- Joined
- Oct 24, 2002
- Messages
- 59
I have read some recent knife tests and reviews here that have left me fascinated with the results. However, the subsequent follow-up posts hint at a certain dissatisfaction with the methodology employed by the tester(s). Well, Marty and I have always been sticklers for scientific accuracy when conducting our own knife tests, so I thought Id offer an example of our testing procedures, including some of the results.
First, you can never do the same test twice. Repeatability is a myth. For example, just the other day, Marty set out to demonstrate his new Bark River prototypes out-of-the-box sharpness. For his test medium he chose an old rug someone had left on a clothes line in their back yard.. Well, Marty didnt choose it actually, I kind of told him no one would leave a good rug hanging outside like that so it must be trash waiting for pick-up day, and that we should save them the trouble of hauling it off by taking it ourselves for the knife test. Marty wasnt sure, but I grabbed the rug and the two of us ran back to my garage like two kids who just stole a watermelon from the neighbors garden. Actually, it was exactly like that since Marty grabbed a watermelon from their garden before we scampered off.
Anyway, after we butchered the melon with Martys new knife and ate so much all we could do was lay around on the garage floor and moan, we decided to postpone the rug cutting until later. I might interject here that scientific experiments should not be forced. The experimenter should be in the proper state of mind, and not be hopping from one foot to another because they ate half a watermelon and have to take a wicked leak.
Later that day we proceeded with the sharpness test. The rug appeared to have been recently cleaned, so sand and dirt inclusions could be excluded as possible variables in the experiment. (More about variables later.) We positioned the rug atop my plywood workbench, carefully inserting a layer of new carpet matting between the rug and the workbench top. This is called a control. I wanted to test the blades edge retention against the rug, not the benchs plywood. The matting would hopefully prevent the knife from reaching the wood and isolate the cutting to the rug and the underlying mat. The rug appeared to be made of some natural material, perhaps wool of some kind, but the deep colored dye and intricate patterns of the weave made it impossible for me to be certain. Marty seemed to think it was wool too, and he asked me, Kliff, are sure this is trash? It looks in pretty good shape to me.
Nonsense, I replied. Who leaves rugs hanging outside like that?
Well, Prudence for one, Marty said, referring to his wife and one of my greatest detractors when it comes to my knife testing activities.
Of course Prudence would do that. I scoffed. That hardly proves a thing. Marty nodded, unable to refute my keen scientific logic.
Starting at one end of the rug, Marty cleanly sliced it along the near edge completely removing the frilly part on that side. I examined the cut. It was neat and even. I then took the knife from Marty and started to test the edge by shaving some hair off of Martys arm. Marty protested, Hey, shave your own arm. The last time you did that it took four stitches to close the wound.
I would, I answered. But you tested initial sharpness on your arm and now that is the control. If we use my arm it would introduce a variable to the experiment.
Marty took one look at his relatively lightly haired arm and my rather hirsute appendage and reluctantly agreed. I see what you mean, you hairy ape, but give me that dang knife, Ill do my own shaving thank you.
Marty took the knife, started to shave his arm, and promptly cut himself near the wrist.
Wow, I said, that will take about four stitches to close.
Marty shot me a dirty look and said, Shut up and grab that medical kit behind you.
After we returned from the emergency room, we went back to cutting up the rug, only this time I wielded the knife. After slicing several more strips off the rug and testing the edge against my forearm hair we quickly developed a theory about the knife and the test material. The edge was simply too sharp and strong for the rug. Repeated cuts on the bench had not reduced edge sharpness to any noticeable degree so we decided to change the test parameters by hanging the rug from the top of one of my shelving units.
While changing test procedures in the middle of a test is usually frowned upon by the wider scientific community, this is often done during knife tests for no discernable reason and is widely accepted by knife testers and those reading knife test reviews. If you doubt me, just read a few of the test reviews posted here.
Anyway, with the rug now repositioned I decided to do a few slash tests to see if the Bark Rivers sharpness was keen enough to slice through free hanging material. It was. Unfortunately, in our haste to hang the rug we had failed to check the contents of the shelves behind it. As the knife sailed through the rug the point contacted and penetrated a can of spray paint sitting on the shelf. When Marty and I heard the hissing sound that ensued, we yanked the rug down to see what it was. In scientific parlance this is called results verification. It is also called unintended consequences since when we removed the rug the can of spray paint covered both Marty and I with a good coating of Forest Green enamel before it jetted off the shelf and began rolling around my garage spray painting everything as it spun wildly about.
By the time I managed to grab the can and throw it in the trash, Marty and I, the rug, the knife, and most of my garage had been refinished in a nice earth tone green. Good thing I like that color. Well, Marty and I decided the test had reached its conclusion and we could learn nothing more from additional work with the knife and rug. The sun had set outside, so I decided to take the rug back to where we had found it. After all, it had been left out as trash anyway, so we hung it back up on the clothes line and scurried back to my house under cover of the night. Once back in the garage we popped a couple of beers and began to discuss the outcome of our latest knife test.
Oh, I almost forgot, I wanted to add something about variables. One thing about variables - you want to eliminate them. One very important variable to exclude during knife tests is wives. Most lack the proper scientific attitude, and some can be downright skeptical when it comes to knife test results. For example, Marty and I had been sitting in the garage for about an hour when my wife Bunny decided to visit the garage to see what was going on. In doing so she introduced an undesirable variable.
Kliff, you wont believe what happened today, She said as she came through the door. As soon as her eyes adjusted to the garages dim light she saw the mess created by the punctured spray paint can. Oh, my God, Kliff, dont tell me it was you.
I looked at Marty and then at my wife, a perplexed expression hiding the terror just beneath the surface of my face. Why, Honey, what are you talking about?
Dont you 'Honey' me, Kliff. I just got off the phone with Joyce down the street. She was in tears. Apparently someone stole her extremely expensive Persian rug from her backyard. Then for some inexplicable reason the vandals shredded it before returning what was left to where they had taken it from in the first place.
Oh, I grunted and looked at Marty. Thats terrible. Did Joyce say anything else? I asked, smiling innocently, my white teeth clearly set off by the dark green paint covering most of my face.
Yes, Kliff, she did. Bunny nodded her head. She said the sickos not only cut up her rug, but they painted it green too.
Knife experimenters need to be an intrepid lot. They need to learn from the results of past experiments, so from experience I instinctively ran when my wife picked up the nearest thing she could grab from my workbench a hammer. Unfortunately Marty had not seen Bunny in this situation before and he failed to exercise his escape clause. He wont do that again.
So we learned a lot from our test, but as I said before, like all of my tests, none of this one is repeatable. Youll just have to take my word for it.
First, you can never do the same test twice. Repeatability is a myth. For example, just the other day, Marty set out to demonstrate his new Bark River prototypes out-of-the-box sharpness. For his test medium he chose an old rug someone had left on a clothes line in their back yard.. Well, Marty didnt choose it actually, I kind of told him no one would leave a good rug hanging outside like that so it must be trash waiting for pick-up day, and that we should save them the trouble of hauling it off by taking it ourselves for the knife test. Marty wasnt sure, but I grabbed the rug and the two of us ran back to my garage like two kids who just stole a watermelon from the neighbors garden. Actually, it was exactly like that since Marty grabbed a watermelon from their garden before we scampered off.
Anyway, after we butchered the melon with Martys new knife and ate so much all we could do was lay around on the garage floor and moan, we decided to postpone the rug cutting until later. I might interject here that scientific experiments should not be forced. The experimenter should be in the proper state of mind, and not be hopping from one foot to another because they ate half a watermelon and have to take a wicked leak.
Later that day we proceeded with the sharpness test. The rug appeared to have been recently cleaned, so sand and dirt inclusions could be excluded as possible variables in the experiment. (More about variables later.) We positioned the rug atop my plywood workbench, carefully inserting a layer of new carpet matting between the rug and the workbench top. This is called a control. I wanted to test the blades edge retention against the rug, not the benchs plywood. The matting would hopefully prevent the knife from reaching the wood and isolate the cutting to the rug and the underlying mat. The rug appeared to be made of some natural material, perhaps wool of some kind, but the deep colored dye and intricate patterns of the weave made it impossible for me to be certain. Marty seemed to think it was wool too, and he asked me, Kliff, are sure this is trash? It looks in pretty good shape to me.
Nonsense, I replied. Who leaves rugs hanging outside like that?
Well, Prudence for one, Marty said, referring to his wife and one of my greatest detractors when it comes to my knife testing activities.
Of course Prudence would do that. I scoffed. That hardly proves a thing. Marty nodded, unable to refute my keen scientific logic.
Starting at one end of the rug, Marty cleanly sliced it along the near edge completely removing the frilly part on that side. I examined the cut. It was neat and even. I then took the knife from Marty and started to test the edge by shaving some hair off of Martys arm. Marty protested, Hey, shave your own arm. The last time you did that it took four stitches to close the wound.
I would, I answered. But you tested initial sharpness on your arm and now that is the control. If we use my arm it would introduce a variable to the experiment.
Marty took one look at his relatively lightly haired arm and my rather hirsute appendage and reluctantly agreed. I see what you mean, you hairy ape, but give me that dang knife, Ill do my own shaving thank you.
Marty took the knife, started to shave his arm, and promptly cut himself near the wrist.
Wow, I said, that will take about four stitches to close.
Marty shot me a dirty look and said, Shut up and grab that medical kit behind you.
After we returned from the emergency room, we went back to cutting up the rug, only this time I wielded the knife. After slicing several more strips off the rug and testing the edge against my forearm hair we quickly developed a theory about the knife and the test material. The edge was simply too sharp and strong for the rug. Repeated cuts on the bench had not reduced edge sharpness to any noticeable degree so we decided to change the test parameters by hanging the rug from the top of one of my shelving units.
While changing test procedures in the middle of a test is usually frowned upon by the wider scientific community, this is often done during knife tests for no discernable reason and is widely accepted by knife testers and those reading knife test reviews. If you doubt me, just read a few of the test reviews posted here.
Anyway, with the rug now repositioned I decided to do a few slash tests to see if the Bark Rivers sharpness was keen enough to slice through free hanging material. It was. Unfortunately, in our haste to hang the rug we had failed to check the contents of the shelves behind it. As the knife sailed through the rug the point contacted and penetrated a can of spray paint sitting on the shelf. When Marty and I heard the hissing sound that ensued, we yanked the rug down to see what it was. In scientific parlance this is called results verification. It is also called unintended consequences since when we removed the rug the can of spray paint covered both Marty and I with a good coating of Forest Green enamel before it jetted off the shelf and began rolling around my garage spray painting everything as it spun wildly about.
By the time I managed to grab the can and throw it in the trash, Marty and I, the rug, the knife, and most of my garage had been refinished in a nice earth tone green. Good thing I like that color. Well, Marty and I decided the test had reached its conclusion and we could learn nothing more from additional work with the knife and rug. The sun had set outside, so I decided to take the rug back to where we had found it. After all, it had been left out as trash anyway, so we hung it back up on the clothes line and scurried back to my house under cover of the night. Once back in the garage we popped a couple of beers and began to discuss the outcome of our latest knife test.
Oh, I almost forgot, I wanted to add something about variables. One thing about variables - you want to eliminate them. One very important variable to exclude during knife tests is wives. Most lack the proper scientific attitude, and some can be downright skeptical when it comes to knife test results. For example, Marty and I had been sitting in the garage for about an hour when my wife Bunny decided to visit the garage to see what was going on. In doing so she introduced an undesirable variable.
Kliff, you wont believe what happened today, She said as she came through the door. As soon as her eyes adjusted to the garages dim light she saw the mess created by the punctured spray paint can. Oh, my God, Kliff, dont tell me it was you.
I looked at Marty and then at my wife, a perplexed expression hiding the terror just beneath the surface of my face. Why, Honey, what are you talking about?
Dont you 'Honey' me, Kliff. I just got off the phone with Joyce down the street. She was in tears. Apparently someone stole her extremely expensive Persian rug from her backyard. Then for some inexplicable reason the vandals shredded it before returning what was left to where they had taken it from in the first place.
Oh, I grunted and looked at Marty. Thats terrible. Did Joyce say anything else? I asked, smiling innocently, my white teeth clearly set off by the dark green paint covering most of my face.
Yes, Kliff, she did. Bunny nodded her head. She said the sickos not only cut up her rug, but they painted it green too.
Knife experimenters need to be an intrepid lot. They need to learn from the results of past experiments, so from experience I instinctively ran when my wife picked up the nearest thing she could grab from my workbench a hammer. Unfortunately Marty had not seen Bunny in this situation before and he failed to exercise his escape clause. He wont do that again.
So we learned a lot from our test, but as I said before, like all of my tests, none of this one is repeatable. Youll just have to take my word for it.
By the tone of your review I can tell you probably hold some kind of degree in a scientific field 
