S30V ! Hype or Hyper Steel?

It's an awesome steel. Really holds a nice edge, not to hard to maintain. There's a reason why almost every major American knife company uses s30v as their premium steel.
 
shike said:
S30V is a great steel no doubt. But whatever Victoronox uses it is also great and holds a terrrific edge.
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...which is way way behing CPM S30V edge...

I feel like I should stress this out. I am not sure why Victoronox poped up here, but it is no even close to CPM S30V. Sorry.

Thanks, Vassili.
 
Well, After 3 years using a SOG Twitch XL (AUS8) as an edc and then rotating to a Leek S30V. I can tell you that S30V is huge pain to sharpen properly compared to AUS8. It may keep it's edge longer but when it gets dull, it will be harder to sharpen up. It's probably a great 'Survival Knife' Steel but for EDC I'd rather have a Carbon Mora or My Twitch AUS8.
 
Again, see the hardness differences. The softer side of S30V is somewhat easier to grind, although still very difficult compared to 440A or 12C27. The other side is its more difficult to finish to a crisp, clean, sharp edge, holding on to a burr for dear life.
 
Moodino said:
Well, After 3 years using a SOG Twitch XL (AUS8) as an edc and then rotating to a Leek S30V. I can tell you that S30V is huge pain to sharpen properly compared to AUS8. It may keep it's edge longer but when it gets dull, it will be harder to sharpen up. It's probably a great 'Survival Knife' Steel but for EDC I'd rather have a Carbon Mora or My Twitch AUS8.
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What do you use to sharpen?

You probably need to use proper sharpening tool like some modern DMT. I has no problem sharpening any steel to hair whittling sharpness. Actually better steel usually easy to sharpen - smaller burr etc.

If you learn how to sharpen and it will be matter of few minutes than huge advantage of edge retention will pay off big time.

What is the point to have good modern steel and not to care about it properly?

Thanks, Vassili.
 
Try to avoid letting a knife get dull before you sharpen it. Far better to touch it up periodically. I recommend a Sharpmaker for most folders.

Moodino said:
Well, After 3 years using a SOG Twitch XL (AUS8) as an edc and then rotating to a Leek S30V. I can tell you that S30V is huge pain to sharpen properly compared to AUS8. It may keep it's edge longer but when it gets dull, it will be harder to sharpen up. It's probably a great 'Survival Knife' Steel but for EDC I'd rather have a Carbon Mora or My Twitch AUS8.
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sodak said:
I'm trying to stay out of this one HoB! :D

I've had bad luck with edge retention with my S30V knives. I've never had the chipping problems that others have had, however.

There's an old rub about D2 (which I completely disagree with) that says it takes a crappy edge and holds it forever. My experience with S30V is that it takes a crappy edge and holds it for 2 cuts. Obviously, that's an exaggeration, but true in general from what I've seen.

I've sharpened it on DMT, ceramic, and waterstones (edgepro), and only the edgepro gets me a good edge. I find it *very* difficult to get a good edge on. It loses it's edge fairly quickly, from my comparisons (non-scientific), I rank it with AUS -8A. I was planning on doing more testing, but I aggravated an old elbow injury, and don't really want to try again. I'm tempted to offer a couple of these knives to some enterprising soul who wants to compare them on the same test.

The knives I've used are: Buck 110 and Vanguard, small Sebenza, Spyderco Native (Walmart), and Spyderco Manix. I gave the Manix away to a friend when he graduated from the Police Academy. The best in edge retention are the Bucks, the Sebenza the worst (by far). I had the Sebenza re-heat treated (it went from 57 to 60.5) and Krein thinned, and that helped a lot. But it still wasn't up to my Queen or Dozier D2's, so I got rid of it.

I think with the right grind and heat treat (above 63 HRC), you could possibly see great things. Phil Wilson sure has, and he knows a lot more about these things than I do. What is really unreal is that:

1. Fallkniven's 3G is close to S30V (from what I've heard), and I have nothing but praise for it. It's a *great* steel for edge retention and ease of sharpening - close to 3V.

2. Almost everyone else on BF hasn't seen this, which makes me wonder if I wasn't nuts when I was using it.

I don't know. My personal opinion is that S30V is crap. But most everyone disagrees, and it makes me question myself because a lot of these people are folks whose opinion that I value. A lot.

Maybe it's time I dusted off what I've got left and try again...
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me2 said:
Not as long as it sells.

Keep in mind that there is a good range of hardnesses that different makers/manufacturers run on their S30V knives. S30V at HRc 55 probably wont be noticably better than 420HC at the same hardness. Holding a hair shaving edge depends mostly on hardness.

To answer the question in the title of the thread, there is some hype to S30V, but when heat treated optimally for the intended use of the knife, it can live up to the hype.

Sodak, was it you that said the line about D2 should read "it holds a crappy edge forever, after the good one is gone" or something like that?
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me2 raises a good issue. It seems to me that, if you do not know the hardness of the blade you are testing, you do not have enough information to characterize the steel. If you get poor results in your cutting test, you don't know whether to ascribe it to the steel or a suboptimal heat treat. It would at least be good to have the manufacturer's hardness spec, even if you do not have a hardness reading on the individual blades being tested.
 
I cannot be critical of the comparison test since there is not enough information to really try to explain the results. I would like to know the hardness of both of the blades. Based on my experience CPM S30V performs best at RC 61. Someone mentioned a S30V blade at 63 would be a good performer. I have not been able to push it that high. Normally the best as quenched hardness is about 62 and with a temper at 400, you end up with 61 +/-. On the CPM steels, 10V can be finished at 64 and CPM 154 up to 62 with good hardness toughness balance.

I just did some quick testing on rope with 4 blades of similar geometry all sharpened with Silicon Carbide stone and the wire edge removed with an India stone. To get an idea of how 440b would do I used an America made Dexter fillet knife. The steel could be 440A or 420HC. Hardness measured at 57 on my tester. This should be pretty close to the 440B blade. The other three knives were a CPM 154 (r 62) fillet knife, 154CM (r 61) fillet knife, S30V (61) and 10V (63) Coyote Meadow utility hunter. All were 0.010 behind the edge. I marked off 4 inches of cutting length. Cutting media was 5/8 manila rope. I cut on a scale to measure the down force. In the past, I have cut to 25 lbs and counted the cuts to compare the edge holding. This time I only went to 20 lbs to get a feel for how the Dexter would compare to the other higher carbide steels. Here is what I got:

Dexter 30 cuts
154CM 70
CPM 154 80
CPM S30V 70
CPM 10V 120

You can see the results follow the hardness. Past experience says that the higher carbide blades will tend to plateau out and continue to cut with higher force. If the “Tinker” is around RC 60 and very thin and the other CPM 30V blade is 58 or so then I could see how when cutting cardboard that one might get results similar to reported here. Cardboard cutting tends to favor a thinner blade and rope cutting is a better test for a higher carbide blade

Some thoughts on CPM S30V. This one has been pretty beat up on this forum. Results have been all over the map. I initially reported that this is an easy steel to heat treat. I still believe that. Compared to say S90V it requires a lower temperature and has a higher obtainable hardness. It also is less sensitive to quench cooling rate. All this makes it more forgivable. To get the best out of it I have a method that has given good results even on very thin flexible fillet blades.

Pre heat at 1500 and hold for 15 min.
Ramp up to 2000 to 2050 depending on your furnace controls and geometry
Hold for 40 min
Quench with forced air down to handhold temperature. Continue to cool down in water to about 60 degrees
Sub zero in Liquid Nitrogen for at least 2 hours. (note this step for me is quality control and others may argue that it is optional for this steel)
Warm from subzero temp in water
Temper at 400 for 2-hour cycles 3 times.

I do an initial rough grind before heat-treat but leave some material to remove after heat-treat. Grind at least .020 off the edge. I do one final temper after finish grind and polish to remove any residual stress from grinding and finish. Sharpen blade and do cutting tests on rope and do a twisting cut out of pine or fir to check for chipping. If there is evidence of chipping one final temper at a little higher temperature to improve toughness. The temps are specific to S30V but I follow the same general steps on all the CPM steels.

I like S30V for general use hunters and working knives where abrasive wear is in play. S90v and 10V are upgrades for this application. I recently did some major fiberglass repair work on my boat and used a couple of “shop” knives to trim cured epoxy glass. My 30v (61) and 10v (64) knives just kept cutting on this hard abrasive material. This is tough work for a knife. I favor CPM 154 now for fillet knives and kitchen knives. It has a little higher obtainable hardness and heat-treating is simplified since Turco can be used in place of foil for de carb protection. It finishes nice with less grinding belts and has great toughness even at RC62. It all boils down to the right steel for the application. Cpm S30V is still a good fit between the finer grain lower carbide steels and 90V and 10V. Phil
 
Phil Wilson said:
I cannot be critical of the comparison test since there is not enough information to really try to explain the results. I would like to know the hardness of both of the blades. Based on my experience CPM S30V performs best at RC 61. Someone mentioned a S30V blade at 63 would be a good performer. I have not been able to push it that high. Normally the best as quenched hardness is about 62 and with a temper at 400, you end up with 61 +/-. On the CPM steels, 10V can be finished at 64 and CPM 154 up to 62 with good hardness toughness balance.

I just did some quick testing on rope with 4 blades of similar geometry all sharpened with Silicon Carbide stone and the wire edge removed with an India stone. To get an idea of how 440b would do I used an America made Dexter fillet knife. The steel could be 440A or 420HC. Hardness measured at 57 on my tester. This should be pretty close to the 440B blade. The other three knives were a CPM 154 (r 62) fillet knife, 154CM (r 61) fillet knife, S30V (61) and 10V (63) Coyote Meadow utility hunter. All were 0.010 behind the edge. I marked off 4 inches of cutting length. Cutting media was 5/8 manila rope. I cut on a scale to measure the down force. In the past, I have cut to 25 lbs and counted the cuts to compare the edge holding. This time I only went to 20 lbs to get a feel for how the Dexter would compare to the other higher carbide steels. Here is what I got:

Dexter 30 cuts
154CM 70
CPM 154 80
CPM S30V 70
CPM 10V 120

You can see the results follow the hardness. Past experience says that the higher carbide blades will tend to plateau out and continue to cut with higher force. If the “Tinker” is around RC 60 and very thin and the other CPM 30V blade is 58 or so then I could see how when cutting cardboard that one might get results similar to reported here. Cardboard cutting tends to favor a thinner blade and rope cutting is a better test for a higher carbide blade

Some thoughts on CPM S30V. This one has been pretty beat up on this forum. Results have been all over the map. I initially reported that this is an easy steel to heat treat. I still believe that. Compared to say S90V it requires a lower temperature and has a higher obtainable hardness. It also is less sensitive to quench cooling rate. All this makes it more forgivable. To get the best out of it I have a method that has given good results even on very thin flexible fillet blades.

Pre heat at 1500 and hold for 15 min.
Ramp up to 2000 to 2050 depending on your furnace controls and geometry
Hold for 40 min
Quench with forced air down to handhold temperature. Continue to cool down in water to about 60 degrees
Sub zero in Liquid Nitrogen for at least 2 hours. (note this step for me is quality control and others may argue that it is optional for this steel)
Warm from subzero temp in water
Temper at 400 for 2-hour cycles 3 times.

I do an initial rough grind before heat-treat but leave some material to remove after heat-treat. Grind at least .020 off the edge. I do one final temper after finish grind and polish to remove any residual stress from grinding and finish. Sharpen blade and do cutting tests on rope and do a twisting cut out of pine or fir to check for chipping. If there is evidence of chipping one final temper at a little higher temperature to improve toughness. The temps are specific to S30V but I follow the same general steps on all the CPM steels.

I like S30V for general use hunters and working knives where abrasive wear is in play. S90v and 10V are upgrades for this application. I recently did some major fiberglass repair work on my boat and used a couple of “shop” knives to trim cured epoxy glass. My 30v (61) and 10v (64) knives just kept cutting on this hard abrasive material. This is tough work for a knife. I favor CPM 154 now for fillet knives and kitchen knives. It has a little higher obtainable hardness and heat-treating is simplified since Turco can be used in place of foil for de carb protection. It finishes nice with less grinding belts and has great toughness even at RC62. It all boils down to the right steel for the application. Cpm S30V is still a good fit between the finer grain lower carbide steels and 90V and 10V. Phil
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When you cut does edge hit some wooden base?

If so I suggest you to make something like this

Random-420.jpg


otherwise you are not cutting rope but base and impact from wood is much higher and random in such case.

Thanks, Vassili.
 
I do manila rope cutting when I test production blades that I have bought. Since these are production blades, I cannot control the heat treat like Phil Wilson does, but I do measure the hardness so that I have some concept of what I am testing. I made a simple jig to support the rope. The support has a gap to let the blade pass through. It is not as nice as yours Vassili, but the concept is the same.

I can comment on testing technique, but not on S30V results as I have no S30V blades to test.
 
Phil Wilson said:
Someone mentioned a S30V blade at 63 would be a good performer. I have not been able to push it that high. Normally the best as quenched hardness is about 62 and with a temper at 400, you end up with 61 +/-. On the CPM steels, 10V can be finished at 64 and CPM 154 up to 62 with good hardness toughness balance.
Click to expand...

I thought you had it up to 63, sorry for the misinformation!
 
Im just back from a week camping the main knives i used were a BRKT PSK and a spyderco UKPK.Both were well used during the week.
Without doubt the S30v held a edge better i can get 12c27 on a convex to wittle hair so it is my favourite stainless for this reason although ive learned it doesnt hold a edge anything like S30v.
I noticed that 12c27 micro chipped far easier i sharpened this knife 3 times during the week each time it had tiny chips to remove.
The UKPK hasnt been sharpened at all and also hadnt for a while before i took it camping. It did develop two micro chips that im going to sharpen out later but the blade is still about 90-95% as sharp as it was from the week before.
I was also impressed by the tip strength on the UKPK as its a very accute tip i stabbed it into lots of things and the tip is still as sharp and pointy.
 
nozh2002 said:
When you cut does edge hit some wooden base?

If so I suggest you to make something like this

.......

otherwise you are not cutting rope but base and impact from wood is much higher and random in such case.

Thanks, Vassili.
Click to expand...

If I were worried about impact on the edge from a hard surface, I wouldn;t use wenge for those testing blocks, or any other dense hardwood. Most have silica in them and are dense enough to affect the edge with each cut.

Granted, anything the edge touches will, over time, affect ist sharpness, but better to make those blocks out of a softwood like pine or redwood, or maybe phillipine mahogany or similar. Also, where the edge touches the base the grain should run parallel to the edge, like in your tall, U-shaped block. The blocks won;t last as long with softwoods, but they'll take less away from the edge.
 
Vassili, I did not go into detail on my testing set up since I have described it before. Yes I cut on a wood surface. I use Alder and I'm sure it does have some effect but it is the same for all the blades. It just acts like a stop if you ease up on the pressure after cutting the last few strands of fiber. I like your idea though, it takes out one more varible.

Sodak, OK no problem. I have seen other places where people have reported that I have 90V chef knives out there that are 63 hardness. Not so. The CPM steels, 30V, 90V, 60V, just do not have that high of obtainable hardness due the high alloy content and a tendency to be sensitive to quench rate. It may be possible in a Lab with very thin sections and an oil quench to get them higher but in the real world of heat treating a knife blade with the equipment I have, I have not been able to get them that high. No problem with 10V or 125V. Rc 65 is easily possible with them.

Phil
 
Phil Wilson said:
Vassili, I did not go into detail on my testing set up since I have described it before. Yes I cut on a wood surface. I use Alder and I'm sure it does have some effect but it is the same for all the blades. It just acts like a stop if you ease up on the pressure after cutting the last few strands of fiber. I like your idea though, it takes out one more varible.
Click to expand...

I test with and without base, effect was significant. I even start thinking to not cut rope but scratch wood under certain weight. If it works as a stop then impact on the edge may be very random - it may stop it hitting one part of the edge or another.

Thanks, Vassili.
 
Vassili, I have been experimenting with cutting leather. This is a slicing cut comparing several knives on the same pc of leather. The idea is to cut a flat piece without going all the way through. The blades have to be exactly the same with the same length "belly" on the blade. This takes some feel and practice. Leather is more abrasive than you might think and you can quickly get an idea of how a knife might work in the field on say a skinning job. In general I have found that the results follow the same general trend as rope cutting. Higher hardness and higher carbide percentage hold up longer. This is a pure wear test, not enough force to roll or chip a fine edge. So far I have just done 300 slices with each blade and feel the sharpness with my thumb pad every 20 cuts. Don't laugh, you will be surprised how you can feel the degregration of the edge. If you want to try this just pull your thumb pad along the edge very lightly. If it grabs it is sharp, and you can tell with in about 20 slices when the edge starts to smooth out. Not science and many may scoff but I think it is a better indicator than cutting thread or measuring force on a scale. PHIL
 
Phil Wilson said:
Vassili, I have been experimenting with cutting leather. This is a slicing cut comparing several knives on the same pc of leather. The idea is to cut a flat piece without going all the way through. The blades have to be exactly the same with the same length "belly" on the blade. This takes some feel and practice. Leather is more abrasive than you might think and you can quickly get an idea of how a knife might work in the field on say a skinning job. In general I have found that the results follow the same general trend as rope cutting. Higher hardness and higher carbide percentage hold up longer. This is a pure wear test, not enough force to roll or chip a fine edge. So far I have just done 300 slices with each blade and feel the sharpness with my thumb pad every 20 cuts. Don't laugh, you will be surprised how you can feel the degregration of the edge. If you want to try this just pull your thumb pad along the edge very lightly. If it grabs it is sharp, and you can tell with in about 20 slices when the edge starts to smooth out. Not science and many may scoff but I think it is a better indicator than cutting thread or measuring force on a scale. PHIL
Click to expand...

I know that - I did quite a bit of splinter cuttings out this way, whitteling skin is good test for sharpness as well as hair whittling.

But it should be some way to represent as a numeric values to put into table. It gives more food to thinking. Like I found that some steel keeps high sharpness longer then other but then lost average sharpness very quickly - it is hard to find if you do not have good table to look at.

So far statistical thread measurement works best for me. I did try different thing recently, but realize that old way I used beginning of this year probably best so far. I am going to start another testing soon I hope.

Thanks, Vassili.
 
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