Spyderco Forums

I’m confused, because I thought that wear resistance was a function of hardness. You say that CruWear is tougher. You say it’s harder. (Usually hardness comes at the expense of toughness.) But you say that wear resistance of S35VN is better. I don’t get it. I really like the graphs of steel charact...

We stand on each others shoulders so we can see farther. Thanx much Larrin for the extra view. sal The book certainly wouldn’t have been possible without all of those before me who have made their contributions to the study of steel and knives. Always building on prior knowledge to be higher than w...

But once the processed sheet is sent to Spyderco, would it be true that there would be a small amount of untempered martensite formed at the surface level, from the grinding and polishing operations used to make a blade? Maybe, if they are using poor grinding and polishing operations there would be...

Yes, H1 is an austenitic steel - I can’t think of any other examples of non martensitic steels used in knife blades. I think Cliff Stamp did some experiments on sharpening and using an austenitic grade, some years ago, if I remember right. It is true that H1 is an austenitic stainless. However, it ...

The high hardness which Crucible’s testing reported at the edge for serrated edge H1, would seem like some sort of anomaly, from your explanation. Do you think this warrants any further investigation? Not particularly. The original claim of higher hardness at the edge didn't make much sense and an ...

I think I have said enough about H1 for now. Most of the questions being asked about H1 I already answered. Maybe people didn't like the answers. https://knifesteelnerds.com/2019/06/24/ ... -it-works/

Resistance to deformation is measured by hardness (not controlled by steel but by heat treatment). Resistance to chipping is measured by toughness. So asking which is the most stable but without toughness doesn't make any sense. An edge which loses cutting ability to either chipping or rolling is st...

It took a while to get it and take a quick look but Larrin's book is now on the shelf right next to "Tool Steels" which was pretty much the reference most makers interested in heat treating their own blades. It is also now a text book for students and practicing metallurgists. Larrin's book is of c...

Sorry if I got all that wrong. I'm just going on what I was told. It was a representative of Crucible that were at the BLADE Show back in 2005 I believe it was that told me that 440V (S60V) was made for the tool & die market. Not sure why the guy would lie to me :confused: But at the same time I re...

I agree with this logic as well Larrin, however I think that many of those tool steels are developed for industrial sheer types of blades where the cutting apex is a much larger bevel that the 30 to 40 degree angles we see with pocketable edge tools. Thus steels where edge stability is higher of a ...

It's always been amazing to me that certain types of steel that were made for certain applications. Take ATS-34 for instance>> I heard that it was first made for turbine blades in jet engines> and it was an American knife maker that discovered it to be a great blade steel with the right heat treatm...

Takefu does claim that VG10 was developed for knives: http://www.e-tokko.com/v_gold_10.php?lang=en

That's interesting. Is there an industry standard maximum allowance for sulfur content? Not really. Not unless there is a European spec I don’t know about. There may be specific industries like aerospace with more rigorous restrictions but for knife steel they are just making the steel with their n...

Mn and Si is in every knife steel so if they aren't listed it's just because the amounts aren't shown in the datasheet. Sulfur is usually not an intentional addition but an impurity, so some datasheets will list a maximum allowable amount. Thanks! So would you say the primary difference between REX...

According to Spyderco’s steel comparison chart ( https://www.spyderco.com/edge-u-cation/steel-chart/ ), they do seem to have very similar chemistry in terms of carbon, chromium, cobalt, molybdenum, tungsten, and vanadium. REX45 seems to have manganese, silicon, and sulfur, which are not included in...

Understood. With a CATRA machine, is there a way to conclude the test at a higher degree of sharpness so the "front end" can be isolated and measured? However... with the Sillica present in the card stock, there may not be a point in doing that, as I suspect that the stack rank would be approximate...

SubMicron wrote: ↑

Fri Aug 21, 2020 6:55 pm

What CATRA does not measure is the front end edge retention, especially through non abrasive materials, such as clean cardboard, cloth, tape, plastic, etc.

The CATRA test generates a full sharpness loss curve. It tests every stage including “front end.”

We will get something with true differentiation in performance eventually, I hope.

Hi Larrin, et all Another reason CPM S60 sort of faded out was the introduction of CPM S90V which was touted as an upgrade to S60V. S90V had everything S60V did plus after some fine tuning had better heat treat response. Yes , more resistance to finish but also somewhat better edge holding as noted...

Cambertree wrote: ↑

Mon Aug 17, 2020 6:28 pm

Thanks Larrin, I particularly enjoyed this article.

Awesome!