Knife blades penetrating car doors: Reasonable Strength Test or Not?

[Comeuppance]

Roughly how long does the AUS-8A blade last compared to the S30V one, just roughly as in half day vs a day ...

In my experience, S30V outclasses AUS8 by about 4x the wear resistance, and is much more corrosion resistant. I was sharpening and cleaning off rust spots daily with my Counter Point 2 and Large Voyager. With S30V, I've sharpened my Manix2 XL (which sees the most use) about three times in four months. Now, it's worth noting this huge disparity is partially due to the poor edge geometry of the CP2 and the tasks I would set the voyager upon, but for fine cutting and day-to-day use, S30V has proved magnitudes better. AUS8 seemed to lose a fine edge faster than some of the mystery stainless knives I've had in the past, whereas S30V retains hair-poppability well after breaking down several cardboard boxes.

Also, I've yet to have a solitary stain on my Manix's blade, and all I do is wipe it off with a paper towel. My AUS8 knives, even the stonewashed Voyager, developed spots (and sometimes orange spots) after just 8 hours in my pocket in a relatively dry climate.

There are more standardized tests than mine, and it will, of course, be slightly skewed by my tendency to baby my Manix XL, but there is a definite and noticeable difference in edge retention and ease of attaining a fine edge. S30V dulls so slowly that I can restore it to a factory edge with just a stone and a few minutes, whereas AUS8 rounds, bends, and folds readily. AUS8 isn't going to chip on me, but it also won't do all of my daily tasks and then trim my fingernails.

[bdblue]

a well-known knife company that manufactures very good quality blades is known to use their knives to pierce the steel of car doors, to show how strong and sharp and resilient they are. I'm asking all of you fellow knife enthusiasts here: Is this test a true measure of how good a knife is, or not?

I like that products from that company but I would not put very many of them equal to the better Spyderco knives.

There is not any one test to measure how good a knife is. I don't think you can even write a definition of what a good knife is, this means different things to different people. Stabbing a car door shows how strong the point is and might be an interesting test to someone that needs a strong point, and BTW I wouldn't recommend trying this with a Military or PM2. But most people use their knives for different things and don't care about stabbing car doors. Another test I saw was chopping a hole through a wood 2x4 by stabbing the point in and then moving the knife sideways to pull out chunks of wood. This test seemed to be a good test of point strength, and I would not expect very many real cheap knives to survive this test.

I read a story about someone that escaped from a burning building by cutting through a metal door with their knife so in that case a strong point was important. I read another story about someone that was in a van that fell in a river and they escaped by cutting a hole in the roof. Again this is a time when a strong point came in handy. I read a story on another forum just today of a police officer on duty that had to pry up a street drainage grate with his folding knife. nives are not designed for this and this is not recommended behavior but if an officer needs to do this and his knife is his best tool to do it with, then it would be good if his knife could perform the task for him and survive it. People that bushcraft need different qualities compared to people that hunt or people that carry a knife in an office or carry a knife in a construction environment or carry a knife in a warehouse. So different tests would be relevant for each of these different groups of people.

I find it interesting that no other manufacturer does these types of tests to their knives. I also find it interesting that in some of the destruction tests I've watched on youtube, very expensive knives have failed those tests early in the testing.

I don't have much need to punch through car doors or 2x4's, or whatever, but I like to know the limits of a knife and how it might work in whatever daily use I have. And if I need to do something with a knife other than slice a banana I want to know that it won't break immediately.

[Blerv]

In my experience, S30V outclasses AUS8 by about 4x the wear resistance, and is much more corrosion resistant. I was sharpening and cleaning off rust spots daily with my Counter Point 2 and Large Voyager. With S30V, I've sharpened my Manix2 XL (which sees the most use) about three times in four months.

You are comparing two much different knives though (grinds). Different brands even (possible HT).

I don't doubt in many cases AUS8 will be surpassed by S30v. 4 times though is a huge difference. Also, my science is rough but AUS8 has a tiny bit more chromium and about half the carbon which would assume it would be somewhat more corrosion resistant instead of less. That isn't to say you don't have something happening there, it just seems there might be other factors at play.

Ill let the smarter people comment further :) .

Back to the topic...I still believe stabbing car hoods is an unsubstantiated test of strength or quality. Perhaps splitting a bullet or slashing hanging beef would change my mind though.

[Comeuppance]

You are comparing two much different knives though (grinds). Different brands even (possible HT).

I don't doubt in many cases AUS8 will be surpassed by S30v. 4 times though is a huge difference. Also, my science is rough but AUS8 has more chromium an about half the carbon which would assume it would be drastically more corrosion resistant. That isn't to say you don't have something happening there, it just seems there might be other factors at play.

Ill let the smarter people comment further :) .

Yeah, like I said - skewed results, but it's my own personal experience. I suppose I'm primarily talking about fine edge retention, which AUS8 fails miserably at. There have been actual tests that, IIRC, show AUS8 to have roughly half of the edge retention of S30V... As far as fine edge retention goes, though, S30V seems to outclass AUS8 by a huge degree.

[tobii3]

Try shattering door window glass in a car with a knfe pimmel not specifically made for it. Let us know how long it takes.

Safety glass shatters at @100 PSI...Keep in mind the pommel of your knife is less than that one square inch. It takes MORE force to stab through the door.

Of course, simply putting the tip of the knife aainst the glass and hitting the pommel with the palm of your hand is just as effective.

Let me guess, me2, you've never broken the window, yet you have an opinion on what works and what doesn't?

I've broken the window with the antenna ball (older cars), my fist (not recommended), my elbow, a Motorola XTS5000 Radio, a brick, a rock and, of course, a knife. Now I've witnessed a fire extinguisher used, a crescent wrench, even a framing hammer...so what makes you so certain that a knife pommel that is "not specifically made for it" won't work?

[spyderHS08]

I think bdblue hit it spot on, great response.

It's great to know what your knife is capable of even if you don't plan to use it in that situation everyday but piece of mind in case of emergency is always good.

[chuck_roxas45]

I like that products from that company but I would not put very many of them equal to the better Spyderco knives.

There is not any one test to measure how good a knife is. I don't think you can even write a definition of what a good knife is, this means different things to different people. Stabbing a car door shows how strong the point is and might be an interesting test to someone that needs a strong point, and BTW I wouldn't recommend trying this with a Military or PM2. But most people use their knives for different things and don't care about stabbing car doors. Another test I saw was chopping a hole through a wood 2x4 by stabbing the point in and then moving the knife sideways to pull out chunks of wood. This test seemed to be a good test of point strength, and I would not expect very many real cheap knives to survive this test.

I read a story about someone that escaped from a burning building by cutting through a metal door with their knife so in that case a strong point was important. I read another story about someone that was in a van that fell in a river and they escaped by cutting a hole in the roof. Again this is a time when a strong point came in handy. I read a story on another forum just today of a police officer on duty that had to pry up a street drainage grate with his folding knife. nives are not designed for this and this is not recommended behavior but if an officer needs to do this and his knife is his best tool to do it with, then it would be good if his knife could perform the task for him and survive it. People that bushcraft need different qualities compared to people that hunt or people that carry a knife in an office or carry a knife in a construction environment or carry a knife in a warehouse. So different tests would be relevant for each of these different groups of people.

I find it interesting that no other manufacturer does these types of tests to their knives. I also find it interesting that in some of the destruction tests I've watched on youtube, very expensive knives have failed those tests early in the testing.

I don't have much need to punch through car doors or 2x4's, or whatever, but I like to know the limits of a knife and how it might work in whatever daily use I have. And if I need to do something with a knife other than slice a banana I want to know that it won't break immediately.

Well said brother, while I like some of my knives to be slicing demons,I also like some of my knives to have that capability(SHTF capabality), if only for one time use. Maybe that's why I'm called knuckle dragger. :D

[Evil D]

To me it's a better "test" of the pivot than anything else. Check out this video on the Wildsteer WX folder. He pounds it into a door with a mallet and then hammers a big slit with it and it's barely scratched. Now whether thats a reasonable test of strength or not it definitely speaks volumes about how strong that knife is at the pivot.

There's a bit of cursing going on so be warned.
http://www.youtube.com/watch?v=LOYlgsYh ... ata_player
Skip to about 12 minutes for the door part. I plan on ordering one of these soon just for the sake of abusing the crap out of it.

[The Mastiff]

The OP begins threads that are somewhat leading and easily can become controversial. Then he sits back to see what develops. There's something basically wrong with this. Please remember not to make statements that will embarrass Spyderco or give people who don't know us a wrong impression about this company or website.

The Lions and Tigers thread was an invitation to disaster. Fortunately no one took it serious and we had some laughs. I thought the OP was joking. Now I'm not sure what's the motive. Either a 14 year old kid or an agent provocateur. Either way I can't think of anything I'd have to discuss with him.

Sorry, Blunt and boorish as usual but that's me. :)

RRROOOOWWWWFFFFF!!@#$

Joe

[Cliff Stamp]

In my experience, S30V outclasses AUS8 by about 4x the wear resistance, and is much more corrosion resistant.

Are you measuring wear resistance somehow or inferring it from edge retention?

As Blerv noted, the differences in geometry and such far outweigh steel issues by orders of magnitude so unless they are fairly close that is what you will see dominate. Even if you find one knife more comfortable in hand or even simply you like it better that can easily dominate over the inherent steel performance.

...for fine cutting and day-to-day use, S30V has proved magnitudes better. AUS8 seemed to lose a fine edge faster than some of the mystery stainless knives I've had in the past, whereas S30V retains hair-poppability well after breaking down several cardboard boxes.

AUS-8 inherently has no disadvantage to S30V in regards to fine edge retention, as the large carbide volume of S30V can not help retain a fine edge as they are much larger than the edge. However in general S30V is used in more expensive knives and so you would expect better QC, tighter HT protocols, etc. .

However it seems to me to be a sharpening issue more than anything else, unless you have a number of defective AUS-8A knives as AUS-8A is in the same class as MBS-26, 19C27, etc. . The problem is that once you have a perception of performance it will become difficult to see otherwise.

You might want to see if you can find one of the older Benchmades in AUS-8A, they were among the highest regarded AUS-8A blades by guys who did a lot of steel comparisons and work (Joe Talmadge, etc. ).

[araneae]

The real test is can it penetrate a car door and kill a bear at the same time?

[SpyderEdgeForever]

To me it's a better "test" of the pivot than anything else. Check out this video on the Wildsteer WX folder. He pounds it into a door with a mallet and then hammers a big slit with it and it's barely scratched. Now whether thats a reasonable test of strength or not it definitely speaks volumes about how strong that knife is at the pivot.

There's a bit of cursing going on so be warned.
http://www.youtube.com/watch?v=LOYlgsYh ... ata_player
Skip to about 12 minutes for the door part. I plan on ordering one of these soon just for the sake of abusing the crap out of it.

Thanks for posting this. Those look to be some EXCELLENT knives!

[chuck_roxas45]

The OP begins threads that are somewhat leading and easily can become controversial. Then he sits back to see what develops. There's something basically wrong with this. Please remember not to make statements that will embarrass Spyderco or give people who don't know us a wrong impression about this company or website.

The Lions and Tigers thread was an invitation to disaster. Fortunately no one took it serious and we had some laughs. I thought the OP was joking. Now I'm not sure what's the motive. Either a 14 year old kid or an agent provocateur. Either way I can't think of anything I'd have to discuss with him.

Sorry, Blunt and boorish as usual but that's me. :)

RRROOOOWWWWFFFFF!!@#$

Joe

You are my kind of guy Joe. Less goody-goody and more straight talk is what we need these days. :D

[Blerv]

The real test is can it penetrate a car door and kill a bear at the same time?

Agreed. In the event bears learn to drive cars this is the only way to stop them.

[dbcad]

For the life of me I can't fathom a single good reason for putting a knife thru the metal of a car door :eek:

IMHO doing so would be much more an act of silly machismo rather than any kind of valid "test". It seems silly to try and test a knife for a task that is completely outside of it's design intentions and as well serves no useful purpose except to vandalize.

??????

[Auxiliaryjohn]

I can't help but cringe whenever I think of putting ANY of my knives through that. Yes I own a CS and have seen the videos of what was described and would never put any of mine through that just to prove a point. :eek:

[chuck_roxas45]

I can't help but cringe whenever I think of putting ANY of my knives through that. Yes I own a CS and have seen the videos of what was described and would never put any of mine through that just to prove a point. :eek:

That's precisely the point. We'd like "the other guys" to do it so we won't have to.

[me2]

I have not broken a car door window, but have watched the firefighters at the airport take 2 or 3 tries to break one with those odd looking pickaxe things they use for that. I cant imagine its easier to do with the pommel of a knife.

[Cliff Stamp]

For the life of me I can't fathom a single good reason for putting a knife thru the metal of a car door :eek:

The knives that were originally used for such work were emergency, survival, and as Strider always put it WAR knives, durability in extreme situations was one of the design constraints which is why Strider would stab the knives into the concrete floors, chop into table legs etc. at early shows. Lynn Thompson used the door panel / hood stabbing as a way to sell what he was promoting was the combination of penetration and strength of his "american tanto". Most people have no idea what it takes to poke a knife into a piece of sheet metal so they were very impressed thinking this was something difficult. Most marketing tests are like that because if you quoted actual materials statistics such as energy lost on a stab or deflection strength then it would not mean anything significant to most people.

While Thompson chose it purely because of the visuals, McClung went beyond it and demonstrated that he (and others) could use one of his knives to not only poke a few holes in a car, but could chop out a section of the roof if needed and in far greater time than general emergency response. Strider didn't make this exact claim, but again with the promotion of it being a WAR knife, cutting/stabbing and prying into metals isn't outside of the scope of work. It isn't like you need a knife which is 1/4" thick with a shallow sabre grind if all you are doing is cutting things as the knife clearly isn't designed to cut well.

It seems silly to try and test a knife for a task that is completely outside of it's design intentions and as well serves no useful purpose except to vandalize.

It isn't like knives are designed to cut silica impregnated paper, by subjected to acids etc., however these are all standard ways of measuring the performance of knives, Spyderco even does some of them (CATRA, Q-FOG, etc.). It is common to use extremes to predict more regular performance ranges, just ensuring you can make the necessary correlation.

The fact that a significant amount of people here actually believe that it is significant shows that Lynn Thompson, Strider, and Kevin Mcclung (the three top car cutters) picked a fairly solid test because the people here are in general more informed than the general public who would be even more inclined to think that it was an impressive feat.

[angusW]

If I'm not mistaken someone stabbed a car a few years ago with a Manix. I don't remember who it was but there was a long thread with pictures of multiple holes in a car all caused by a Spyderco.