ultimate hard use / abuse knife

[Fanglekai]

That, plus isn't it the responsibility of the guy making the positive claim to make the proof, rather than whining that other people can't disprove his claim?

Yep. It's not possible to disprove a negative. It's only possible to prove a positive claim. Even a negative assertion that sounds stupid can't be disproven. For example: "There are no pink unicorns in los angeles" is impossible to prove because those pink unicorns could be magical, invisible, or hiding somewhere. A positive claim would be saying "there are zebras at the zoo". That is a claim that can be proven because if one goes to the zoo and there are zebras, the claim is then shown to be true. You can't disprove a negative because there could always be some other factor that would change the outcome. The best you can do is reduce variables and test as much as possible to reach conclusions.

In the case of knives it becomes rather complicated to prove or disprove anything. "With regard to the 52100, what makes you feel that it is not well suited to prying at 62 RC? What evidence do you have to support this statement?" On the contrary, one would need to provide evidence to support that it is good for prying, rather than try to prove that it is not good for prying. In order to prove anything you'd have to figure out what thickness and geometry are going to be tested. If you make a thick Busse-style knife out of 52100 at 62 HRC and pry with it it's not the same as using one with a design like the Phil Wilson Southfork. The results would only be indicative of similar knives. This is why you cannot disprove a negative. Just because a design like the Southfork might snap from prying doesn't mean a knife made out of 52100 in the same shape as a BK2 would snap, so you cannot conclude that it's not good for prying because there are always more possibilities. You can, however, show instances where 52100 at 62 HRC does pry well.

 

[BePrepared]

Yep. It's not possible to disprove a negative. It's only possible to prove a positive claim. Even a negative assertion that sounds stupid can't be disproven.

This is incorrect. This is a commonly misspoken formulation of a rule of logic.

The correct formulation of this rule is "you cannot disprove a non-contradictory universal negative"

It is quite possible to disprove a negative. For instance, one can Disprove the statement "you can't break this knife" by breaking it.

The statement "There are no knives that can't be broken" is a non-contradictory universal negative and is therefore unprovable

The example you gave is a non-contradictory universal negative, and therefore can't be dis-proven without knowledge of all parts of the universe simultaneously.

It is possible to disprove a contradictory universal negative such as "there are no square circles" because the definition of a circle makes a square one contradictory.

You also can't prove a non-contradictory universal positive, but that's a different discussion

 

[Moses2792796]

This is incorrect. This is a commonly misspoken formulation of a rule of logic.

The example you gave is a non-contradictory universal negative, and therefore can't be dis-proven without knowledge of all parts of the universe simultaneously.

Actually it could be disproven just with knowledge of all parts of Los Angeles simultaneously.

 

[BePrepared]

touche! very true... we'll call that a "semi-universal negative"

 

[Fanglekai]

This is incorrect. This is a commonly misspoken formulation of a rule of logic.

The correct formulation of this rule is "you cannot disprove a non-contradictory universal negative"

It is quite possible to disprove a negative. For instance, one can Disprove the statement "you can't break this knife" by breaking it.

The statement "There are no knives that can't be broken" is a non-contradictory universal negative and is therefore unprovable

The example you gave is a non-contradictory universal negative, and therefore can't be dis-proven without knowledge of all parts of the universe simultaneously.

It is possible to disprove a contradictory universal negative such as "there are no square circles" because the definition of a circle makes a square one contradictory.

You also can't prove a non-contradictory universal positive, but that's a different discussion

You're right. I was being lax with my terminology. I was hoping to keep it simple as my point was pretty simple: try out various examples of knives in 52100 at 62 HRC to show either that it works for a prying knife or it doesn't. Until people test some knives all we have is speculation. I would venture to guess that thin knives will not make good prying knives but thicker ones like a BK2 shape out of 52100 would be fine for prying even at 62 HRC because of the knife's geometry.

 

[Fanglekai]

Actually it could be disproven just with knowledge of all parts of Los Angeles simultaneously.

The pink unicorns are magical. Good luck finding them.

 

[BePrepared]

The pink unicorns are magical. Good luck finding them.

Yeah, the pink ones are hard to find... blue is pretty much humdrum

if you do find one, tell no one. Pm me. I'll be there within 5 hours.... don't be greedy!

 

[hardheart]

52100 is not the best steel for prying and 62 Rc is not the best hardness for 52100 to pry with. Look at fracture toughness of 52100 at varying tempering temps and compare it to other steels. Don't worry, the numbers will trump the semantics. 52100 will have a higher toughness at lower hardness, and lother steels with have a higher toughness at comparable hardness levels. Do whatever you want to with your knives, just realize there is possibly a knife out there that will do it better.

 

[FortyTwoBlades]

Do whatever you want to with your knives, just realize there is possibly a knife out there that will do it better.

And that's why we all keep buying MOAR KNIFEZ.

 

[wjswiger]

OTK custom made Ozark Bowie or anything from David, Farid Mehr custom chopper, anything from Joe Hoover and Fehrman Last Chance.....really anything from Fehrman is outstanding!! I also like Marcus Lin.....have a Sharpened Prybar and it is my go-to knife when I'm in the woods; it's really really thick and heavy but is is insanely sharp so it cuts well and......just as the name mentions.....it can pry a buick out of the mud if needed!!

 

[stabman]

You want the ultimate hard use knife for you?
Make it yourself:

For me, this is the ultimate hard use knife.
Because I made it to suit my ideas of what my hard use tasks would be.

 

[Poez]

Wow: I did not even know that prying knives existed! Not sure I would ever need one: I do not remember using a prying knife for the first 45 years, so what are the chances...

 

[stabman]

Wow: I did not even know that prying knives existed! Not sure I would ever need one: I do not remember using a prying knife for the first 45 years, so what are the chances...

I don't understand the desire for prying either.
Chopping? Okay, I'm cool with that.

 

[BePrepared]

I don't understand the desire for prying either.
Chopping? Okay, I'm cool with that.

You've never been stuck in a Humvee with a jammed door and enemy troops approaching... neither have I, but it happened to one guy who used his knife to pry his way out

it can happen.

 

[stabman]

You've never been stuck in a Humvee with a jammed door and enemy troops approaching... neither have I.

That about sums it up for oh, pretty much 99.9999% of people everywhere.

 

[chiral.grolim]

52100 is not the best steel for prying and 62 Rc is not the best hardness for 52100 to pry with. Look at fracture toughness of 52100 at varying tempering temps and compare it to other steels. Don't worry, the numbers will trump the semantics. 52100 will have a higher toughness at lower hardness, and lother steels with have a higher toughness at comparable hardness levels. Do whatever you want to with your knives, just realize there is possibly a knife out there that will do it better.

Is the assumption that 52100's increased carbon content makes it less suitable for prying than perhaps 5160? If so, mustn't this be true of ALL steels with similar carbide volume (assuming similar martensite:austenite ratios)?
But in regards to prying (i.e. lateral stress), the material property of note (along with fracture toughness) is ultimate tensile strength which is fairly similar among steels and relates directly to steel hardness and dimensions. 52100 is stronger (resists taking a permanent bend) at 62 Rc than at 55 Rc. Also a thicker piece of 52100 is stronger than a thinner piece. So a hard thick piece of 52100 would withstand prying better than a thin soft piece. But the softer piece will take a permanent bend before fracturing and thereby signal imminent failure. Also, the softer piece will likely have improved impact toughness, but that is not a point of interest in regards to prying...

Anything wrong with these statements?

 

[Murphnuge]

Becker or ESEE unless you want to spend more than $200 , then go custom.

 

[BePrepared]

That about sums it up for oh, pretty much 99.9999% of people everywhere.

I agree. It's the other .0001% (60 thousand or so people) to whom incredible toughness is not just a hobby but an absolute necessity.

 

[frc505]

I've got a used Camp Tramp you could have. Sits in my sock drawer and collects dust. You could beat the snot out of it but it is not very good looking. Pm me if interested.

I'm not sure why you would spend 500 for a knife you plan to beat up, but different strokes I
guess...

Thats very generous of you kbog ! If he dont accept your offer
Hes crazy ! ... I would gladly beat the snot out of it if the
Offer stands lol!

Frank

 

[jdk1]

Wow: I did not even know that prying knives existed! Not sure I would ever need one: I do not remember using a prying knife for the first 45 years, so what are the chances...

Chances are slim luckily, but we are talking about a hard use/abuse knife here. One night, I found myself with some other gents standing on the front porch of a trailer house needing to very quickly get inside. Thankfully, the resident left a screwdriver nearby. We (he) were lucky that night, as the other options were more destructive. Now that I'm older and smarter (questionably) I prefer not to depend so much on luck. Since carrying a tool box doesn't work for me and since Murphy's Law dictates you won't have the crow bar when you need it most, I'll keep my pry-capable knife handy A man could get by wonderfully for years with one of those handy little sliding-blade fruit knives like my dad carried, but it would of been as useful as a boot full of cold urine that night on that porch. Take care.