing leather, ceramic rod or sharpening rod with diamond grit, but also the right technology. On the other hand, you can't sharpen hard steel (from 59/60 HRC), you can only grind it - at the right angle with the right water stone.

In other words: As a beginner, it's best to go to a professional sanding service.

The advantages and disadvantages of different HRC values

That was a lot of material and so that your head doesn't explode, I've made an overview for you.

Here are the pros and cons of soft and hard steel:

Mild steel 54 HRC - 57 HRC

Advantages

  1. Shatterproof - does not tend to break out in the event of impacts or dirty fur
  2. Versatile - you can cut soft and hard fur with the same scissors
  3. Beginner-friendly - ideal hardness for "beginners", as the knife edge does not break even if the cutting technique is incorrect
  4. very easy to sharpen and grind (sharpening steel and whetstone)
  5. flexible - you can theoretically also plane with the blade
  6. you can use the scissors for all your cutting techniques

Disadvantages

  1. you need to sharpen the scissors regularly to keep the blades sharp
  2. As a rule, the cutting edge can be ground at a maximum angle of ± 20° (the sharper the angle, the sharper the blade)
  3. you can't grind the cutting edge finely - so the sharpness has an upper limit
  4. Since the blade is used for general purpose cutting, wear is greater and the blade does not stay sharp for long

Harder steel 59 HRC - 67 HRC

Advantages

  1. ideal for precise and delicate cuts
  2. The cutting edge has an acute angle (approx. max. 15°) and is therefore extremely sharp
  3. The steel has little wear - so the blade stays as sharp as it was on the first day
  4. usually lighter than mild steel because the knife blade is narrower
    Particularly hard Japanese SUS440C steel (63+ HRC) can be ground extremely fine and sharp
  5. You only need to sharpen the scissors after a very long time
  6. meets all the sharpness requirements that a professional groomer has

Disadvantages

  1. the hard steel can quickly break if the scissors are used incorrectly
  2. no chopping possible - only precise and clean cuts possible
  3. To sharpen the scissors, you need special sharpeners (sharpeners, ceramic rods, water stones). You should only use them to cut well-groomed fur.
  4. the blade is rigid and inflexible - can break if hit

You notice: There are enough advantages and disadvantages with soft steel - and enough with hard steel. That's why there is no such thing as the "best" steel. The question is much more: Which scissors suit you best? And you can easily determine this from the degree of hardness for you.

That's why we ask ourselves the final question:

What Rockwell hardness should my scissors have?
Let's get to the point: can you use scissors or not?
If you didn't immediately answer the question with a YES, then scissors with 60+ HRC are not for you.

You need something to get you started. A good balance between hard and soft.

In other words: universal scissors with 56 - 57 HRC. That's why we developed our G-Start scissors. Thanks to special ice hardening processes and a traditional grinding technique, the blade is particularly sharp - and stays that way for a long time.

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