SK-5 Bushman failed in latest "Joe-X" Destruction Test

I checked an inflation calculator to see how much the older Carbon V Recon Tantos appreciated in value.

The one I purchased in 1997 was $70.00 at a discount mail order knife company and IIRC the MSRP was $90.00.

The prices would be $122.62 and $157.65 in today's dollars, so they did rise in value, but not to a degree worthy of investing, especially when you won't know which ones will rise in value.
 
deadzonepatrol said:
I don't think a production knife is going to withstand bending to 90 degrees. I just checked up on the ABS Master Smith test requisites. They require a knife to bend 90 degrees without breaking, although the edge can crack up to 1/3 the width of the blade. This is to test the smith's ability to soften the spine for toughness, whilst hardening the edge for performance. Most production knives are not differentially heat treated, although some, like TOPS are. It seems to me that the Bushman knife in the video did pretty well for a cheap production knife.
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That reminds me of this video:

6ZiQT0.jpg
 
KenHash said:
That reminds me of this video:

6ZiQT0.jpg
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That's got to be the exception, not common, don't you think? Any piece of steel that is made flexible enough would be able to bend past 90 degrees. Not necessarily a good thing. It could mean that it's "whippy", as in some Windlass swords. I don't recall seeing any of the large bowies being bent to 90 degrees in Cold Steel videos.

I still think that Bushman video in post #1 is a PASS, not a fail. Especially considering that it's a $20 knife. I'll have to check out the other posted videos later.
 
I think a blade needs to be a certain length to be "whippy."

My Windlass arming sword is not whippy but my hand and a half swords are. Their blades are also more narrow than the arming sword.

A Master Tanto has only a 6" blade and I think even the Magnum Tanto XII is too short to be "whippy." These are also thicker than either of my Windlass swords.

Maybe a Kobun-like knife with a 18+ inch blade would get that effect.
 
Benjamin Liu said:
I think a blade needs to be a certain length to be "whippy."

My Windlass arming sword is not whippy but my hand and a half swords are. Their blades are also more narrow than the arming sword.

A Master Tanto has only a 6" blade and I think even the Magnum Tanto XII is too short to be "whippy." These are also thicker than either of my Windlass swords.

Maybe a Kobun-like knife with a 18+ inch blade would get that effect.
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Yeah, I was saying that just because a knife is super flexible, that isn't necessarily good. Not that a Master Tanto is whippy. (I'm sure it's not.)
 
deadzonepatrol said:
That's got to be the exception, not common, don't you think? Any piece of steel that is made flexible enough would be able to bend past 90 degrees. Not necessarily a good thing. It could mean that it's "whippy", as in some Windlass swords. I don't recall seeing any of the large bowies being bent to 90 degrees in Cold Steel videos.

I still think that Bushman video in post #1 is a PASS, not a fail. Especially considering that it's a $20 knife. I'll have to check out the other posted videos later.
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Yes I thinkit's an exception. Most knives bent to that degree do not return to normal. There are multiple knife bending test videos on the net and they all permanebtly bend the blade.
I can however attest to the Master Tanto and all other CS Tantos (which I have owned) were not "whippy" in any way. Find it hard to imagine any "whippy" blade going through a car hood.
 
I have never understood the importance of these excessive bending tests. I used a KaBar for years as a digging and prying tool, so much so that I ultimately did give the blade minor bend at the handle, and yet I never managed or imagined myself applying enough force to bend the blade to some insane angle.

What would you ever do that required that?
 
Chris_Texas said:
I have never understood the importance of these excessive bending tests. I used a KaBar for years as a digging and prying tool, so much so that I ultimately did give the blade minor bend at the handle, and yet I never managed or imagined myself applying enough force to bend the blade to some insane angle.

What would you ever do that required that?
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Using your knife as an egress tool during perhaps a fire, prying your way into a bathroom that someone is locked in and drowning, etc. In other words, an emergency.
 
James Morgan Ayres, a retired Special Forces soldier, wrote about using a knife to save himself from getting swept downstream by a current. I think it was in his book The Tactical Knife. He said that he once used a knife to stab into a river bank to pull himself out of rushing water.

Ideally, what you want is a knife that will not break and will not bend. If it breaks, you're screwed. If it bends too much, you can still be screwed. Since there is no steel that is unbreakable, bending tests prove "toughness", as in "it bends but doesn't break". But like I said, you still want a good balance of both strength and toughness, which two concepts are not necessarily the same. What happens if you are caught in a current and stab into a river bank and your knife bends too much?
 
Chris_Texas said:
I have never understood the importance of these excessive bending tests. I used a KaBar for years as a digging and prying tool, so much so that I ultimately did give the blade minor bend at the handle, and yet I never managed or imagined myself applying enough force to bend the blade to some insane angle.

What would you ever do that required that?
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Why are novice knife makers required to bend their blades as part of their qualification to be called a professional knife maker?

It's a rhetorical question: The answer is that it's an objective test of toughness.

Maybe a better question is: Why is that it's only Cold Steel that show bend tests of their various blades? I've never seen a RMK, Gerber, Kabar, Kershaw, et al bend their blades. I wonder why?
 
dogstar said:
coloradowildman coloradowildman has said in the past that the heat treat might have been altered to cater to the consumers' fixation on edge retention at the expense of toughness. I believe there is something to that notion.

I just watched a video last night from an Aussie showing how he chipped his AUS8A Marauder by chopping saplings, so this might not be limited to SK-5 with Cold Steel.
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If so that would suck super bad, I don't care about edge retention in relation to toughness. There's a good balance to strike and Cold Steel is missing it wildly with their SK-5.
 
Albin said:
Why are novice knife makers required to bend their blades as part of their qualification to be called a professional knife maker?

It's a rhetorical question: The answer is that it's an objective test of toughness.

Maybe a better question is: Why is that it's only Cold Steel that show bend tests of their various blades? I've never seen a RMK, Gerber, Kabar, Kershaw, et al bend their blades. I wonder why?
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As Lynn Thompson said in one of his proof videos, "where's their proof?"
 
https://imgur.com/a/Z4U19ot
Ok, guys. I finally got around to doing a hardness test and chemistry burn. Check my results out for yourself and see what you think. Remember, this is just for fun. I am not a metallurgist but I am not new to this stuff. I don't have an axe to grind with Cold Steel (Haha!) and i have no connection to the knife making industry.
 
Before I go any further, my hardness readings were;
56.6
56.5
56.2 Rc

Ok, the first thing I notice is Carbon is a bit high for Sk-5. That's the reason you see 2 burn results. It could possibly be reading a little higher than actual because my closest standard for Carbon is .98%. How far off? I don't know. Probably not much.
Next, Phosphorus is for some reason higher than expected but I don't have a standard to set it that low. In this case, I don't think it really matters.
I suspect the rest to be reading very accurate.

Oh, yeah, all the testing was done on a Cold Steel SRK in SK-5 purchased from a reputable vendor 2-3 years ago.
 
Bloodloss said:
Before I go any further, my hardness readings were;
56.6
56.5
56.2 Rc

Ok, the first thing I notice is Carbon is a bit high for Sk-5. That's the reason you see 2 burn results. It could possibly be reading a little higher than actual because my closest standard for Carbon is .98%. How far off? I don't know. Probably not much.
Next, Phosphorus is for some reason higher than expected but I don't have a standard to set it that low. In this case, I don't think it really matters.
I suspect the rest to be reading very accurate.

Oh, yeah, all the testing was done on a Cold Steel SRK in SK-5 purchased from a reputable vendor 2-3 years ago.
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56-57 Rc... seems pretty reasonable, as it the knife should not lack for toughness. Am I right?
 
dogstar said:
56-57 Rc... seems pretty reasonable, as it the knife should not lack for toughness. Am I right?
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Correct.
I just read an article that claims if the carbon is high, SK-5 can be more brittle.
I think it was wise for Cold Steel to run a modest hardness. Let's be real, at the prices they offer these knives for, we shouldn't expect the purest, most bestest SK-5 in the land.
It would have been interesting to do the same testing on a Work Tough Gear knife and show the results side by side....
 
Bloodloss said:
https://imgur.com/a/Z4U19ot
Ok, guys. I finally got around to doing a hardness test and chemistry burn. Check my results out for yourself and see what you think. Remember, this is just for fun. I am not a metallurgist but I am not new to this stuff. I don't have an axe to grind with Cold Steel (Haha!) and i have no connection to the knife making industry.
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Cool, thanks for taking the time to do this. That turned out awful high in carbon content for SK5. A result of .937% is obviously closer to 1095 than Japanese SK5, which is supposed to be close to American 1084. So that was from an SRK purchased around 2019-2020, eh? I think that might have been the time that prices for those knives suddenly dropped, a significant drop too. And I remember thinking, I hope the steel sourcing hasn't changed.
 
Bloodloss said:
Correct.
I just read an article that claims if the carbon is high, SK-5 can be more brittle.
I think it was wise for Cold Steel to run a modest hardness. Let's be real, at the prices they offer these knives for, we shouldn't expect the purest, most bestest SK-5 in the land.
It would have been interesting to do the same testing on a Work Tough Gear knife and show the results side by side....
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Yeah, but if the carbon content is close to 1095 steel, then it's not really SK5, it is 1095. And if those recent toughness tests on bladeforums are accurate, (and I think they were accurate, for the most part, although you might quibble with a few results), 1095 is nowhere near as tough as 1084 (SK5). It was shocking to see the data. 1095 was at 10 ft/lbs and 1084 was like 25 ft/lbs at similar hardness.
 
Joe-B is much better in destroying everything
Joe-X is just a toddler, sissy carpet munchkin ...
 
deadzonepatrol said:
Yeah, but if the carbon content is close to 1095 steel, then it's not really SK5, it is 1095.
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Keep in mind, you can only call it another grade (1095) if all the other element percentages match up. And if they do, then you're saying Cold Steel advertised one thing and delivered another? Be careful. This was just for fun. But I get what you mean.
deadzonepatrol said:
1095 was at 10 ft/lbs and 1084 was like 25 ft/lbs at similar hardness.
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I never would have guessed. Interesting...
 
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