Extreme testing of one of my D2 knives (with pics)

[knifetester]

I am of the belief that makers should test their products to failure (in various modes) as a part of research and development and for quality control. Obviously it does not have to be a hand rubbed satin finsh piece with exhibition grade koa wood on the handle. Just a ground blank (bevels and edge formed) to check HT, Steel consistency, etc.

How can a maker tell his customers what the full scope of work of a knife is i.e. how hard it can be safely used before different modes of failure occur if he does not know himself?

IN the production realm, I think Swamp Rat and Fallkniven are the only companies to have so, and Sal Glesser is very frank about the lock strength on his folders.

Look at the insane number of blades Nick Wheeler breaks, and then look at his heat treat and quality control. The benefit is very clear.

A lot of makers do not have the confidence to publish their results.

I congratulate Scott for doing so.

When I do a convex grind it's slack belt grinding from the beginning. I've heard of flat grinding to a point then switch to slack belt. I do total slack belt so my blades have more meat along the center line.

Scott,
Does leaving more steel along the center line (a true convex knife) ake the edge itself more durable? If so, is this a function of geometry, increaed cross section or both?

 

[Gossman Knives]

Scott,
Does leaving more steel along the center line (a true convex knife) ake the edge itself more durable? If so, is this a function of geometry, increaed cross section or both?

Yes in my experience it does make the edge more durable.......but it has to be an almost zero edge. In other words, little to no secondary bevel. I do have a very slight secondary bevel on most of my knives. I have done some to zero edge but I prefer a slight secondary bevel. The nice thing about my convex grinds is stropping is all that's necessary to maintain them. A charged leather belt is what I use to resharpen. Sometimes I do it on my 2x48 grinder if in the case of the test knife, but not very often ( it's to the right of my 2x72 grinder). Last deer season, I maintained my knife simply by stropping and I use it for everthing while hunting, not just game work. Here's a pic of my slack belt set up. To the left on the bench is a large vise clamp holding down my strop. That big white chunk is 600 grit alumium oxide to charge the belt. That's what I use. Real cheap sharpening method.

Scott

 

[stropper]

Scott,

I would never call you a hypocrite and didn’t set out to do so in my first post.

Not to brownnose but to put my post in the right perspective: I have always liked your no-nonsense, sturdy, working designs. (Damn,... still sounds a lot like brownnosing!)

You simply changed your mind and now you believe you CAN get valuable information from this kind of extreme tests. I applaud you!!

Let me quote you again: “as a maker this type of testing was necessary for my own satisfaction”
That one makes me forget those other quotes real quick!

Like Knifetester, I can’t understand why not every knifemaker has that attitude.
Especialy with all those reports on the performance of D2 contradicting each other, how can a knifemaker NOT want to see for himself.

Again: Respect!!!
(also: we want more!!)

 

[Gossman Knives]

Thank you for the kind words. I was originally going to put together a 5160 camp knife and take a city block down. Seriously, I started thinking about all the controversy about D2 and thought, well I've got this test piece waiting to be tested and it's D2 so why not give it a whirl. I now feel confident enough about D2 that I feel it would work well in a 7 to 8 inch blade size knife.
Scott

 

[JD Mandrell]

I agree with knifetester, it's great to see an actual knife maker testing his products and being willing to post the results. As the man who actually made the knife, who better to test and evaluate it's performance. The tests Scott did here more than prove his D2 knives (and I have no doubt his others would as well) can handle any normal and even above normal use if needed.

His knives are so good, my knife collection is threatening to divorce me cause I only carry my Razorbacks! yuk yuk

 

[Gossman Knives]

I agree with knifetester, it's great to see an actual knife maker testing his products and being willing to post the results. As the man who actually made the knife, who better to test and evaluate it's performance. The tests Scott did here more than prove his D2 knives (and I have no doubt his others would as well) can handle any normal and even above normal use if needed.

His knives are so good, my knife collection is threatening to divorce me cause I only carry my Razorbacks! yuk yuk

Stop you're making me blush. I'm forever second guessing my work. Going back and forth, checking, double checking everything but still strive for improvement. At times I'm my own worst critic, which I guess is good. I will never be completely satisfied, that's the only way to get better. I'm so glad to have done this testing because it keep's the confidence level up for doing even better the next time.
Scott

 

[Gossman Knives]

I was playing back in head when I did the nail cut and was trying figure out why the edge chipped. I think when I hit the back of the blade during the series of hits, I may have made the blade kant right or left when the hammer struck the spine. This as Cliff said, would cause the area of the edge in contact with the nail to chip. I'm not sure if this happen but it's a good possibilty. Reason being is that after the chip I moved up the blade to finish cutting the nail in half with no chipping. I didn't keep count of the number of hammer blows, I'm guessing six.
Scott

 

[sodak]

This is difficult... I had a nice firm opinion that D2 made a great small knife steel when properly hardened (I still think that, got some little cutters that seem to hold an edge forever). Now I have to reconsider it for a larger blade... Hmmm...

 

[Cliff Stamp]

Cliff, how does this performance compare to your Dozier you tested with D2 but w/o a convex grind?

I took the Dozier Agent and stabbed it into a concrete block 12 times. There was no effect on the tip aside from some impaction. The edge took a large chip when it smacked a fairly large rock in the concrete. The edge broke away up to 0.015" thick. The stabs were as hard as possible, full shoulder swings, the knife is so light though that the impact energy is much smaller than with a larger knife, but still :

http://i7.photobucket.com/albums/y269/CliffStamp/dozier/agent_block_stab.jpg

http://i7.photobucket.com/albums/y269/CliffStamp/dozier/agent_block_stab_horizontal.jpg

Note the blade was actually getting stuck into the block, the second picture shows the knife staying in the block turned on its side. First time I have seen that which was interesting. The tip was thick enough to prevent bending, but thin enough to get good penetration, about 1/4" on each stab. I had to reset my grip after each couple of stabs, little to no guard, and a slick grip.

The Agent was then chopped into the side of the block fifty times, the first were light impacts, just wrist, and the second were full effort from the shoulder. The edge actually chipped the same in both cases as the light ones whacked into a couple of large rocks and the heavy ones cut mainly the cement. The damage was up to 0.020" thick in both cases, note the edge here is very acute about 10 degrees per side. A shot :

http://i7.photobucket.com/albums/y269/CliffStamp/dozier/agent_block_work.jpg

The edge was then reground to 22 degrees per side (five passes per side on a worn 100 grit AO belt) removing all the damage and leaving a shaving sharp edge, about 30 s. The chopping was repeated with heavy swings and no significant depth of chipping was evident, the edge was just blunted. The knife is just too light to impact with any energy.

-Cliff

 

[Danbo]

I'm sure I'm not the only one thinking this, but WHY?

 

[Cliff Stamp]

I'm sure I'm not the only one thinking this, but WHY?

That was pretty clear :

I was merely employing some extreme conditions that may be encountered in the wilderness. The possibility of hitting rock and metal in the wild is very real.

Small knives can generally take heavy use of this type without major damage as they are too light to impact with any real energy, the only real concerns are heavy tip tapers, or extreme hollow ground edges.

As an interesting aside, I did this awhile ago with the CU/7 from Becker, it took similar damage to the Agent, the steel is tougher, but the blade is way heavier so it impacts with much more energy.

-Cliff

 

[Gossman Knives]

Let me clarify something to everyone about why I did this extreme testing. As alot of people already know I've butted heads with Cliff about his testing methods in the past. He has his reasoning for doing what he does even though I don't always agree. Anyone who wants to do this type of testing can do it but it's the makers or manufactuers responsibility to do it so that the buyer doesn't have to. I'm making a product, I'm testing my product to see if it will perform. What I meant in the other post is I shouldn't have to do this with my Randall 25. It's Randalls responsibility to do this themselves. That way I know that the Randall I paid alot of money for will will perform if I run up against an "unusal" situation. If you are in the woods chopping poles for a shelter and miss your mark and hit a rock, how will the knife handle that? This is what this testing for me, was all about. I hope that sheds a little light on why I did this.
Scott

 

[knifetester]

What I meant in the other post is I shouldn't have to do this with my Randall 25. It's Randalls responsibility to do this themselves. That way I know that the Randall I paid alot of money for will will perform if I run up against an "unusal" situation. If you are in the woods chopping poles for a shelter and miss your mark and hit a rock, how will the knife handle that? This is what this testing for me, was all about

Exactly correct imho.

 

[Cliff Stamp]

...it's the makers or manufactuers responsibility to do it so that the buyer doesn't have to.

It is the makers responsibility to do it so he can make a better product. It is the users responsiblity to do it to keep them honest. Let us be frank, not everyone in the industry makes knives that can stand up to their promotion.

Ask a simple question "If I do the same things you have done, do you guarantee the results you describe?". If the answer is no, then disregard any and all claims made as they are meaningless promotional hype.

To clarify, as this is constantly misunderstood/misrepresented, this doesn't mean you can take a knife, simply test it to destruction and then ask for a replacement irregardless of how it performs.

What it means is that you should be able to try the tests out for yourself and if the performance is significantly lower than promoted you are within your rights to demand a replacement as either the product is defective or it was being overhyped.

-Cliff

 

[Gossman Knives]

It is the makers responsibility to do it so he can make a better product. It is the users responsiblity to do it to keep them honest. Let us be frank, not everyone in the industry makes knives that can stand up to their promotion.

Ask a simple question "If I do the same things you have done, do you guarantee the results you describe?". If the answer is no, then disregard any and all claims made as they are meaningless promotional hype.

To clarify, as this is constantly misunderstood/misrepresented, this doesn't mean you can take a knife, simply test it to destruction and then ask for a replacement irregardless of how it performs.

What it means is that you should be able to try the tests out for yourself and if the performance is significantly lower than promoted you are within your rights to demand a replacement as either the product is defective or it was being overhyped.

-Cliff

Cliff, I was hoping not to debate you on this. I disagree with what you are saying. Reason being,
#1 What I did is considered in manufacturing as quaility control. All reputable knife companies and or makers I'm assuming do it.
#2 What I did would be considered deliberate abuse of the knife. This has been said before, knives are not made to chop cinder blocks or cut nails. There are other tools designed for these things. Mauls are for breaking concrete and bolt cutters or cut off wheels are for cutting nails.
#3 If you ask any maker or knife company if they warrant this type of use as I did in this test, I seriously doubt they would cover it. They would call it abuse and not normal use of a knife.
Here's another example, automobile manufacturers crash test their cars and trucks to be sure they pass certain safety requirements. Say you knew exactly the tests they performed. You bought a vehicle as a consumer, you drove off the car lot, went down the street and deliberately crashed it into a brick wall and was injured because the vehicle didn't perform the way it did in the tests, do you think you would get your money back? It would be a different story if it was an unintential accident. Cliff, I'm not trying to argue with you, I'm just trying to get you to see my point of view. It would be nice to do a poll of makers and knife manufacturers to see if they would replace a knife that was deliberately abused. I understand that you are given knives by certain people to abuse to the breaking point, I guess you are their quaility control engineer. If you are being asked to do the things you do then I can see why you do them.
Scott

 

[knifetester]

If a certain use, say Lynn Thompson stabbing a tanto though a 50 gal drum, is the promoted use of a knife, can it be considered abuse when the consumer does the same?

What constitutes abuse surely must differ from knife to knife. Cutting through a pressure cooked bone to extract marrow might be abusive in regards to a Johnson full hard 1095 paring knife, but a 3V Ferman should be unphased by such use.

Part of what constitutes abuse must be reasonableness, or lack thereof.

While I am not a lawyer, I having a passing familiarity with law concerning the sale of goods, which in the U.S. is covered by each States version of the Uniform Commercial Code (UCC) which is very similiar, and thus uniform, from state to state.

In international sales, signatory nations of certain treaties must follow fairly similiar rules, though with some differences concerning risk of loss and such.

The sale of a knife is by any measure the sale of goods, and therefore the UCC applies.

One provision of Article 2 of the UCC covers Warranties, most importantly, express warranties and implied at law. Disclaimers are also covered.

When a makers, who who qualify as a merchant as dealing in goods of that type, i.e. knife he made, says or shows that a knife will do something, and it fails doing it, there has been a breach of an express warranty. So, if Lynn Thompson shows his knife puching through steel cans without damage, and this is "material" to the bargain (part of what induces a customer to buy a knife) then it is an express warranty that it will do this, and if it fails their is a breach. This breach is regardless of fault, warranty theory is akin to strict liablity.

Certain unforseen uses, i.e. abuse, can invalidate a warranty claim. For example intentionally running a car into a brick wall where there has been no claim it could withstand such use.

Implied at law include merchantablity (the produdcut is of fair average quality for the intended use of such products) and paticular purpose. If I tell a maker maker I am planning on using a knife as a rock climbing pitton, and he sells me one that in his opinion does, and I rely on his opinion in choosing that model, he is liable if it fails.

So, what is a warranty, what is considered abuse, and what the rights of the perspective partioes are is really as much a matter of law than anything.

Again, I am not a lawyer and I am not giving legal advise, just a quick and perhaps overly simplistic view that the issue being discussed is more complex than originally contemplated, but that in our society of laws, there is a framework for resolving such disputes.

 

[knifetester]

It is the users responsiblity to do it to keep them honest.

I disagree that the user has any such responsibily, at least in terms of an affirmative duty. In the abstract sense, a free market does accomplish this, if buyers choose not to buy products that fail of their essential purpose, fail to live up to claims or are not adequately supported by the maker.

 

[Cliff Stamp]

I disagree that the user has any such responsibily...

This is pretty much a personal choice, I feel that you as an individual have to do your part. Of course not everyone can afford to crash test a car, but I think you can expect simple locks tests for strength/security and not just blindly rely on what the makers say. Even if they were 100% honest and never overhyped their products, the user should still do a few checks just to try and catch flaws the makers can't, outside of high end customs, you can't expect individual testing from the makers.

If a certain use, say Lynn Thompson stabbing a tanto though a 50 gal drum, is the promoted use of a knife, can it be considered abuse when the consumer does the same?

There is a huge bias in the industry concerning maker vs user in many respects, what they can do with their knives is one. This thread is an obvious example in many ways. Lets assume that before Razorback posted this thread I had bought one of his knives and did the exact same thing and posted up the results. Do you really think the commentary would have went the same way? Of course not.

What constitutes abuse surely must differ from knife to knife.

Abuse is just using the knife for a task it was not designed and promoted to do and thus results in functionally damaging the knife.

When a makers, who who qualify as a merchant as dealing in goods of that type, i.e. knife he made, says or shows that a knife will do something, and it fails doing it, there has been a breach of an express warranty.

Outside of a legal debate, I would simply make a claim for reasonable behavior. If you are going to sell a product by promoting a certain standard of performance I think it is reasonable for the consumer to expect that level of performance.

Arguing otherwise just allows makers to make any insane claims of abilities with nothing to hold them in check. This of course is not limited to just banging a knife against a rock, but holds for edge retention and any and all other performance claims.

[QC]

All reputable knife companies and or makers I'm assuming do it.

That is a circular defination.

What I did would be considered deliberate abuse of the knife.

If I cut enough cardboard it would remove the same amount of material through wear and sharpening, you described no significant damage.

Why would you be concerned if someone else duplicated it - don't you have faith in your consistency and that they would get the same results?

This has been said before, knives are not made to chop cinder blocks or cut nails.

There are knives designed to function as entry tools and be able to withstand severe prying and edge contacts. This isn't material to the discussion at hand though, which is a maker's responsibilty for their knives to perform as promoted. You decide what uses to promote of course.

If you ask any maker or knife company if they warrant this type of use as I did in this test, I seriously doubt they would cover it.

Lots of makers will guarantee their knives will perform as they describe. Of course what they promote is critical.

...as a consumer, you drove off the car lot, went down the street and deliberately crashed it into a brick wall and was injured because the vehicle didn't perform the way it did in the tests, do you think you would get your money back?

No, you would likely get a lot more. If you were injured, and it was clear it was because of a defect you would have lawyers on stampede to your door. It doesn't matter why you do it, the product failed.

I guess you are their quaility control engineer.

No they have people who do that, there are fairly obvious reasons why people get independent user feedback.

-Cliff

 

[Gossman Knives]

Thanks Cliff.
Scott

 

[JD Mandrell]

Quote:
...as a consumer, you drove off the car lot, went down the street and deliberately crashed it into a brick wall and was injured because the vehicle didn't perform the way it did in the tests, do you think you would get your money back?

No, you would likely get a lot more. If you were injured, and it was clear it was because of a defect you would have lawyers on stampede to your door. It doesn't matter why you do it, the product failed.

Not hardly, if you DELIBERATELY drove the car into a wall, you are not going to collect anything.

There was no accident, it was a deliberate criminal act.