Dear Felix, in my Polymer-Career, 20 years ago I worked in shore-hardness. ;- ) I am also happy to let you know that I received a 2nd generation-sheath for my Victorinox Venture. Victorinox is still a great and generous company - I got it for free and I fee much more happy with it now. Best regards from Germany, my friend René
5:16 while the rockwell hardness scale varies from 0 to 100 for each given test type ( regular or superficial) and scale (A, B, C, etc), the scales have physical sensitivity limitations based on test design, and the ISO standard suggests applicable limits. Thus Rockwell C should only be used within the practical range of 20 to 70.
In Germany we dont have so many ways for the Rockwell Test Like in the USA. Here we use below 17 HRC the HRB/HB But i learned that over 20 years ago, maybe Germany now Accept more Tests too.
Many years ago I worked in a machine shop which often hardened components. The old timers didn’t go to the hardness tester, instead they gently rubbed an edge of the component with a fine file. They “felt” and “heard” how hard the metal had become by how well the file was biting in and removing a small amount of the material. This is almost the same principle as the hardness tester. Probably this is one reason why different knives “feel” different when we sharpen them on a coarse stone. Not a precise measurement of hardness of course, but it is a way for an ordinary person to compare a known blade with an unknown blade. Thanks for all you do Felix.
So very interesting. I’ve always liked the SAK ability to easily sharpen in the field. With today’s wonderful sharpeners I often wonder why the obsession with super steels and the super expensive knives. Victorinox makes what I think are the best traditional knives out there. Yes I’m a fan 😊 Great video Felix!
I also love the Victorinox steel, it holds a decent edge and is super tough. I really had to abuse the large blade on one as it was a job with difficult access and the SAK was all I could use, when I finished the blade was so bent the knife wouldn't close, I hammered it flat and I still use it in the garage 30 years later.
Danke Felix, sehr interessant, und ich hab auch keine Ahnung, wieso da unterschiedliche Prozente rauskommen. Ich tippe aber mal drauf, dass im Programm was nicht stimmt, denn die gedruckten Skalen sind ja alle identisch ... Hier in Indien scheint wohl das Brinell-Verfahren bevorzugt zu werden (jedenfalls bis 650, danach ist ja Schluss), das eine Kugel aus Carbid zum Messen benützt. Gemessen wird dann nicht die Eindring-Tiefe, sondern der Durchmesser der entstandenen Vertiefung. Gibt jedenfalls indische Standards, in denen die Werkstoffhärte in Brinell angegeben wird (z.B. der indische Standard für Billhooks IS3094 gibt als Härte 400-475 nach Brinell vor, erlaubt aber auch die Verwendung eines weicheren Stahls für die Angel). Die Härte wird, so weit ich das beurteilen kann, oft überschätzt, oder zumindest von den Herstellern oft in den Vordergrund gestellt, aber ein eher weicher Stahl, der daneben aber auch zäh und elastisch ist, kann ja in der Praxis viel besser taugen als so ein ultra hoch gehärtetes Teil. Die "weichen" Billhooks hier sind beispielsweise absichtlich so weich, damit sie nicht (aus-)brechen, wenn man mal einen Stein erwischt, und damit man sie mit jedem beliebigen Feldstein einfach nachschleifen kann. Wenn die Spitze mal verformt ist, hämmert man sie halt wieder hin, und das funktioniert üblicherweise ohne Materialverlust. Davon abgesehen bekommt man nicht so üble Schläge aufs Handgelenk, wenn der gesamte Apparat elastisch ist und die Wucht abfedert, mit der die Leute durchs (oder auf das) Gebüsch hauen. Und die Frage ist auch, wie die Härte überhaupt erreicht wird - also beispielsweise, indem ich den Stahl im Eiswasser- oder Ölbad härte, oder indem ich das Material mechanisch verdichte und so für eine höhere Härte sorge. Mein Opa saß oft da und hat seine Sensen gedengelt ... das war wie das Schleifen fast schon eine sakrale Handlung 🤣 Liebe Grüße aus Bangalore, Robert
Hallo Robert mein lieber Freund! Wie immer lacht mein Herz, wenn ich Post aus Indien bekomme. Danke für deine sehr interessanten Ausführungen. Ich hatte übrigens die selben Gedanken wir Du. Wenn die tabellen nicht einfach nur abgeschrieben sind, gibt's solche Tabellen hundertfach ... und was ich gesehen habe, weichen die nicht weit von einander ab.
Gentlemen, this is very interesting. I suspect the difference in the interval between the hardness on Felix’ scales was due to how they were calculated. That is, I suspect, one table calculated from a basis reference while the other had a a factor added to the previous number. Because they are not linear, the scale using the factor addition method had a small error that was inherited by each interval so it became amplified as the intervals were added to the scale. It is similar to stacking blocks of a certain size to fit space. The first several blocks may have an error so small that they all fit. But as the stack grows the errors stack up, too. Thank you for this education!
Hallo Robert, ich stimme dir vollkommen zu: Die Wahl des Werkzeugs hängt immer davon ab, was du damit erreichen möchtest. Im Alltag ist ein etwas weicherer Stahl oft sinnvoller als die für "Survival geeignet" beworbenen "Wundermesser". VG aus Deutschland😉
Zum Sensen dengeln. Verdichtet wird da im Sinne einer Steigerung der "Dichte", also des spezifischen Gewichts, nichts, weil physikalisch unter den Umgebungsbedingungen hier auf dem Planeten nicht möglich. Aber es wird kaltverformt. Durch Kaltverformung wird die sog. Versetzungsdichte erhöht. Versetzungen sind Fehler in der Gitterstruktur des Metalls. Näheres Hierzu: de.wikipedia.org/wiki/Kaltumformung Unter "Folgen" steht auch was zum Dengeln von Sensen.
Thanks for explaining something that I have long suspected to be the case. I once had a batch of 3 knives come back from Bohler Steel after hardening, and was told that the scale measured at 61 HRC. When it came to sharpening the blades it was MUCH more difficult than usual (57 HRC), and I often wondered why there was such a massive difference. Now I know! Thanks a ton for that, Felix. One of your very best videos. Cheers mate!
Excellent informative video, I was aware that the HRC Rockwell scale wasn't linear but didn't know why. Interestingly my grandfather worked his whole career at Vickers Armstrong Ship Yard on the River Tyne in Newcastle UK. this is the same Vickers that developed the Vickers hardness scale.
Very enlightening. I do not know where this cult of Rockwell came from but I am sure it was never much used when knives were a simple tool you used, and sharpened and then replaced when there was no steel left to sharpen. My mum was a cook and I still have one of her Sabbatier paring knives and there is not a lot of blade left on it.
Very interesting Felix and thanks. My aging brain can no longer cope with complex mathematics, but the HRC depends on pressing a Cone (a 3 dimensional object where the volume depends upon an exponent of 3) into steel whereas only measuring the depth (which is a single dimension) ignores the "volume" displaced. The difference (I think) would be logarithmic. Additionally, as the cone presses into the steel, some of the steel is smashed to the side of the cone (away from the center) and some of the steel is smashed into the depth of the hole. Thus, the Rockwell test compresses the steel, which alters its hardness the deeper it goes and the scale is no longer linear. I need a younger mathematician and metallurgist to express it better though.
Hello Randy. Thank you so much for your super interesting Comment. I am sure your are right! My brain was smoking for this video. This is a very complex topic... and i felt, that i step on thin ice 😄
@@FelixImmler I can definitely relate to your third and fourth sentences ... and I thank you for your first two! :D LOVE your videos and presentation "style" !!
According to wikipedia indentation hardness correlates linearly to tensile strength. Material science is very complicated so its typically simplified as a trade off between edge retention (which is related to hardness) and toughness which decreases in relation to hardness. New metallurgical techniques like the powdered metal techniques have changed this and have created steels that are both hard and tough but only by small to moderate amounts
Felix, you've once again explained things simply and well. There's also the depth of the hardening to consider. Some early Gewher 98 rifle receivers met the hardness standard, but in use were discovered to 'set back' or dent at the locking lugs because the steel underneath the hardened surface was too soft and was 'hammered back' in the rifle's use with the hardening intact!
Sehr interessantes Thema! Gern mehr in Sachen Materialkunde und Materialeigenschaften sowie Testverfahren. Auch wenn's alles andere als einfach zu verstehen ist! Aber wenn man nicht völlig an der Oberfläche schwimmen will ist das halt so. Solche "Erklärungsfime" sind sehr wertvoll. Vielen Dank dafür!
Hi Felix. You can also take into account CATRA edge retention and compare those figures. The numbers for CATRA represent how many layers of medium is cut through so it’s a good one-to-one comparison. I love this video though. Good job!
11:44 while there are many comparisons between Vickers and other indentation hardness scales, only the Vickers and Brinell hardness scales correlate well over a wide range. Regardless, using indenter test results to directly estimate bulk material properties such as tensile strength tend to be unreliable, being widely viewed that the procedure cannot be used with any confidence.
I came for the video, but I stayed to read the comments for all the 'experts' comments! I wasn't disappointed in either! 🤣 Thanks for posting Felix, I love your videos!
Hi Felix, I don‘t know why there is a diffence from 10-14 %. But from my work with steel I know that there is not only the hardness. There is also flexibility and an elastic moment that steels have, because of their ingredients and the way they were hardened and tempered. So from my opinion, this way of measuring is not very exakt. Vickers, Rockwell and Brinell tried to find a way to standardize the hardness proof for steel production. That was long time ago. Thank You for the video and please go ahead with exploring! Best regards from the Bavarian Forest -
Moin Felix, das war alles sehr interessant....super das du diesem Thema soviel Aufmerksamkeit gewidmet und alles auch nachvollziehbar erklärt hast.....da kann man viel mitnehmen! Ich selbst gehöre übrigens eher zu den Leuten, die eher selten über den HRC Wert reden.......auch ein Messer mit einem vergleichsweise niedrigen Wert kann ganz wunderbar funktionieren. 🙂 Stay sharp & allerbeste Grüße, Stephan
Hallo Stephan. Ja, da hast Du natürlich Recht. Der HRC-Wert ist nur ein Stein im Mosaik eines gut funktionierenden Messers. Und wer mit Diamanttools nachschärft, dem kann die Rockwellzahl sowieso ziemlich Schnuppe sein 🤣 Danke für deinen Kommentar. Mein Herz lacht immer wenn ich von Dir lese. Liebe Grüsse vom Bodensee
Toll erklärt, lieber Felix!👍👍👍 Als Qualitätsprüfer ist die Härtemessung auch ein täglicher Begleiter in meinem Beruf. Ich habe übrigens auch schon mal die Härte bei einer Klinge eines Victorinox "Swiss Army Knife" gemessen. Es waren knapp 58HRC! 👍👍👍Meine Firma hat diese schönen Messer mit Firmenlogo als Werbegeschenke für gute Kunden geordert. Natürlich musste ich auch eines für meine Sammlung haben.😁 Liebe Grüße und ein schönes Wochenende aus Österreich!
Hallo Willi. Ufff, da bin ich froh, das ich nicht einen totalen Shit erzählt habe. Ich habe aber durch das Studium für dieses Video auch einen Eindruck erhalten, wie difficile so eine Rockwellmessung ist. von 56 auf 58 Rockwell sind 4 tausendstel Einsinktiefe. Der Konus nicht 100% im rechten Winkel zur Oberfläche kann diese Differenz bereits ausmachen. LG
@@FelixImmlerja, absolut und auch die Materialdicke, das Messgerät und noch einige andere Parameter können das Ergebnis verzerren. Übrigens wird nicht jede HRC-Messung mit 150Kg Einpresskraft durchgeführt. Für empfindliche, etwa polierte Oberflächen gibt es auch die 15Kg Messmethode, die kaum Spuren auf der Oberfläche hinterlässt. Aber egal wie und womit, die Victorinox-Messer sind einfach Kult und qualitativ absolut Top!👍
Wouldn't it be possible to calculate the volume of material displaced during a Rockwell hardness test using the force, tip angle and the depth of penetration? Even I'm not sure where I'm going with this... 😄 I suppose I was thinking more precise hardness comparison testing should be possible without resorting to measuring diagonals under a microscope. Maybe I still don't understand how the Rockwell testers work, but if you can measure penetration distance, the force applied is constant, the tip angle is known... why can't you create a scale that varies based on material displacement instead of just penetration depth?
Yes but the Problem is that the % different of 3% for 56 and 59 HRC in Volume is only 1.63% The Volume is = (1/3)*π*r²*h But you need to find r with Pythagoras there is r=b and h=a b = a * Sin Beta / Sin Alpha V56= 0.00214090743 mm³ V59= 0.00173217366 mm³ If i also calculate Vmax for h=0.2mm then i can rebuild the HRC Formular...and get for V56 = 91.48... V59 = 93.11... The good part of the original HRC is that a mechanic scale can Show the HRC Instant No need to meassure or calculate. For the HRC Test i can say its a bit more to it then you See Here, the Tip is rounded and you have a start Wight that stays and then you Set the scale to Zero and add the Main Wight. Wait for the Scala to stay and remove Main Wight, now read the Scala. Thats to be Sure the Probe is flat and No slag, plus elastic from the Probe is removed. (I Hope my math is correct because its over 20 years i Last used that;-) Greatz from Germany and have a nice Day opo
Hoi Felix, very nice and cool, that you are taking the "some kind of dry" theme of steel-hardness in a nice and simple understandable video! And you did it very well, thank you! LG
Yes, yes. Rockwell, Vickers and Brinell. A short side trip to materials science would be good for some of these "knife scientists" on YT... Thank you for this explanation!
Hallo Felix, that is wat i ever told also by the Kitchen and Professenal Knife. 1 ° HRC higer its much harder to sharpen and also to working with the honing Steel. For a Knife over 60° it is necessarie Spezial Honing Steels. Greatings Urs
Hallo Felix, danke Dir. Wieder ein sehr gutes lehrreiches Video. Da habe ich mir noch nie Gedanken drüber gemacht und es war interessant das mal so gut erklärt zu bekommen. Hab eine schöne Woche. VG Eric.
Great video Felix! I love it when someone asks simple but important questions and in doing so busts or at least highlights truisms that need further looking into. It would be great if you and OUTDOORS55 could make a video together and look into this in even further detail.
So I went to his TH-cam page and asked him. Fingers crossed, I'd love to see you two guys doing a video on this together! All the best to you and carry on the great work.
@@nickjanczak9665 Nick, I absolutely agree with your second sentence AND your wish to see a collaboration. That would be very interesting indeed - IF I can keep my brain from exploding.
But wouldn't you be able to derive the same area calculation that the Vicker's uses from the depth measurement of the Rockwell method? Wouldn't the area of the indention of the Rockwell method be directly related or a function of the depth of the indention? Is it not just stating the same thing in a different way?
Moin Felix! Danke für die Klarstellung. Ich kenne Vickers aus dem Uhrenbereich. Wenn dort von 1200 Vickers Härte gesprochen wird, ist es unwahrscheinlich, Kratzer auf dem Gehäuse zu bekommen. Vielleicht sollten wir Bereich der Messer auch auf Vickers gehen. Es müsste ja nicht gleich jede einzelne Klinge gemessen werden, wie bei Puma. LG Claus
Precisely - it is a logarithmic progression! I was trying to think of an example; loudness in decibels is perfect. I think earthquake magnitudes are the same. Thanks, Darius!
The fact is that a person distinguishes differences in loudness not linearly. The loudness of sound for the human ear has a lagorithmic dependence. By the way, this also applies to the brightness of the light in lumens.
@@christophggcyrus6861You've got that one right. I agree. Population growth, technology, etc. I reckon that's why my aged 'n brittle brain struggles to keep up! At least I have Felix & you guys to sort things out for me and keep 'em simple! :D
Even though I learned about hardness, I miss the projects you made with the SAK. Will we ever see videos about making things? The Nativity was my favorite.
The aerospace industry generally utilise ASTM E140 for correlation purposes. However, the 2 hardness methods are not directly comparable as the correlated values are obtained via experiment and therefore multiple variables need to be considered. The approach should be that the values when compared are ‘apparent’ and not ‘absolute’.
Ich habe mir eben mal die Volumenformel des Kegels (= Konus) vorgenommen und das Verhältnis zwischen Eindringtiefe und verdrängtem Volumen ist sogar noch eine Potenz höher, als Du sagst. Bei verdoppelter Eindringtiefe vervierfacht sich die Grundfläche des Kegels, während sich das Volumen sogar verachtfacht! (1/3 * r * r * pi * h vs. 1/3 * 2r * 2r * pi * 2h!) Das erklärt möglicherweise die Diskrepanz zwischen Rockwell, Vickers und dem Härterechner: Rockwell berücksichtigt die Eindringtiefe (1. Potenz), Vickers die Grundfläche der Pyramide (2. Potenz) und der Rechner vielleicht des Volumen (3. Potenz)?
Danke für dein super interessantes Feedback! Ich bin nicht das hellste Kerzlein auf der Torte, darum war ich schon mit einfachen Fragen zu diesem Thema überfordert. Ist die Mantelfläche relevant, wenn's um die Verdrängung von Material geht oder das Volumen?
Vielleicht ist auch die sehr grobe Rundung auf der Vergleichstabelle bei den Vickerswerten in 10er Schritten für einen Teil des Diskrepanz verantwortlich.
@FelixImmler Sehr berechtigte Frage, die kam mir auch. Mit zunehmender Mantelfläche nimmt der flächenbezogene Druck ab, aber das Material muss ja auch verdrängt werden, das ergibt dann evtl. Scherkräfte im Stahl(?) Da bin ich jetzt weit außerhalb meiner Expertise, aber es macht Spaß, darüber nachzudenken und Antworten zu suchen.
Beim Vergleich von Rockwell und Vickers denke ich das es zu Unstimmigkeiten in der Tabelle kommen kann wegen dem elastischem Bereich des geprüften Materials. Bei Vickers wird am Ende der Abdruck gemessen an der Oberfläche. Bei Rockwell wird das grund Gewicht immer drauf gelassen und das zusätzliche Test Gewicht wird aufgelegt und dann abgenommen. Ich tippe darauf das im Material der Elastische Teil sich verändert je nach Dicke des geprüften Materials bzw. Eindringtiefe. Da der Rockwell Test ja extra dazu gedacht war den elastischen Teil nicht mit zu messen.
Looking at the tabular, I m surprised. If one scale would be linear and the other exponential, the steps between each RC should increase continuously on the Vickers scale. But I see a swinging between 10-30-15-30… Can someone explaine this to me?
Yes you are right. I saw that also. But in the tendence the steps growes as harder the material is. In my opinion, the table is very imprecise and is rounded to 10/15 increments at Vickers
No hardness testing system for commercial application starts at "no resistance at all" (= free fall), they all start at a range that makes sense for their intended application. Vickers starts out lower than Rockwell, Janka starts lower than Vickers, Shore-A starts lower than Janka etc, because they are intended to test different materials. That's why a 10% difference between Vickers and Rockwell can actually be a 14 % difference, and so on.
Thanks for the video! It's fascinating when you start looking into all the physical properties of steel. HRC is just the tip of the iceberg! There are two more critical parameters: toughness and abrasion resistance. And the correlation between all of them is not straightforward at all!!!
Félix about utilities to hard it is more chance to brake ..my friend bush man dint like the ax because the file dint grab to sharpe it ..that people that really used axe’s to daily life I had that situation also whit a trapper..you can talk about the utility of deferent hrc
Hi Felix! There must be some explanation as to why there is a variance between the Rockwell - Vickers Table and the calculator. It would seem there is a piece of the puzzle missing.
Hey @@FelixImmlerget hold of victorinox. Let them know we got their next money maker.🤔😳🤯 "The Swiss Zombie Knife" Make it neon green and add a 6 inch Marlin spike! Lol!!
Hallo Felix!Felix,du hast Verbindung mit der Entwicklungsabteilung von Victorinox. Kannst du bitte einen Gefallen tun, um eine Idee zum Victorinox Ingenieuren weiterzugeben? Ich arbeite als Elektro-Prüfer (bzw.ortsveränderliche elektrische Betriebsmittel prüfen).In dieser Hinsicht muss ich mehrmals am Tag die Plaketten wechseln, alte entfernen und neue wieder aufkleben. Deshalb hätte ich gerne so ein Universalwerkzeug, bei dem es eine große Klinge, eine Klinge zum Abisolieren von Drähten und einen kleinen Seitenschneider gäbe und vor allem ein Schaber für Etiketten entfernen.Ich denke, ein solches Werkzeug wäre sehr gefragt, da es alles enthält was für diese Arbeiten notwendig ist. Vielen Dank im Voraus
Mit einem HSS-Bohrer, den du vorher auf helle Rotglut erhitzt und dann in Eiswasser getaucht hast, bohrst du durch ein HRC58-Messer wie durch Butter. Gruß Karl.
@@FelixImmler Ja, deshalb entsprechend vor Splitter schützen. Auf die gehärteten Bohrer male ich einen roten Ring, damit ich die Vorsicht nicht vergesse.
Fun thing is that to feel in hardness when snarpening, the hardness difference needs to be more than 10 or 15%. To manually feel that difference it should more like 30-40%
It occurred to me that having a few cheeper knives is better than having one good knife. If you have two it matters not how long it stays sharp because you could have someone sharpening one wile you use the other. If you only had one good knife you would have to stop working to sharpen. 😃
So long as by 'cheap', you don't also get 'weak'. I'd rather have one good knife than two with snapped blades. I suppose the answer is to have two 'good' knives.
MERCI. Très intéressant. Ne peut-on trouver un algorithme qui permette de mesurer non linéairement les Rockwells ? THANKS. Very interesting. Can't we find an algorithm that allows the Rockwells to be measured non-linearly ? DANKE. Sehr interessant. Können wir nicht einen Algorithmus finden, der eine nichtlineare Messung der Rockwells ermöglicht ?
Reading charts and test results are interesting but only are numbers. However, there a few tests you can do yourself on your own knife if you want to know. There are testing file sets available that are harden to set HRC standards. Machinist often uses them to check unknown types of metals. It is reference to set turning speeds for cutting materials. The ones I looked at run from 65 to 40 HRC, By drawing the file across the metal surface it will scratch the surface if not as hard as the file. If it is harder, it will not scratch the surface, how accurate they are is subject I would not know.🤔👍
Unlike so much of TH-cam - here there is always something new and informative
Thank you so much for your compliment!
It takes a skilled instructor to explain complex topics simply.
Thanks a lot for this wonderful feedback!
@@FelixImmler well earned, Sir.
That reminds me of this saying:
"If someone can't explain something in simple terms, they don't really understand it all that much themselves."
Dear Felix,
in my Polymer-Career, 20 years ago I worked in shore-hardness. ;- ) I am also happy to let you know that I received a 2nd generation-sheath for my Victorinox Venture. Victorinox is still a great and generous company - I got it for free and I fee much more happy with it now.
Best regards from Germany, my friend
René
Dein Kommentar macht mich glücklich! Vielen Dank Rene!
Very interesting for all the knive lovers, I learned something new today. 🙏🏼
Super, that makes me happy! Thank you!
5:16 while the rockwell hardness scale varies from 0 to 100 for each given test type ( regular or superficial) and scale (A, B, C, etc), the scales have physical sensitivity limitations based on test design, and the ISO standard suggests applicable limits. Thus Rockwell C should only be used within the practical range of 20 to 70.
Thanks a lot for your interesting hint!!!
In Germany we dont have so many ways for the Rockwell Test Like in the USA.
Here we use below 17 HRC the HRB/HB
But i learned that over 20 years ago, maybe Germany now Accept more Tests too.
Many years ago I worked in a machine shop which often hardened components. The old timers didn’t go to the hardness tester, instead they gently rubbed an edge of the component with a fine file. They “felt” and “heard” how hard the metal had become by how well the file was biting in and removing a small amount of the material. This is almost the same principle as the hardness tester. Probably this is one reason why different knives “feel” different when we sharpen them on a coarse stone. Not a precise measurement of hardness of course, but it is a way for an ordinary person to compare a known blade with an unknown blade. Thanks for all you do Felix.
Thanks a lot for your super interesting comment!
So very interesting. I’ve always liked the SAK ability to easily sharpen in the field. With today’s wonderful sharpeners I often wonder why the obsession with super steels and the super expensive knives. Victorinox makes what I think are the best traditional knives out there.
Yes I’m a fan 😊
Great video Felix!
Thanks a lot for this wonderful compliment!
I also love the Victorinox steel, it holds a decent edge and is super tough. I really had to abuse the large blade on one as it was a job with difficult access and the SAK was all I could use, when I finished the blade was so bent the knife wouldn't close, I hammered it flat and I still use it in the garage 30 years later.
Danke Felix, sehr interessant, und ich hab auch keine Ahnung, wieso da unterschiedliche Prozente rauskommen. Ich tippe aber mal drauf, dass im Programm was nicht stimmt, denn die gedruckten Skalen sind ja alle identisch ...
Hier in Indien scheint wohl das Brinell-Verfahren bevorzugt zu werden (jedenfalls bis 650, danach ist ja Schluss), das eine Kugel aus Carbid zum Messen benützt. Gemessen wird dann nicht die Eindring-Tiefe, sondern der Durchmesser der entstandenen Vertiefung. Gibt jedenfalls indische Standards, in denen die Werkstoffhärte in Brinell angegeben wird (z.B. der indische Standard für Billhooks IS3094 gibt als Härte 400-475 nach Brinell vor, erlaubt aber auch die Verwendung eines weicheren Stahls für die Angel).
Die Härte wird, so weit ich das beurteilen kann, oft überschätzt, oder zumindest von den Herstellern oft in den Vordergrund gestellt, aber ein eher weicher Stahl, der daneben aber auch zäh und elastisch ist, kann ja in der Praxis viel besser taugen als so ein ultra hoch gehärtetes Teil. Die "weichen" Billhooks hier sind beispielsweise absichtlich so weich, damit sie nicht (aus-)brechen, wenn man mal einen Stein erwischt, und damit man sie mit jedem beliebigen Feldstein einfach nachschleifen kann. Wenn die Spitze mal verformt ist, hämmert man sie halt wieder hin, und das funktioniert üblicherweise ohne Materialverlust. Davon abgesehen bekommt man nicht so üble Schläge aufs Handgelenk, wenn der gesamte Apparat elastisch ist und die Wucht abfedert, mit der die Leute durchs (oder auf das) Gebüsch hauen.
Und die Frage ist auch, wie die Härte überhaupt erreicht wird - also beispielsweise, indem ich den Stahl im Eiswasser- oder Ölbad härte, oder indem ich das Material mechanisch verdichte und so für eine höhere Härte sorge. Mein Opa saß oft da und hat seine Sensen gedengelt ... das war wie das Schleifen fast schon eine sakrale Handlung 🤣
Liebe Grüße aus Bangalore, Robert
Hallo Robert mein lieber Freund! Wie immer lacht mein Herz, wenn ich Post aus Indien bekomme. Danke für deine sehr interessanten Ausführungen. Ich hatte übrigens die selben Gedanken wir Du. Wenn die tabellen nicht einfach nur abgeschrieben sind, gibt's solche Tabellen hundertfach ... und was ich gesehen habe, weichen die nicht weit von einander ab.
Gentlemen, this is very interesting. I suspect the difference in the interval between the hardness on Felix’ scales was due to how they were calculated. That is, I suspect, one table calculated from a basis reference while the other had a a factor added to the previous number. Because they are not linear, the scale using the factor addition method had a small error that was inherited by each interval so it became amplified as the intervals were added to the scale. It is similar to stacking blocks of a certain size to fit space. The first several blocks may have an error so small that they all fit. But as the stack grows the errors stack up, too.
Thank you for this education!
Hallo Robert,
ich stimme dir vollkommen zu: Die Wahl des Werkzeugs hängt immer davon ab, was du damit erreichen möchtest. Im Alltag ist ein etwas weicherer Stahl oft sinnvoller als die für "Survival geeignet" beworbenen "Wundermesser".
VG aus Deutschland😉
Zum Sensen dengeln. Verdichtet wird da im Sinne einer Steigerung der "Dichte", also des spezifischen Gewichts, nichts, weil physikalisch unter den Umgebungsbedingungen hier auf dem Planeten nicht möglich. Aber es wird kaltverformt. Durch Kaltverformung wird die sog. Versetzungsdichte erhöht. Versetzungen sind Fehler in der Gitterstruktur des Metalls. Näheres Hierzu: de.wikipedia.org/wiki/Kaltumformung Unter "Folgen" steht auch was zum Dengeln von Sensen.
Thanks for explaining something that I have long suspected to be the case. I once had a batch of 3 knives come back from Bohler Steel after hardening, and was told that the scale measured at 61 HRC. When it came to sharpening the blades it was MUCH more difficult than usual (57 HRC), and I often wondered why there was such a massive difference. Now I know!
Thanks a ton for that, Felix. One of your very best videos.
Cheers mate!
Your compliment makes me very happy! Thank you very much!
Just like my admiration for your terrific videos a much more than twice the value of videos I like only half as much! Thanks, Felix!
Thank you very much for this funny compliment!
Excellent informative video, I was aware that the HRC Rockwell scale wasn't linear but didn't know why. Interestingly my grandfather worked his whole career at Vickers Armstrong Ship Yard on the River Tyne in Newcastle UK. this is the same Vickers that developed the Vickers hardness scale.
Woww, what an interesting story. Thank you!
I was aware of this "problem", but I have never found such good analysis even with formulas. Very interesting, thank you!
Thank you for your feedback!
Very enlightening. I do not know where this cult of Rockwell came from but I am sure it was never much used when knives were a simple tool you used, and sharpened and then replaced when there was no steel left to sharpen. My mum was a cook and I still have one of her Sabbatier paring knives and there is not a lot of blade left on it.
Very interesting Felix and thanks. My aging brain can no longer cope with complex mathematics, but the HRC depends on pressing a Cone (a 3 dimensional object where the volume depends upon an exponent of 3) into steel whereas only measuring the depth (which is a single dimension) ignores the "volume" displaced. The difference (I think) would be logarithmic.
Additionally, as the cone presses into the steel, some of the steel is smashed to the side of the cone (away from the center) and some of the steel is smashed into the depth of the hole. Thus, the Rockwell test compresses the steel, which alters its hardness the deeper it goes and the scale is no longer linear.
I need a younger mathematician and metallurgist to express it better though.
Hello Randy. Thank you so much for your super interesting Comment. I am sure your are right! My brain was smoking for this video. This is a very complex topic... and i felt, that i step on thin ice 😄
@@FelixImmler I can definitely relate to your third and fourth sentences ... and I thank you for your first two! :D
LOVE your videos and presentation "style" !!
I thik that that's it so...
According to wikipedia indentation hardness correlates linearly to tensile strength. Material science is very complicated so its typically simplified as a trade off between edge retention (which is related to hardness) and toughness which decreases in relation to hardness. New metallurgical techniques like the powdered metal techniques have changed this and have created steels that are both hard and tough but only by small to moderate amounts
Thank you so much for this super interesting comment. You are right... and the tensil strenght goes more or less linear to Vickers...
Felix, you've once again explained things simply and well. There's also the depth of the hardening to consider. Some early Gewher 98 rifle receivers met the hardness standard, but in use were discovered to 'set back' or dent at the locking lugs because the steel underneath the hardened surface was too soft and was 'hammered back' in the rifle's use with the hardening intact!
Thanks a lot for your super interesting comment!!
Gewehr* 98
Sehr interessantes Thema!
Gern mehr in Sachen Materialkunde und Materialeigenschaften sowie Testverfahren.
Auch wenn's alles andere als einfach zu verstehen ist! Aber wenn man nicht völlig an der Oberfläche schwimmen will ist das halt so. Solche "Erklärungsfime" sind sehr wertvoll. Vielen Dank dafür!
Danke für das tolle Kopliment!
Hi Felix. You can also take into account CATRA edge retention and compare those figures. The numbers for CATRA represent how many layers of medium is cut through so it’s a good one-to-one comparison. I love this video though. Good job!
Thanks a lot for your very interesting feedback!
I'm always learning from you, experience and wisdom make you a great teacher.
Thank you so much for this wonderful compliment!
@ShannonRamos - amen! His perpetual cheerfulness (that I'd like to emulate) and humor help too!
Hi Felix. Thank you for the great explanation. I now understand how the Rockwell hardness system works
11:44 while there are many comparisons between Vickers and other indentation hardness scales, only the Vickers and Brinell hardness scales correlate well over a wide range. Regardless, using indenter test results to directly estimate bulk material properties such as tensile strength tend to be unreliable, being widely viewed that the procedure cannot be used with any confidence.
Thanks a lot for your super interesting feedback!
Hallo Felix, danke für die interessanten Ausführungen und die Links. Jetzt herrscht mehr Klarheit über HRC. LG Micha
Vielen Dank, dein Kommentar freut mich!
I came for the video, but I stayed to read the comments for all the 'experts' comments! I wasn't disappointed in either! 🤣 Thanks for posting Felix, I love your videos!
Thanks a lot for your comment!
Hi Felix, I don‘t know why there is a diffence from 10-14 %. But from my work with steel I know that there is not only the hardness. There is also flexibility and an elastic moment that steels have, because of their ingredients and the way they were hardened and tempered. So from my opinion, this way of measuring is not very exakt. Vickers, Rockwell and Brinell tried to find a way to standardize the hardness proof for steel production. That was long time ago.
Thank You for the video and please go ahead with exploring!
Best regards from the Bavarian Forest -
Thank you for taking the time and energy to create such an informative video my brother!
Love, Health and positive energy to you and your Family!
Woww, thank you so much for your kind words!
Moin Felix,
das war alles sehr interessant....super das du diesem Thema soviel Aufmerksamkeit gewidmet und alles
auch nachvollziehbar erklärt hast.....da kann man viel mitnehmen!
Ich selbst gehöre übrigens eher zu den Leuten, die eher selten über den HRC Wert reden.......auch ein Messer mit einem vergleichsweise niedrigen Wert kann ganz wunderbar funktionieren. 🙂
Stay sharp & allerbeste Grüße,
Stephan
Hallo Stephan. Ja, da hast Du natürlich Recht. Der HRC-Wert ist nur ein Stein im Mosaik eines gut funktionierenden Messers. Und wer mit Diamanttools nachschärft, dem kann die Rockwellzahl sowieso ziemlich Schnuppe sein 🤣 Danke für deinen Kommentar. Mein Herz lacht immer wenn ich von Dir lese. Liebe Grüsse vom Bodensee
Ich habe mich schon immer gefragt, warum die Vickers-Methode so wenig angewendet wird.
Dank Deiner super Erklärung weiß ich's jetzt!
Danke Frederik!
Toll erklärt, lieber Felix!👍👍👍 Als Qualitätsprüfer ist die Härtemessung auch ein täglicher Begleiter in meinem Beruf. Ich habe übrigens auch schon mal die Härte bei einer Klinge eines Victorinox "Swiss Army Knife" gemessen. Es waren knapp 58HRC! 👍👍👍Meine Firma hat diese schönen Messer mit Firmenlogo als Werbegeschenke für gute Kunden geordert. Natürlich musste ich auch eines für meine Sammlung haben.😁
Liebe Grüße und ein schönes Wochenende aus Österreich!
Hallo Willi. Ufff, da bin ich froh, das ich nicht einen totalen Shit erzählt habe. Ich habe aber durch das Studium für dieses Video auch einen Eindruck erhalten, wie difficile so eine Rockwellmessung ist. von 56 auf 58 Rockwell sind 4 tausendstel Einsinktiefe. Der Konus nicht 100% im rechten Winkel zur Oberfläche kann diese Differenz bereits ausmachen. LG
@@FelixImmlerja, absolut und auch die Materialdicke, das Messgerät und noch einige andere Parameter können das Ergebnis verzerren. Übrigens wird nicht jede HRC-Messung mit 150Kg Einpresskraft durchgeführt. Für empfindliche, etwa polierte Oberflächen gibt es auch die 15Kg Messmethode, die kaum Spuren auf der Oberfläche hinterlässt.
Aber egal wie und womit, die Victorinox-Messer sind einfach Kult und qualitativ absolut Top!👍
This was absolutely fascinating. Thank you very much for your research and amazing graphics and clear and concise explanation.
Your compliment makes me happy! Thank you!
Wouldn't it be possible to calculate the volume of material displaced during a Rockwell hardness test using the force, tip angle and the depth of penetration?
Even I'm not sure where I'm going with this... 😄
I suppose I was thinking more precise hardness comparison testing should be possible without resorting to measuring diagonals under a microscope. Maybe I still don't understand how the Rockwell testers work, but if you can measure penetration distance, the force applied is constant, the tip angle is known... why can't you create a scale that varies based on material displacement instead of just penetration depth?
very smart question! I understand your thoughts. I can't give you an answer. I hope someone else sees your question and can answer it better than me
Yes but the Problem is that the % different of 3% for 56 and 59 HRC in Volume is only 1.63%
The Volume is = (1/3)*π*r²*h
But you need to find r with Pythagoras there is r=b and h=a
b = a * Sin Beta / Sin Alpha
V56= 0.00214090743 mm³
V59= 0.00173217366 mm³
If i also calculate Vmax for h=0.2mm then i can rebuild the HRC Formular...and get for
V56 = 91.48...
V59 = 93.11...
The good part of the original HRC is that a mechanic scale can Show the HRC Instant No need to meassure or calculate.
For the HRC Test i can say its a bit more to it then you See Here, the Tip is rounded and you have a start Wight that stays and then you Set the scale to Zero and add the Main Wight. Wait for the Scala to stay and remove Main Wight, now read the Scala. Thats to be Sure the Probe is flat and No slag, plus elastic from the Probe is removed.
(I Hope my math is correct because its over 20 years i Last used that;-)
Greatz from Germany
and have a nice Day
opo
Thank you Felix, HRC explained very well.
Thanks a lot!
Hoi Felix, very nice and cool, that you are taking the "some kind of dry" theme of steel-hardness in a nice and simple understandable video! And you did it very well, thank you! LG
Your compliment makes me happy!
Ich habe gespannt deine Erklärungen gelauscht und wieder viel dazu gelernt. Tolles Video (wie immer ☺)! Mach weiter so und vielen Dank👍
Dein Kommentar freut mich sehr. Dankeschön!
Wie hoch ist HRC Härte bei den Victorinox Taschenmessern und aus welchem Stahl sind sie ?
Die Klinge ist ca. 56 Rockwell und aus 1.4110
Love - Honesty - Respect - No Fear - No Hate 💖💖💖
Thank you...
Yes, yes. Rockwell, Vickers and Brinell. A short side trip to materials science would be good for some of these "knife scientists" on YT...
Thank you for this explanation!
Thanks a lot for your comment!
Thank you Felix! Great video as usual. Cheers 👍
Thank you so much!
Greetings Felix. Very informative and interesting. Thank you for keeping us well educated.
Thanks a lor for your kind comment!
Hallo Felix, that is wat i ever told also by the Kitchen and Professenal Knife.
1 ° HRC higer its much harder to sharpen and also to working with the honing Steel.
For a Knife over 60° it is necessarie Spezial Honing Steels.
Greatings Urs
Hoi Urs mit dem grossen Hecht!! ich freue mich sehr von Dir einen Kommentar zu bekommen! Liebi Grüessli vom Bodäsee!
Thank you Felix. I never thought of the scale in this manner. I guess I didn't really understand it.
Thanks for your comment!
Thanks Felix, you helped me to understand that better.
Super. your comment makes me happy!
From a mechanical engineer > Nicely said. You might also explain what ductility is . ATB from a former employee of Rockwell International.
Thank you very much!
👍Doch, war interessant!
Hatte das mal vor xx Jahren auf der Berufsschule gelernt. Aber im ernst - danach habe ich das nie wieder gebraucht. 😄
Danke für Deinen netten Kommentar!
Thank you for the interesting video! Have a nice weekend!
Thank you very much for your positive feedback!
Hallo Felix,
danke Dir. Wieder ein sehr gutes lehrreiches Video.
Da habe ich mir noch nie Gedanken drüber gemacht und es war interessant das mal so gut erklärt zu bekommen.
Hab eine schöne Woche.
VG Eric.
Freut mich sehr! Danke Eric!
Great video Felix! I love it when someone asks simple but important questions and in doing so busts or at least highlights truisms that need further looking into. It would be great if you and OUTDOORS55 could make a video together and look into this in even further detail.
I would love it if Outdorrs55 made a video on this topic. Please ask him!!
So I went to his TH-cam page and asked him. Fingers crossed, I'd love to see you two guys doing a video on this together! All the best to you and carry on the great work.
@@nickjanczak9665 Nick, I absolutely agree with your second sentence AND your wish to see a collaboration. That would be very interesting indeed - IF I can keep my brain from exploding.
Thanks Felix learning something new is always a good thing. :)
Thank you very much!
Excellent video dear Immler
Thank you very much!
VERY interesting! Thanks Felix! 😎👍
Thank you very much!
But wouldn't you be able to derive the same area calculation that the Vicker's uses from the depth measurement of the Rockwell method? Wouldn't the area of the indention of the Rockwell method be directly related or a function of the depth of the indention? Is it not just stating the same thing in a different way?
Good question. I would say no, because the flat goes linear to the material strenght and the depth not.
Danke für dieses informative Video :)
Sehr gerne!
Very well structured explanation 🍀🔪👊
Danke für's Kompliment! Liebe Grüsse vom Bodensee
Moin Felix!
Danke für die Klarstellung. Ich kenne Vickers aus dem Uhrenbereich. Wenn dort von 1200 Vickers Härte gesprochen wird, ist es unwahrscheinlich, Kratzer auf dem Gehäuse zu bekommen. Vielleicht sollten wir Bereich der Messer auch auf Vickers gehen. Es müsste ja nicht gleich jede einzelne Klinge gemessen werden, wie bei Puma.
LG Claus
Hallo Claus. Danke für dein sehr interessantes Feedback!
Wow so great you figured this all out Felix thank you very much
Thanks a lot for watching my stuff.
It's the same with loudness in dB. 100 dB is not 11% louder than 90 dB. It's twice as loud! 10 dB = 2x difference.
Thank you very much for your interesting hint!
Precisely - it is a logarithmic progression! I was trying to think of an example; loudness in decibels is perfect. I think earthquake magnitudes are the same. Thanks, Darius!
The fact is that a person distinguishes differences in loudness not linearly. The loudness of sound for the human ear has a lagorithmic dependence. By the way, this also applies to the brightness of the light in lumens.
Let's be honest: the universe is not linear, it's logarithmic - the linear World is a illusion for us sheeples 😉
@@christophggcyrus6861You've got that one right. I agree. Population growth, technology, etc. I reckon that's why my aged 'n brittle brain struggles to keep up! At least I have Felix & you guys to sort things out for me and keep 'em simple! :D
Even though I learned about hardness, I miss the projects you made with the SAK. Will we ever see videos about making things? The Nativity was my favorite.
Yes, next week i will do a SAK project!
Thanks Felix. Another fascinating video. 🎸🔪
👋🔥✌️Hello, Felix. Thank's a lot for a New knowledge! 👍👍👌
Thanks a lot for watching my video!
...Brilliant, this, Thanks Felix!!!😀
Brilliant Felix! Thank you!
The aerospace industry generally utilise ASTM E140 for correlation purposes. However, the 2 hardness methods are not directly comparable as the correlated values are obtained via experiment and therefore multiple variables need to be considered. The approach should be that the values when compared are ‘apparent’ and not ‘absolute’.
Thanks a lot for your interesting comment!
Complimenti Sig. Felix; argomento molto ma molto interessante. Iscritto 👍👍👍
Ich habe mir eben mal die Volumenformel des Kegels (= Konus) vorgenommen und das Verhältnis zwischen Eindringtiefe und verdrängtem Volumen ist sogar noch eine Potenz höher, als Du sagst. Bei verdoppelter Eindringtiefe vervierfacht sich die Grundfläche des Kegels, während sich das Volumen sogar verachtfacht! (1/3 * r * r * pi * h vs. 1/3 * 2r * 2r * pi * 2h!)
Das erklärt möglicherweise die Diskrepanz zwischen Rockwell, Vickers und dem Härterechner: Rockwell berücksichtigt die Eindringtiefe (1. Potenz), Vickers die Grundfläche der Pyramide (2. Potenz) und der Rechner vielleicht des Volumen (3. Potenz)?
Danke für dein super interessantes Feedback! Ich bin nicht das hellste Kerzlein auf der Torte, darum war ich schon mit einfachen Fragen zu diesem Thema überfordert. Ist die Mantelfläche relevant, wenn's um die Verdrängung von Material geht oder das Volumen?
Vielleicht ist auch die sehr grobe Rundung auf der Vergleichstabelle bei den Vickerswerten in 10er Schritten für einen Teil des Diskrepanz verantwortlich.
@FelixImmler Sehr berechtigte Frage, die kam mir auch. Mit zunehmender Mantelfläche nimmt der flächenbezogene Druck ab, aber das Material muss ja auch verdrängt werden, das ergibt dann evtl. Scherkräfte im Stahl(?) Da bin ich jetzt weit außerhalb meiner Expertise, aber es macht Spaß, darüber nachzudenken und Antworten zu suchen.
Beim Vergleich von Rockwell und Vickers denke ich das es zu Unstimmigkeiten in der Tabelle kommen kann wegen dem elastischem Bereich des geprüften Materials.
Bei Vickers wird am Ende der Abdruck gemessen an der Oberfläche.
Bei Rockwell wird das grund Gewicht immer drauf gelassen und das zusätzliche Test Gewicht wird aufgelegt und dann abgenommen.
Ich tippe darauf das im Material der Elastische Teil sich verändert je nach Dicke des geprüften Materials bzw. Eindringtiefe.
Da der Rockwell Test ja extra dazu gedacht war den elastischen Teil nicht mit zu messen.
Interesante tema 😉 me a gustado la explicación y como siempre de 10 👌 saludos 🇪🇦
Thank you very much!
Super informative. Thanks!
Thanks for watching!
Great info, buddy! Cheers!
Thanks a lot!
Looking at the tabular, I m surprised. If one scale would be linear and the other exponential, the steps between each RC should increase continuously on the Vickers scale. But I see a swinging between 10-30-15-30…
Can someone explaine this to me?
Yes you are right. I saw that also. But in the tendence the steps growes as harder the material is. In my opinion, the table is very imprecise and is rounded to 10/15 increments at Vickers
Very Good! Excellent lesson. Tank's.
Thanks a lot for watching!
thank you for compering ♥
Thanks for watching!
Truly enjoyed this!
Thank you so much!
No hardness testing system for commercial application starts at "no resistance at all" (= free fall), they all start at a range that makes sense for their intended application. Vickers starts out lower than Rockwell, Janka starts lower than Vickers, Shore-A starts lower than Janka etc, because they are intended to test different materials. That's why a 10% difference between Vickers and Rockwell can actually be a 14 % difference, and so on.
Yes you are right. Thanks a lot for your super interesting comment!
Thanks for the video! It's fascinating when you start looking into all the physical properties of steel. HRC is just the tip of the iceberg! There are two more critical parameters: toughness and abrasion resistance. And the correlation between all of them is not straightforward at all!!!
Thanks a lot! You are right. This topic is never ending... 😄
Würd mich freuen, wenn du mal wieder so ein "The Escape" - Video, wie vor 7 Jahren, machen würdest.
Danke für einen Input!
Hello from Beautiful British Columbia Canada 🇨🇦
Morning Felix 😊❤
Thank you so much for your support!
Félix about utilities to hard it is more chance to brake ..my friend bush man dint like the ax because the file dint grab to sharpe it ..that people that really used axe’s to daily life
I had that situation also whit a trapper..you can talk about the utility of deferent hrc
Thank's. Great knowledge.
Thanks a lot for watching!
Thanks for the knowledge.
Thank you very much for watching my video!
@@FelixImmler you are welcome .
Did you try to reverse the input in calculator? Put 59 to 56.
yes i did. it's the same result....
@@FelixImmler hmm, no clue then.
Hi Felix! There must be some explanation as to why there is a variance between the Rockwell - Vickers Table and the calculator. It would seem there is a piece of the puzzle missing.
I think part of the difference is the rounding errors with Vickers. These numbers go in steps of 10, which is quite significant.
I can't be the only one that keeps hearing:
"swiss zombie knife"
🧟♂️🧟♀️🧟
🤔🤣😜
I don't share this problem 😄
That's hilarious 😂 😅😂
Hey @@FelixImmlerget hold of victorinox. Let them know we got their next money maker.🤔😳🤯
"The Swiss Zombie Knife"
Make it neon green and add a 6 inch Marlin spike! Lol!!
Hallo Felix!Felix,du hast Verbindung mit der Entwicklungsabteilung von Victorinox. Kannst du bitte einen Gefallen tun, um eine Idee zum Victorinox Ingenieuren weiterzugeben? Ich arbeite als Elektro-Prüfer (bzw.ortsveränderliche elektrische Betriebsmittel prüfen).In dieser Hinsicht muss ich mehrmals am Tag die Plaketten wechseln, alte entfernen und neue wieder aufkleben. Deshalb hätte ich gerne so ein Universalwerkzeug, bei dem es eine große Klinge, eine Klinge zum Abisolieren von Drähten und einen kleinen Seitenschneider gäbe und vor allem ein Schaber für Etiketten entfernen.Ich denke, ein solches Werkzeug wäre sehr gefragt, da es alles enthält was für diese Arbeiten notwendig ist. Vielen Dank im Voraus
Well that's opened a can of worms lol. Great video, very well explained
Thank you very much. You are right. you can close this can again and have a happy life 😅
Interesting video.
👌🙌
Thank you very much!
@@FelixImmler
Thank you☝ for the very informative video.
Mit einem HSS-Bohrer, den du vorher auf helle Rotglut erhitzt und dann in Eiswasser getaucht hast, bohrst du durch ein HRC58-Messer wie durch Butter. Gruß Karl.
Woww, was für ein geiler Trick! Er wird verdammt spröde sein.. aber auch sehr hart.
@@FelixImmler Ja, deshalb entsprechend vor Splitter schützen. Auf die gehärteten Bohrer male ich einen roten Ring, damit ich die Vorsicht nicht vergesse.
Awesome info thanks
Thanks a lot for watching!
interessant wäre mal ein "Stahl-Vergleich" z.B. zw. Victorinox & Leatherman
Danke für die Idee
Fun thing is that to feel in hardness when snarpening, the hardness difference needs to be more than 10 or 15%. To manually feel that difference it should more like 30-40%
as is said, the to make a relation from sharpenbility to hardness is super dangerous. But my gut feeling says the same as you.
It occurred to me that having a few cheeper knives is better than having one good knife. If you have two it matters not how long it stays sharp because you could have someone sharpening one wile you use the other. If you only had one good knife you would have to stop working to sharpen. 😃
You are absolutley right!😃
So long as by 'cheap', you don't also get 'weak'. I'd rather have one good knife than two with snapped blades.
I suppose the answer is to have two 'good' knives.
@@davehumpleby3440 most tasks that snap knives are not knife tasks.
Hurrä guät, dä Pädagog isch wiedermol voll durrä ko bim Erklärbär spilä : )
haaa ha haa, dä Erklärbär hät sich uf dünns Iis gwogt 😂
Super Infos in dem Video. Ich feier das hart (mind. 68 HRC 😉).
Gruß Chris
Danke für Deinen lustigen Kommentar! Ja, 68 Rockwell das ist schon ne Nummer 😀
MERCI.
Très intéressant.
Ne peut-on trouver un algorithme qui permette de mesurer non linéairement les Rockwells ?
THANKS.
Very interesting.
Can't we find an algorithm that allows the Rockwells to be measured non-linearly ?
DANKE.
Sehr interessant.
Können wir nicht einen Algorithmus finden, der eine nichtlineare Messung der Rockwells ermöglicht ?
I'm too bad at math for that.
@@FelixImmler
👊😅👍
Dear Felix, Thank you very much for all ! 🤗💙
Can you set a standard for us knife fans?
Haa ha haa Felixwell ??
@@FelixImmler who else could do it?
Thanks Felix, I had thought Rockwell may be logarithmic, but you have confirmed it.
Thanks a lot for your comment!
Thanks, great
Thanks for watching!
Goodnight❤❤
Thank you!
Of course we know ;-)
Congratulation! 👍
@@FelixImmler 🙃
thanks
Thanks a lot for watching!
Normally enjoy the SAKmeister video but this is too technical 🧐 If my blade cuts I'm happy enough.
You make nothing wrong... this is not important...
Reading charts and test results are interesting but only are numbers. However, there a few tests you can do yourself on your own knife if you want to know. There are testing file sets available that are harden to set HRC standards. Machinist often uses them to check unknown types of metals. It is reference to set turning speeds for cutting materials. The ones I looked at run from 65 to 40 HRC, By drawing the file across the metal surface it will scratch the surface if not as hard as the file. If it is harder, it will not scratch the surface, how accurate they are is subject I would not know.🤔👍
hallo Gizmo. Thanks a lot for your interesting comment!
Я ваш поклонник из Узбекистана
Good luck
So, this is hard to figure out?
For me yes... But I'm not the brightest candle on the cake 😄
@@FelixImmler It all comes down to F=mVV