Jerry Hossom said:
In both cases the total carbide content of the steels was deemed insuffient to provide the needed strength, resulting in the plastic deformation noted.
I realize Crucible is really strong on promoting high carbide volumes however the work done by Roman Landes and Verhoeven argues for a lack of primary carbides in the edges because they are far too coarse to provide any support for the steel and tear out in use and weaken the edge. Landes has micrographs showing this for various steels, it was the focus of his PhD thesis which was published, however unfortunately has not been translated yet.
Consider if this general hypothesis were true then steels like INFI would also readily deform at the edge as they have far less primary carbide than S30V. How about steels like S7, or AEB-L which has no primary carbides at all. Do you have any published materials data on 1V vs say 52100 which shows it is weaker at the same hardness? I would be interested to see specifically the torsional, compressional and tensile strengths especially in low cross sections.
Kohai999 said:
The evaluation of a blade, and not the wielder, can be tested, in rope cutting, by building a specialized machine.
What you have to be aware of when measuring is what is actually being measured. It is the actual variances in a person vs a machine which are critical to the evaluation. Consider for example if I built a machine which tested sneakers by applying a specific compressional load to the sole in a uniform manner and then a lateral push. Would anyone really argue this is meaningful to how a sneaker would wear if a person wore it - then it isn't scientific. Scientific just means you gain information, people were doing scientific research long before there were machines.
I think that anyone willing to cough up around $100,000 US dollars, give or take, would be able to procure said machine.
Do you really think it is impossible for a user or knife maker to develop and refine his knives without such a machine? To be frank, if the difference in performance is so small that it takes extreme measures to see it then it is obviously of no consequence to the user or maker because they will never notice it in use.
Another problem not mentioned, is that manilla hemp rope is highly variable with regards to abrasiveness and consistency from batch to batch. Until a rope can be obtained that is made specifically for cutting, I am afraid that these variables could possibly skew test results.
Use more than one sample, there is always going to be sample variance. Ideally you just want it at a level so that it doesn't dominate the measurements. You have to do a number of trials anyway. Ideally you would repeat it on different blades from different steel batches and different heat treat batches to see the total spread of performance.
Sal Glesser said:
... it's a "competition", not just a test.
No arguement, though you can bet that it is going to turn into a huge promotion pushing knives and especially steel if the right person wins. It would be more impressive to me to see makers enter with inexpensive carbon and low alloy tool steels. Do you really need 3V to cut a 2x4 when Kevin Cashen has said you can do that with mild steel and still shave? I see it as similar to the STIHL series competitions. These are *not* used to promote the axes as actually working tools, they are actually cast stainless and they break readily on anything other than clear wood, they are used to showcase the extreme skill of the individuals. What I would personally like to see is a competition which was more like this :
First event - sod cutting:
-You have to remove a 4x4 patch of sod in one foot wide strips which is going to be used to form the roof of a shelter. You also have provided a one foot section of 2x4 so you can either use the 2x4 to make a tool or just cut it with the knife. The winner gets a score of 100 and the rest are scaled with time. You get zero if the sod strips are not self supporting.
Second event - fire making :
-You are given a four foot length of 4x4 and a ferro rod and have to bring one litre of water to a boil. The scores are again scaled in time.
Third event - steel cut :
-You are given a 4x4 piece of mild steel nailed to a frame, you have to cut a 2x2 hole in the middle. You have a 26 oz framing hammer and a one foot length of 2x4 available for batons. Score is scaled with time.
Forth event - turkey cut :
-You are given a large turkey. You have to reduce it to form for stock. All the fat is trimmed, and wing tips removed, leg/wing joints separated, breasts and tenders removed. The score is again ranked in time. The cuts are also judged for acceptance and you fail if they are below tolerance (joints not cut in the right place so the marrow is visible, the tendors or breasts are torn, etc.).
Fifth event - "arrow" removal :
-A 6" spike is nailed half way into a piece of 6x6, remove it by any means necessary. The score is scaled again with time.
Sixth event - rope cutting
-Cuts are made through one inch hemp rope on both a push and a pull (two inch draw) on a scale. Five cuts are made evenly from the choil to tip, the maximum force is recorded each time. The scores are ranked by the force applied. You get zero if you fail to make a cut on any attempt.
And finally - sharpening :
-A standard benchstone is provided throughout the event. The time spent sharpening is recorded and the scaled time is used as the score. This is 50% of the total score and the other 50% comes from the score of the other events. The order of the events are random and will change from one competiton to the other. The specific events are not critical, the general idea is just to give a very wide range of tasks and make it impossible for a knife to actually be optomized for all of them and include work commonly done by tactical/survival knives as well as bushcraft/hunting knives.
As well give the user the ability to vary technique to suit the knife. The knife for example in the sod cutting can go through the sods way faster than using the wood, however on a brittle steel the edge can chip or fracture badly and thus really cost time in sharpening, especially if the grindability is low. Similar for the hammer vs wood baton. A really tough knife will take the heavy hammer hits and chew through the metal but a brittle knife has to rely on the wooden baton and go much slower. Same for the fire starting and nail removal, a very strong knife can be used much more aggressively and will take apart the wood much faster.
-Cliff
