an alternative way to classify stainless steels

Cliff Stamp said:
Those competitions, while extreme tests of maker skill do not place significant demands on wear, toughness or ultimate sharpness. Cashen noted awhile ago that the ABS smith tests could be passed by a mild steel blade and they included chopping a 2x4 and still shaving. Note for example the STIHL Lumbersports competitions, these are obviously highly skilled axemen, possibly the greatest speed, precision and raw power choppers in the world. The axe heads they use are cast stainless steel.
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I think you are unfamiliar with the competitions, sharpness is probably the number one thing tested. They aren't ABS tests, they are competitions. No one would win using mild steel.
 
Larrin said:
I think you are unfamiliar with the competitions, sharpness is probably the number one thing tested.
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Unless you are using a high polish and very low angles like 8-12 degrees per side, the steel won't limit sharpness. Even when these conditions are met it only constrains push cutting sharpness. You can achieve a very high slicing sharpness on even D2 which is one of the most coarse steels in both grain and carbide size. In fact you can even achieve a very high push cutting sharpness on such steels as long as the volume of work is kept small.

My point about the mild steel was that if you can take a mild steel blade and cut freehanding rope and chop a 2x4 and still shave then it is obvious that work of that type doesn't set a very discriminating standard for the steel. Most actual working blades such as parangs are left with pearlite structures because they are air cooled, not quenched/tempered. This of course doesn't leave them very hard but they are only sharpened about once a week and again these are working blades.

hardheart said:
Would the volume of blades being batch heat treated also be a factor? I figured the steels were left a few points below optimal just for fudge factor.
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Generally it isn't as much as intentionally leaving them soft as it is that everything which isn't done optimally tends to make blades softer. If for example the quenchant doesn't have a high enough volume or isn't well agitated, or there is significant time between the soak and the quench or the quench and cold treatment, or you don't actually use a quench and just air cool and no cold treatment. Of course it costs more money to do all of these things which is why it is much cheaper to just use a higher carbon steel which will get that hardness without any of that - of course the other properties are less than optimal.

-Cliff
 
Cliff Stamp said:
My point about the mild steel was that if you can take a mild steel blade and cut freehanding rope and chop a 2x4 and still shave then it is obvious that work of that type doesn't set a very discriminating standard for the steel. Most actual working blades such as parangs are left with pearlite structures because they are air cooled, not quenched/tempered. This of course doesn't leave them very hard but they are only sharpened about once a week and again these are working blades.
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I think you should talk to Warren Osbourne about his search for the perfect steel for cutting competitions, not any steel will do. I believe he used something like 30 different steels before he decided on CPM-M4. Some steels worked well for the first few times, but later would roll, break, or chip; he says you have to use one for a month to find out if it works.
 
Larrin said:
I think you should talk to Warren Osbourne about his search for the perfect steel for cutting competitions, not any steel will do.
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Talk to Kevin Cashen about what those cutting competitions "prove" about cutlery steels.

-Cliff
 
Cliff Stamp said:
Talk to Kevin Cashen about what those cutting competitions "prove" about cutlery steels.

-Cliff
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I am aware of Kevin Cashen's thoughts, but you are unaware of Warren Osbourne's. If you are not interested in furthering your knowledge then just say so.
 
what kinds of competitions are these? I have the November issue of Blade, and there is a story about one, but it seems more dependent on technique and geometry, even a little luck for one of the 5 events. I think the August issue (which I don't have) may have had more requirements for the competition blades, because it seems it would be easy to adjust the geometry of a 10" long blade along its length to handle the 5 tasks without failing at any of them. Of course, I've never done one of these competitions.
 
I have discussed the cutting contests in detail with makers who have both competed and won them, such as Kirk, including the specific methods used to sharpen and perform the cuts and even working with several knives he sharpened. As I noted, the cutting is an impressive test of user skill in regards to speed and especially precision. However if you actually wanted to use that cutting to test steels then you would have users who didn't make the blades do the cutting without knowing the steel or the maker. You would then be able to show if a steel could take a lower geometry and thus enable higher cutting performance if you saw a consistent pattern from user to user.

But considering that the makers are entering the contests and using them to promote the blade steels they sell you really can't consider them unbiased sources of information. Especially when the cutting is very sensitive to user skill. When you go buy a car do you actually ask the salesmen on the tests he has done on the cars and use this to make your choice? No, obviously not. In general you also have to set the bound on a test to discriminate based on the lowest pass. So which is the "least" steel to win defines what is necessary and this assumes that the makers are actually trying to do the competitions with the "least" steel.

-Cliff
 
I don't care how sharp my knife is, I wouldn't be cutting through any rolling ping pong balls. I hope the audience wears safety glasses.
 
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