VG10 steel

Joined
Apr 29, 1999
Messages
9
I´m cosidering to buy a Fallkniven A1.
Seems to be a very robust knife for its size and very suitable as survival knife, but I´ve never used a blade made with this steel.
Acording to an article about the knife in Tactical Knives the steel is stronger and keeps an edge better than ATS34.
What do you think about VG10 steel?. And about the overall performance of the knife?
 
I just picked up a Spyderco Calypso in VG-10, but I haven't really done any serious cutting with it yet. A look at the steel stats shows that VG-10 has a quite respectable carbon content of 0.95-1.05, very close to ATS-34 or AUS-10. Its other salient features are a high molybdenum and phosphorus content, which are likely just for ease of machining, and an enormous cobalt content. This last feature will supposedly contribute to both strength and hardness. Mostly what I've heard about the steel credits it with cutting performance similar to ATS-34, but without quite the same brittleness and sharpening difficulties I've seen firsthand with that "super-steel." I can't say for sure yet, but from what I've heard it looks like a real winner of a steel, only seriously outperformed by carbon steels and particle stainless types.

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-Corduroy
(Why else would a bear want a pocket?)
 
I have had a spydie moran for 9 or 10 months now and have taken it on a few short canoe trips. It perormed extremely well as our kitchen knife . As for ease of sharpening, I don't know yet since it still shaves quite well and has not yet neede sharpening. Seems to be a very good stainless.
 
My A1 arrived yesterday from Tom Lagan. It is a very thick solid knife, in the same class as the pATAK.

http://www.physics.mun.ca:80/~sstamp/knives/a1.html

I have only done slight work with it so far but I would guess that its edge holding is below MD's O1 and D2 on soft materials. The edge came fairly coarser, I have not sharpened it yet so I don't know if this is because of the high alloy content (probable) or just a coarse finish (which is good).

I chopped up 3 sections of 2" radius seasoned wood and sliced up some cardboard and noticed a slight degradation of the edge when I did some slicing tests on bundled cloth. I will be doing more work on it in the upcoming weeks and will be running it against a Recon Scout from Cold Steel. If you are interested in a particular aspect just let me know.

-Cliff
 
The July issue of Tactical Knves has an article on VG-10 pg 22.

Also note that Fallkniven VG-10 is custom tempered for strength and edge-holding.

Cliff
Glad you have had a chance to start the testing. I look forward to the rest of the review.

Tom
 
Sharkteeth - VG10 tested significantly superior to ATS34&55 in corrosion resistance. ("Q"-fog corrosion analysis). In edge retention, VG10 tested at least as good and often better than ATS steels. (CATRA Edge testing analysis).
sal
 
Was that due to elemental content or just its ability to take a high finish? I notice that my Calypso has one heck of a finish on it
smile.gif
What's the trick? The chromium that I usually think of for finish isn't all that high; is it something to do with all that cobalt?

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-Corduroy
(Why else would a bear want a pocket?)
 
Sal exactly how was the edge retention testing done and what factors did it rate (impact resistance, lateral deformation resistance, abrasion resistance, adhesion resistance)?

-Cliff
 
Thanks for all your comments.
Cliff, edge retention and resharpening seems to be very good, and as a survival oriented tool the other aspect I consider important is lateral strenhgt in case you have to do some priying. Is VG10 a good steel for it?.
Thanks.
 
Sharkteeth, I will be able to give you a comprehensive answer on the durability of VG-10 in about a week. I have some other knives coming that I want to test its cutting performance against and I don't want to risk breaking it before they get here.

I have however tested it in 4 areas of durability so far.

First I pounded the butt on a concrete brick until it cracked (the brick not the knife). This took quite a while because the knife is very light. All that happened is that the extended tang was very slightly dimpled. Because the tang is extended it protected the actual handle from the impacts unlike say the Spec Plus line from Ontario. I really, really like the extended tang.

Second, I looked at its ability to absorb lateral shocks by throwing it at 1.5 turn distance from a 2x8. It took me awhile to get the right amount of force down so the blade was mostly just banging off of the wood and then landing on the ground, sometimes digging into it. The knife was uneffected by this except for a slight dulling of the edge, probably from digging in the ground.

Third, I actually threw it so it would stick into the wood at this distance. Because of the relatively thick tip this meant a fair amount of force was necessary. The knife is nice and heavy for its size which gives it a nice feel in this area as its high moment of inertial makes it resistant to side rolling. The tip was not impacted or bent by the throwing. The 2x8" could not make the same claim.

Finally I spent some time stabbing and then digging in 2x8" and 4x4". The knife is very solid and showed no flex at all even when breaking pieces of the wood out after full power stabs.

I will be looking at some rougher aspects like actual prying and some stiffer cutting chores in the near future. Based on its initial performance I highly doubt that it will have any difficulty with them.

Oh yeah, I have not protected it with any type of oil or anything and I have left the crude from any cutting on it over night each time I have used it to test the corrosion resistance. So far, after about a week, it has shown no signs of spotting.

-Cliff
 
Courduroy, you who wears the cloth of kings, please elucidate on your remarks, and educate this ignorant one.

You call ATS-34 a 'Super Steel.' I thought that this term was reserved for non-ingot steels (particle metallurgy), which contain higher amounts of different alloying elements than would be obtainable using the traditional ingot methodology.

I thought ATS-34 to be a traditional ingot steel. Certainly it could be made in the particle metallurgical fashion, but I fail to see, based on the alloy composition, any need to do so. For example, M2 is a traditional ingot steel. M4, which has a higher V level than obtainable using ingot technology, is always made using the particle metallurgical technique.

Further, can you inform me of who makes this VG-10 alloy?? I came up dry on my usual search sites for this steel, but it is on the Spyderco steel chart. I wonder if it is known by another name?

Thanks for your help. Walt
 
Cliff - A blade is sharpened by our sharpening experts to a particular bevel and sharpness ("Scary sharp"). Same guy on the same equipment is very consistant. Edge angle is varified on a Goniometer. The blade is fastened to a reciprocating arm that cuts a chemically consistant card stock. This stock contains a particular percentage of abrasives, etc. The pressure is controlled as is the distance of the cut. The computer measures Initial Cutting Performance (ICP) (total of 1st 4 cuts) and then total cutting performance based on the linear inches of card stock cut in a predetermined number of cuts.

Walt - VG10 is produced by a small foundry in Honshu island in Japan. It is an ingot steel. A good combination of "stuff" carefully blended.
sal
 
Sal, that it basically what I assumed it was, I am curious though as to how the cutting performance is measured? Is it just the resistance that the blade experiences or is it depth of cut as a function of applied load?

The problem with very controlled testing in this manner is that its not overly relevant to actual knife use by people. It is just evaluating one part of edge retention (of which there are many aspects) and only evaluating that particular performance area in a very narrow range of use.

If I was a machine doing the cutting in the manner described I would be very interested in the results obtained by that test. However for people you would get a much more meaningful result if you had an actual person do a bunch of cutting on various materials and then do an edge test. As long as the volume of material cut was kept high the mean effect of the cutting would be very consistent from knife to knife even though there might be a large variance in the individual cuts. By increasing the volume of cutting material you can get the consistency of the mean effects as low as you want.

You could actually simulate what a person would cut like by having the machine vary the pressure, angle and actual cutting stroke. While I would be interested in the robotics aspects of that design it would be really silly from a practical point of view as it would be far easier to just get someone to do it.

Back to the VG-10 in the A1. It is definately more abrasion resistant than the AUS-8A in my Calypso Jr. and VG, and it is far more resistant to deforming under impacts. I would estimate that its charpy value is significantly higher.

-Cliff
 
Sorry for the confusion. I wasn't aware that folks were reserving the "super steel" term for particle types - ATS-34 is a traditional ingot steel type, and I was speaking sarcastically, anyhow. In my experience with ATS-34 in production knives (many Benchmades, my titanium Police, a few others), it is gritty and crystalline and a real pain to sharpen, as well as unacceptably brittle. Edge holding is excellent but I have a very hard time bringing up a truly "scary" edge, even with a belt grinder and power strop.

For that reason I was making fun of the "steel to end all steels" attitude that some people have about ATS-34, which has led to its widespread adoption. I'm pleased to see that this attitude has decreased substantially in the last few years but I have been a bit "out of the loop." Particle steels really are "super steels" and their use in production knives is a great trend (thanks Spyderco!), but of traditional steels I'd much rather GIN-1, or even AUS-8 or 440C, to ATS-34. Someone who doesn't enjoy keeping a knife really sharp might feel differently.

One final note: I've made about two dozen knives in ATS-34 myself, all heat-treated by Texas Knifemaker's Supply, and they show none of the poor qualities I have seen in production ATS-34 (not bragging, it's got nothing to do with my work). I think they are slightly softer, though edge-retention is still great. This makes me think that something in the heat-treatment process of major factory knives is causing the problem. Also, never judge the steel in a handmade knife by what you've seen in production types
smile.gif


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-Corduroy
(Why else would a bear want a pocket?)
 
Hello,

We talk about VG-10 here and we use strange english !

http://www.bladeforums.com/ubb/Forum3/HTML/000476.html

Cheers,

JM
 
Sal,

Thanks for your input, I have been looking into one of the Fallkniven models myself.
It's reassuring to hear that stuff performs well.

Nemo,

you would'nt happen to have a better address for that would you? The one you mentioned is no longer there.
frown.gif


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God bless!

Romans 10:9-10

"Military" Fans Unite!!
 
Cliff - we use depth of cut (total) as a function of applied load. Consistency is a bigger problem than appears. The "various" materials" cut present tremendous variation. Magnified by total cuts, became less accurate. Our first machine used a specific foam material on the basis that it would be consistnt. No so. batch to batch varied and the total cuts became skewed. In our current tester, the material that we use is custom made in a factory that does that. controlled percentages of abrasives, wood stock, glue, etc. A combination created by some very bright guys over a long period of time (20 + years). It may not tell you everything, but it tells us a great deal about "how sharp" a steel will get and "how long" it will hold that edge (refuse to give up molecules).

We also control pressure to very close tolerances, difficult to do when using humans. We still use humans to create the edge. But they are "very good at what they do".

We also take photos with an electron microscope to study the grains structure under loads and response to same.
Hope this helps.
sal
 
Sal, I have been toying with that idea myself. It would not be overly difficult to make a pressure sensor give the required information about cut depth vs applied load. I should stop putting it off and construct something.

The "various" materials" cut present tremendous variation. Magnified by total cuts, became less accurate.

Sal, as I told Bob Taylor :

http://www.bladeforums.com/ubb/Forum1/HTML/001940.html

Uncertainties or errors do not work this way. In fact they behave in the exact opposite manner. The more of a material you cut the more consistent your results become. If you did 100 cuts through cardboard and compared two identical knives the difference would be 10 times less than if you compared them after one cut. To understand this in detail just read over the section on sampling distributions in any introductory statistics text.

As an example, take the current 2000 members of bladeforums. Now if me and you each took 10 people at random from the total population of members and compared the average ages from our groups there would likely be a big difference. But as we took larger and larger samples, the mean ages of our groups would converge. If we each took 1000 people at random the means would be almost identical. This is the effect I am talking about.

We also control pressure to very close tolerances, difficult to do when using humans.

Even though a normal person cannot get really precise angle or pressure control of a knife, on any single cut, the mean effect of a lot of cuts will be very consistent. You can get whatever precision you want by just having him cut more stuff. This is also a direct replication of actual use which offers much more valuable information as to how the knife will behave for the ELUs.

Machines are all well and good, and very precise measurements can never hurt, however neither of them are necessary for scientific work nor do they strengthen an arguement by themselves. When doing any experimentation you always have to look at just what you are trying to figure out and make sure that it is logical to extrapolate from the usually very fixed lab conditions to the very dynamic real life situations.

For example the last time I did a prying test I was harshly critized by a friend. What I was doing was very carefully increasing the load until I surpassed the yeild strength of the knives. He pointed out, quite correctly, that while this was all well and good it was not overly meaningful in a general sense as I don't actually pry like that. So after I did my careful controlled testing I did some actual dynamic prying as the final step on all the knives that passed the first round.


-Cliff
 
Cliff - If I make a cut on my rope and get a response of X. 100 cuts on my rope might yield 100X.

Now you cur your rope. In reality, your rope was manufacturered by a different company and may be a slightly different thickness, or a slightly tigher weave or maybe a stronger hemp. Let's say that in reality your rope is actully 10% less resistance (taking 10% less pressure to achieve the same results). Is that 100X-10%? Is 100X = to 100X-10%?

My knife cut my rope 112 times with the factory edge that came on my knife.

You used the same knife, but resharpened the knife before making the cuts on the rope.

your knife cut the rope 140 times. However, since you gained 10% because my rope was harder to cut. Your also gained another 10% because your resharpening was better than the factory edge. 140 cuts less 20% = 112.

How do we truly compare? Just some thought to share on random sampling.
sal
 
Cliff,

Sal's test problem is from Non-random variations. The batch-to-batch variation of test materials can dominate the random variations of the edge being tested. Another problem with high cut cycle repetitions as a test standard is that they can wipe out the edge being tested so early that you are really comparing secondary bevel characteristics. This is a progressive process rather than a random process. 100 cuts on a single blade is not the same as 100 single cut tests on seperate blades.

What I would like to see is a graph of cut depth divided by pressure verses the cut number. This would allow you to see the wear out progress.
 
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