s30v

[db]

Again clearly, the makers who use such knives, does ANYONE contend that the performance of their knives is as embarassing as Hossom describes? Do the people using Tai's knives find their edges deflect and roll very easily? How about Stewarts 12C27M knives which are ground very acute at the edge?

Mike Stewart doesn't put the same degree edge on all of his knives, he puts what he believes to be the proper angle for the knife and it's design and use. However, he does like a convex edge put on held around 13 degrees per side, 26 ish degree edge, witch is a fair amount above a 20 degree edge.

How about Landes who notes his knives are at the 8-12 degree level for such steels?

Does Landes really put on a 4 degree per side,8 to a 12, 6 degree per side, edge on his large knives made as choppers?

How about dealing with ANY of the wide statement such as Hossom has noted which are directly contradicted by scores of makers.

How about you deal with your own comments and statements witch are contradicting, misleading, unclear, illogical, hype, and indirectly false in this thread, instead of worrying about a single phrase, you cherry pick of Jerrys or anyone elses in their post.

I have used multiple large knives out of low carbide steels for large choppers from guys like Kirk and the edges ae far under 20+ degrees per side and they do not deflect easily.

20 +degrees per side is way above a 20 degree edge, like double the thickness 20 +20 is 40. No one in this thread has stated that a 40 degree edge is deflected easily. Are you trying to change your 20 degree edge stability comments to a 40 degree edge? Is this another attempt to misdirect and divert the thread from your own statements?

 

[Steelhed]

Bastid is talking about one or both of the following logical fallacies in Cliff's statement:

Hasty Generalization - The size of the sample is too small to support the conclusion.

Composition - Because the parts of a whole have a certain property, it is argued that the whole has that property.

For example: X says he does not like S7 for choppers because he has found its properties unsuitable for that application, therefore other makers will not like S7 for choppers.

Jerry says he does not like a certain steel and would be embarassed to use it. Since Jerry is a maker, Cliff concludes that Jerry means all makers would be embarassed to use it. This is either a hasty generalization going from the specific (Jerry's dislike) to the general (all makers dislike), or a composition fallacy where one maker's opinion is extended to include all makers. Jerry's statement did not provide enough information to draw such a conclusion.

Yes, Cliff claims Jerry's use of the steel's properties are universal's that can be extended beyond Jerry's own experience and assertion, but as Bastid pointed out those properties can vary due to different treatment and application, and therefore Cliff's extension from the specific (Jerry's application of those properties) to the general (other makers' application of those properties) does not logically hold. Even if they did, we would still be unable to draw a logical conclusion about how other makers feel about the steel without asking them.

Now inferences are a different matter altogether. I think Cliff is on safe ground there.

 

[davmgt]

Now inferences are a different matter altogether. I think Cliff is on safe ground there.

only if he makes inferences about those knives/steel tested. Not on that steel or a type of knife in general. Experiments have limited external validity. Unless they can be replicated reliably you cannot make inferences on the general population -- only on the subjects tested.

 

[Steelhed]

davmgt - I was not talking about inferences regarding knives or steels, but emotional comments and who they may or may not refer to. As I'm sure you know, language has its surface meanings, but it also has deeper structure with psychological or emotional content. Sometimes our words mean many things on many levels, and while they may appear to be logically inconsistent on the surface they connect on a different level and the message is delivered. Most humor is based on this.

 

[davmgt]

Gotcha, man interpreting the nuances of language makes statistical inference look quite simple!

 

[Cliff Stamp]

The only thing that I can logically conclude from what was written, is that Jerry does not use the steel or like it for the knives he makes.

First when you say "As a chef ..." or whatever, you are stating clearly that the reason for your inference is that condition. This is obvious, and you continuing to ignore it does not change the fact. It would be no different than if I said "As a newfoundlander, I can tolerate extreme cold.". Yes, this implies that the REASON I can tolerate the cold is because I am a newfoundlander and the logical question would be "So is everyone like that?" Because if this is not true then your presupposition is of course false. Now in general people do not mean the absolute implications in terms of nationality, but work fields tend to be stronger, especially when so clearly stated.

However, as I have stated, this is the side semantic issue which you have chosen to blow up into the main arguement to avoid dealing with the FACTS. Hossom has attributed to 12C27M a number of properties. It is the properties that I am dicussing, you are ignoring those statements and trying to create a personal strawman. As for other factors, yes, there are differences in heat treatments but these do not make the kind of sweeping differences you imply which would make such comparisons impossible.Your arguement even contradicts itself because the whole point of this thread was to generalize about a steel in the first place.

If you actually read work on steels such as by Verhoeven you will see him, a very well respected metallurgist who focused significantly on knives, make the exact same generalizations I have made here. In fact I will quote him:

"From this discussion it appears that the two steels discussed in Chapter 13, Uddeholm AEB-L and Sandvik 12C27, along with the similar steels of Table B1, (DD400 and AUS6) provide the best combination of properties desired in a knife blade:"

Now would you respond to this with an attack on that it is illogical to say this for the reasons you noted? Because if he did all he would say is "I am assuming the knife makers are competent heat treaters and can maximize the properties in the steels." I assume that is true about people like Tai Goo, Ray Kirk, etc. .

I will repeat clearly, Verhoeven notes AUS6 is SUPERIOR to 440C/154CM. Now when I say this here, a position based on FACTS, it will generate a load of posts about personal inferences, thus logically all of those same rants would have to be directed at Verhoeven (he is also ignorant, crazy, etc.) as he says the same thing unless of course they are simply personal bias and have nothing to do with the FACTS presented.

X says he does not like S7 for choppers because he has found its properties unsuitable for that application, therefore other makers will not like S7 for choppers.

Assuming they require those properties, yes that would follow unless X is incompetent in heat treating or grinding.

-Cliff

 

[Frank Hillary]

Hi,

Hardheart: Thanks for that explanation and that link to that older tread. Meybe I mised something but I still do not undesrtand what exactly is "edge stability". From my work as a toolmaker I would have thought that whatever edghe stability is it would be mostly depend on the edge angles. Coukld Cliff explain please?

And it seems to me that from what Cliff is saying that steels like 440c and SV30 perform better with heavier edges. Is there a minimum angle above which they are OK?

Best Regards
Frank

 

[zenheretic]

If I was to ask questions, I would ask folks that actually have experience making the item in question.

 

[Cliff Stamp]

I still do not undesrtand what exactly is "edge stability".

Edge stability is the ability of a steel to resist microchipping/deformation. The higher the edge stability the thinner the cross section which is required to be stable. Steels with a very high hardness and very low carbide volume have a high edge stability.


-Cliff

 

[Frank Hillary]

Hi Cliff,

Thanks for that. How hard and how thin?

I mean if you temper a piese of steel it wont be all that hard, cant be can it?

Best Reagrds
Frank

 

[enderwiggin]

Has anyone seen any studies on 420hc from an impartial testing laboratory?

I tried alluding to this earlier, but it surprises me that a study done by a maker who uses 420hc a majority of their knives is considered valuable or 'scientific' ab initio.

 

[Bastid]

First when you say "As a chef ..." or whatever, you are stating clearly that the reason for your inference is that condition. This is obvious, and you continuing to ignore it does not change the fact. It would be no different than if I said "As a newfoundlander, I can tolerate extreme cold.". Yes, this implies that the REASON I can tolerate the cold is because I am a newfoundlander and the logical question would be "So is everyone like that?" Because if this is not true then your presupposition is of course false. Now in general people do not mean the absolute implications in terms of nationality, but work fields tend to be stronger, especially when so clearly stated.

There is no way I can come to a logical conclusion to generalize in that matter. As xxx, I do not use, like etc. YYY therefore all who are xxx feel the same is not logical.

I have made a decent living for over 30 years applying logic every day and that assumption is false by any logic standards. It just does not hold up. Logic, assumptions and implications do not mix well if you are looking for a correct logical outcome. Your use of "implies" and your assumptions of what was "implied" even re-enforces that your position is not based on logic, but implications and assumptions on your part.

 

[Cliff Stamp]

Thanks for that. How hard and how thin?

I mean if you temper a piese of steel it wont be all that hard, cant be can it?

Maximum is 66 HRC or so. Yes, all hard, 1/16", 0.005" at the edge, hollow ground, 1/4" back from the edge it is 0.015" or so. That is for cutting knives, not chopping obviously.

As xxx, I do not use, like etc. YYY therefore all who are xxx feel the same is not logical.

It is not about simply subjective terms it is about PROPERTIES. Once you say, "Given my experience as a materials engineer, xxx is not suitable because the yyy ability is too low. It is in fact an absurd choice." this is obviously subject to the counterstatement I used.

-Cliff

 

[Cliff Stamp]

Meybe I mised something but I still do not undesrtand what exactly is "edge stability".

Ref :

http://www.bladeforums.com/forums/showthread.php?t=344902

-Cliff

 

[Bastid]

Cliff,

Once implications are used. Logic is no longer a basis for conclusions since the conclusion has not taken into account all paths to a conclusion.

That is basic.

 

[Cliff Stamp]

Bastid,

FACT presented :

Steel has property X

Arguement thus made dependent on that property:

Steel has usability label Y
Maker has viewpoint/label Z on such knives

Conclusions on other knives with such properties :

Maker has viewpoint/label Z on such knives.

Unless as I noted the arguement is NOT dependent on the properties and indicates a simple personal bias.

-Cliff

 

[Bastid]

This is where logic was left behind.

Maker just made the point that he did not like the steel on His knives.

You created the implication:

"Conclusions on other knives with such properties :

Maker has viewpoint/label Z on such knives."

Maker has veiwpoint on his knives. Not such knives. Anything past that is a conclusion based on an implication with no logical basis.

No need for me to argue any more since basic logic has quite obviously not been applied and the examples you cited do nothing but prove that the conclusion was based on implication and assumption.

 

[hardheart]

Well, while waiting to get back on topic, I went ahead and cut some 8 penny, hot dipped galvanized ring shank nails, Grip Rite brand (with nail QC as it is, I was able to find fairly smooth sided nails in the box for the cutting). I struck the spine of each knife with a 32 oz ballpein hammer.

Made 4 attempts with the small Junkyard Dog framelock, 13C26 blade. Failed twice due to error on my part, allowing the blade to turn while striking it with the hammer. These took out semi-circular chunks, 1.5 deep x5 mm long & 2 mm deep x 7 mm long. But I also cut through a nail twice, only rippling the edge when striking the knife squarely.

One attempt with a Schrade Century swiss army knife knockoff, made in Germany. Nondescript stainless, I had it scraping hair sharp before this 'test'. Cut through the nail in half a dozen blows. Almost no visible damage to the very edge itself, it appears straight when viewed from profile; but the entire section that cut through the nail is a single ripple, about 2 mm long and 1mm high, putting it into the primary grind. You have to catch it in the light, but the mirror-polished blade really shows it off.

M2 blade made from a power hacksaw blade, made it myself for no good reason . Broke out sections of the edge on two attempts, for the same reason the JYD did, the blade would deflect sideways because of poor grip. I was bout halfway through the second nail when I screwed up and took out a 5 mm section of the edge.

CPM154 kitchen knife, custom. Made sure not to let this one shift around on me, though even for a handmade it's affordable ($100). Cut through one nail, but chipped out the edge on the last blow, 2 mm across and 1 mm high, which is the top of the edge bevel.

I would have checked a Byrd Cara Cara in 8Cr13MoV, but the spine is curvy and leaves me no good place to strike.

I would do pics, but the macro on my camera doesn't work close enough for me to really show the more minor damage to the JYD & Shcrade. I actually can't even get a nice shot of the chip in the CPM154

 

[JCaswell]

Well, while waiting to get back on topic, I went ahead and cut some 8 penny, hot dipped galvanized ring shank nails, Grip Rite brand (with nail QC as it is, I was able to find fairly smooth sided nails in the box for the cutting). I struck the spine of each knife with a 32 oz ballpein hammer.

Made 4 attempts with the small Junkyard Dog framelock, 13C26 blade. Failed twice due to error on my part, allowing the blade to turn while striking it with the hammer. These took out semi-circular chunks, 1.5 deep x5 mm long & 2 mm deep x 7 mm long. But I also cut through a nail twice, only rippling the edge when striking the knife squarely.

One attempt with a Schrade Century swiss army knife knockoff, made in Germany. Nondescript stainless, I had it scraping hair sharp before this 'test'. Cut through the nail in half a dozen blows. Almost no visible damage to the very edge itself, it appears straight when viewed from profile; but the entire section that cut through the nail is a single ripple, about 2 mm long and 1mm high, putting it into the primary grind. You have to catch it in the light, but the mirror-polished blade really shows it off.

M2 blade made from a power hacksaw blade, made it myself for no good reason . Broke out sections of the edge on two attempts, for the same reason the JYD did, the blade would deflect sideways because of poor grip. I was bout halfway through the second nail when I screwed up and took out a 5 mm section of the edge.

CPM154 kitchen knife, custom. Made sure not to let this one shift around on me, though even for a handmade it's affordable ($100). Cut through one nail, but chipped out the edge on the last blow, 2 mm across and 1 mm high, which is the top of the edge bevel.

I would have checked a Byrd Cara Cara in 8Cr13MoV, but the spine is curvy and leaves me no good place to strike.

I would do pics, but the macro on my camera doesn't work close enough for me to really show the more minor damage to the JYD & Shcrade. I actually can't even get a nice shot of the chip in the CPM154

Sorry, but I only accept the anecdotal results of such unscientific methods when performed by qualified carpenters


Sorry, couldn't resist ...

 

[hardheart]