Steel toughness testing - 4V, M4, and S90V
ฝัง
- เผยแพร่เมื่อ 10 ก.ค. 2024
- This video addresses the subject of toughness testing with knife steel. The steels used are CPM 4V, CPM M4, and CPM S90V. The video has discussion about toughness testing and documents toughness testing for the steels mentioned.
- วิทยาศาสตร์และเทคโนโลยี
Toughness is even more elusive to test in a standardized way than edge retention, I think your idea is great and well executed
Cedric & Ada Gear and Outdoors thank you, Pete. Toughness testing is really tricky. Lots of variables. I’m not sure I did the subject full justice, but I thought the idea of the staples was good.
It's early in the process and variables can still change before the format of the test is standardized. I encourage testing knives in groups where edge thickness is similar against folded staples. Regardless, another awesome video that I enjoyed for free. I will stop back seat driving now.
Have we even defined toughness yet? (Beyond the old charpy ductility test, which is valuable but not definitive)?
JacksonKnives here’s Crucible’s explanation of toughness. “Toughness, as considered for tooling materials, is the relative resistance of a material to breakage, chipping or cracking under impact or stress. Toughness may be thought of as the opposite of brittleness.”
@@michaelchristy4982 That sounds reasonable, but shouldn't the definition line up with a measurable property that's relevant to the task at hand? Charpy tests measuring absorbed energy work very well for things like bolts where elongation is desirable, but what does it really mean for an edge in one steel to better "resist breakage" than another steel? Is a catastrophic roll really better than a chip if you've got three more hours of chopping to do? Why do we talk about laminated steel and drawn-back spines as beneficial to "toughness" if the edge is where the damage happens anyhow?
I appreciate the tests like this you do. Interesting for sure.
Another great video. Good job sir, already looking forward to the next.
Literally the video i was looking for, buying an S90v bugout soon, but I could not find a real-world toughness test. This was a great video 🔥
Excellent findings on your test. I did a somewhat similar testing with M4, 4V, and REX45. 4V and M4 are not far from each other in terms of damage from my test. And with your tests showing the same result, it confirms it. Great video.
A.S.O.K.A Edge thanks.
I love all of your videos and thank you greatly for taking the time to share with the community. I find you to be honest, diligent, thoughtful and methodical. While other channels entertain with knives, you teach about the fundamentals that real knife nuts obsess over. You don't just give specs waving blades around. This test in particular was a great new branch for your series. BBB really seemed to get things fired up regarding toughness!
My constructive criticism is hard to give as I don't much like hearing it personally. Growth isn't easy. And, your video is obviously better than many commenters below or my own. With all that said... I think more regarding thickness behind the edge should have been mentioned. I think you said 30 inclusive, but that's not all the info we need. Also, commenters said the staple needs to be bent over, I agree. It's early in the process and variables can still change before the format of the test is standardized. I encourage testing knives in groups where edge thickness is similar against folded staples.
Regardless, another awesome video that I enjoyed for free. I will stop back seat driving now.
ToxicityAssured I don’t know how much those factors would really matter. The testing and prep for this video stretched over weeks. In that time, I tried making things more extreme by hammering through staples until they cut have. The damage for that followed the same pattern and looked the same. (Surprisingly enough.). If I had found a difference hammering the knives through (which I thought I would), I would have included it. As it stood, it would have just been extra that led to nothing.
The knives were at 30 inclusive, but that’s the edge angle. The thickness behind the edge is measured on the primary grind, not the edge bevel.
Very interesting test. And I really like the idea of how you testing the knives, Something real world that people can actually relate to.
We need you back, Nero!
Great vid, thanks for addressing the factory edge vs sharpened edge...I find this subject interesting and some fellow tubers are touching on it too.
that BBB knife is a beauty
EXCELLENT review!
Oscar
Hope to one day be blessed to work with BBB using 4V. I’m swamped with knives that are well executed for outdoor task and my thinner ones out perform the heavy’s and are more versatile. Need to add this format to my future consumption of knives
Good video love the big blade .
little woody thanks. Yeah, Big Brown Bear does some amazing work.
Great video
Outstanding.
Your videos have become a benchmark for me. Thank you.
4v is some really incredible stuff.
I like edge stability testing, as much as edge retention testing! It does seem it plays a big part in real world use. Wonder how that Spyderco in 52-100 at 62hrc would've held up? Good vid, love to see more like these.
i would like to see you run a similar test with various different knives in the same steel. i would like to see if thickness behind the edge or heat treat differences had obvious effects on the results.
Hi Michael,
I’ve been watching your videos for quite some time now and impressed with your knowledge of the many varieties of steel, ingredients, heat treating, sharpening techniques, etc.
You seem to be able to cut cardboard with S110v forever. My Spyderco Military with the same steel dulled out in no time with very little use. Don’t understand why. I got my knife about a year ago, carried it for a few weeks and ..... dull. It’s been in my drawer since. Have had better carry success with S30v. Just saying. Love your videos!
Dear God that Big Brown Bear is makin me drool!
This is Absolutely 100% relevant.
I've been saying this for a while..
CATRA testing and CHARPY testing dont necessarily equate to real world application.
Alot of the numbers we read in a controlled environment dont come out the same in a folding knife in the real world.
Thank you for doing this test.
Awesome.
SuperSteel Steve I agree, there should be some testing that includes some variables.
@@michaelchristy4982 The actual world of knife use is full of variables.
I'm my opinion a 100% sterile test is irrelevant.
It doesn't apply to what we as users do.
Not to mention on the subject of toughness CHARPY tests dont use knife blades at .20 thou behind the edge with a 30° inclusive edge.
They test pre cracked steel blanks lol
SuperSteel Steve I think both kinds of tests have there value, but let’s leave the catra and charpy tests to the companies, while you and I stick to tests with variables.
@@michaelchristy4982 sounds like a plan brother.👊👊👊
Hey Michael, I admire and got inspired from what you do. You helped me with my M390 PM2 and took my sharpening skills to another level. Thank you again.
I wanted to ask you one thing:
Have you ever had your hands on CPK (Carothers Performance Knives)? They have fixed blades from 3" up to 12" (even now making 18" sword). Nathan Carother is magician of heat treatment. He mainly works with CPM 3V. And created his protocol which is called Delta protocol, now it is like brand, his 3V is being called D3V. Amazing performer. Here is what Nathan says:
"The steel is Crucible CPM 3V at HRC 61-62 with a fully optimized heat treat with very good edge retention and edge stability. You'll be surprised how sharp this gets and how well it holds an edge. If you have never used 3V this hard and thin, it is gonna blow your mind."
And
"A side effect of this heat treat is a higher percentage of free chromium, so although it is not stainless, it is nearly so."
He cuts nails, cuts bolts, cuts cinder blocks with his knives.
I would love to see your review about one of his knives. They are usually sold at bladeforums at their subforum and if one cant grab from Nathan (as their 10-20 knives sell in seconds every 10-15 day) there is second hand market where some collectors or regular guy sell them for bit extra price (around 25-50$ extra). I do own their Field Knife 2 5" blade and awaiting for EDC 3" model. Field Knife performse amazing (second hand price is around 300-350$ and EDC is from 250-300$). You will be surprised how easy it is to sharpen (like carbon opinel) but resists abuse and holds edge without any problems. I have had regular 3v knifes, boker folder, coldsteel and other maker knifes but Delta 3V is completely different thing. I think you must try it.
I even wrote about my small sharpening experience on their subforum and said that you influenced me a lot.
Thanks a lot for everything. I just want you to try and enjoy their D3V it will change your mind about some things lol. And if you have one, I want to see and hear your review about CPK D3V. You can check Nathans youtube page: Nateaim
Be healthy.
Nika (Miracle- at bladeforums)
Nika Sarjveladze I’ve seen his knives and his videos, but it’s been a while. Glad to hear he’s doing good.
@@michaelchristy4982 Yes he does, wish that I lived in USA, I would send you his knife to try, test (and maybe if be lucky get review). I'm from small country under Russia, called Georgia. I just love every sharp thing lol, so I have had many different knives but his knives changed my experience. How to tell, in terms of edge retention, D3V compared to cold steel 3V is like to compare cold steels 3v with 10V lol. And in terms of toughtnes it's tought like S7 steel or evennore. You just have to try. I didnt knew if you have heard about them as they are small "family" business.. I respect you, and I wanted you to try and enjoy it. (And seeing your review would be amazing)
Thanks for a reply.
Be health with your beloved one.
Nika
I am a former lab teck great data. Thanks
Jay P. Thank you.
Thanks for taking the time to do this test!
What’s your favorite folding knives blade steel for edc?
Cark Nelson S90V, but then I like a lot of the models that Spyderco offers with S90V. If you look at my Instagram, I’m guilty as sin for loving that steel.
Michael Christy
Awesome my only s90v is the spyderco military I need some cutlery shoppe orange knives in s90v I think.
Cark Nelson nice. I didn’t get a chance to pick those up, but I have been tempted.
Michael Christy I am extremely addicted to s90v over this past year myself, mainly from all the wonderful tips your vids provide, I can sharpen it much more effectively than I used to and it proves to be a God-send for heavy farm duty tasks...crazy eh? Who woulda thought s90 the heavy duty farm steel? 😂
Glad you threw in S90V. I was also surprised. Often times I find the “hype” of a steel does not always match real world use. Interesting how Rockwell can effect composition of carbides especially with steels like S90V with a 61 RW
What about something like 20, or 22 dps? I'd be curious to see how a more obtuse edge angle would handle a staple.
As usual another insightful trial. Thanks for the effort!
Will you be doing a full s90v Manly Peak evaluation? I've been carrying my recently acquired one and am very impressed! The factory sharpening left a lot to be desired but was easily corrected and overall I find it a very practical knife for the money. It's nice to have a slim folding s90v knife with a thin grind and solid lock for such a reasonable price.
Joshua Briggs so far I agree, but I do want to give it more use before I commit to an opinion.
I don't think you mentioned and people understand how thin behind the edge the mantra, the peak and I'm sure, knowing the bear, his sport knife is also.
So that gives these knives a lot of points in my book vs the notion of how staples damage other people's knives in the real world.
+Michael Christy
I recently found your channel after becoming interested in knives and ordering my first “nice” pocketknife - a “Gent”, designed by Ferrum Forge and sold by Massdrop (S35V).
I’ve watched a few of your videos. It’s obvious that you have studied the science of steel alloys and how to get a great (and, I like how you described it - “healthy”) edge on a blade. I also enjoy your style of presentation.
For someone like myself who has no experience sharpening a knife, where would you suggest I start? I’d like to learn the skills I need to sharpen my knives properly.
How did you learn?
Is there a book you can recommend?
I am willing to spend some money on equipment I would need. But obviously I’m curious how much of an investment is needed.
Thanks for the work you invest in making these videos!
John Pifer
Don't know if the photos are to scale, but it looks like the bevel on the M4 knife is taller, as compared to BBB fixed blade, which might be a factor. I think we need to consider stock thickness and thickness behind the edge/bevel height, as well as angle (for a given thickness behind the bevel and bevel angle the bevel height is fixed, i.e. the base and sides of a triangle).
Abe the knives are at different thicknesses behind the edge, which is why the bevel sizes are different. The bevel angles are the same. The different thickness behind the edge would only matter in this kind of testing if the damage was enough that it moved onto the primary grind, which I don’t believe that it did. (Or not very far into the primary grind.)
@@michaelchristy4982 I'm not sure about that. I don't know if it's something that has been studied, but I can imagine that the bevel height may play a role. Essentially, it's having a larger or smaller wedge of the same angle. That might affect how vibrations travel/harmonics, and how much compressive load the wedge can take. Having thicker or more massive stock behind the edge may also be a larger reservoir for vibrational energy, or otherwise change how vibrations travel (possibly being weaker for certain harmonics, i.e. if it is less flexible). Perhaps there are some engineers or metallurgists who want to weight in.
Hi Michael, your "toughness test" was an actual edge stability test at low energy impact.
Dont relate it to toughness as such. Steel behaves differently at the very thin
sections than gross material (toughness). Forget steels like CPM-V4 or CPM-M4 being tough.
I know that people selling products / steels is where the information came from.
So its needed to take it accordingly. These steels are tough relative to their class/application.
Toughness in short blades is the least important property anyway.
Perhaps the thinnest knife behind the edge could behave as a spring
and absorb more energy than thicker geometries, despite identical
sharpeing angle so results may still not be relevevant.
Obviously there are much more variables to control but just with the same geometries
and high amount of trials you would already get a good results. Nice video and idea. )
I appreciate the real world testing. No one actually hammers their $200 folder through steel or only cuts paper. Staples are common impediments. Have you considered increasing the number of slices through staples between viewings? Possibly more hits could represents days or weeks worth of EDC between sharpenings. S90v surprises again!
Ryan Bryant too many hits would cause chaos on the edge. I was shooting for specific hits... you know, that mistake you make when you hit a staple and stop to stair at your knife for several minutes, just looking at what you’ve done. Lol, trying to replicate that situation.
What was the brand of the 3k diamond plate you said you used? Ketchworth it sounded like. I need a good diamond stone after my atoma and my dmt extra extra fine just isn't ideal because of the contamination of bigger diamond stones.
Paul Lonardo Ken Schwartz 3K Diamond plate.
@@michaelchristy4982 oh haha duh. Thanks! I just got the manix 2 4v, PPT S90V, and the K2 in 10v obviously. I Rmemeber your video on the k2 and always wanted one.
Paul Lonardo those are some nice models.
Great idea. Interesting results. From the microscope shots it looked to me like the 4v fared significantly better than the other 2, and that there was almost no difference between m4 and s90v. Maybe I missed it, but did you discuss the edge angle of these knives, or the impact different edge angles might have on the results i.e a more obtuse angle should be more resistant to chipping than a thinner angle. I know you usually sharpen to 30 inclusive but figured it may be worth mentioning.
chris pregent all were at 30 inclusive. Not sure if I highlighted that in the video. I was pushing to get this one done.
i knew that was a bbb knife before you even said it. i want to grab one
stlchevy95 you should. His knives are really nice.
Big brown bear really knows his stuff
I would kill for that BBB knife!
Mike, what is the grit on the Spyderco Ultra Fine bench stone ?? I can't find out anywhere ! Or what you believe it is ?!?
8K - 10K ??
Anthony Esposito according to Jende’s website, med 1200, fine 2K, UF 4K. However, I’ve seen other numbers. Why do you ask?
@@michaelchristy4982 just curious how high of a grit you were taking the blades up too !! I know your stropping on a much higher grit, but again I was just curious how high you were going with the actual stones !! I have a Chosera 3K (I think they're Naniwa Professionals now) that I've been finishing on !! I'm coming from the Straight Razor world and just recently started playing around with knifes !!
@@michaelchristy4982 might even see how my Suehiro Gokumyo 10K & 20K work out !! LOL !!! Probably total overkill !!!
Anthony Esposito keep in mind, I’m not polishing with the UF. I’m just bringing the sharpness up.
dig the look of that manly knife
Me too! I would like to get it. The blade profile shape and finish are great!
ssunfish Looks like a Spyderco Police with a FFG, so basically a Military.
Thickness behind the edge will make a major difference as will Rockwell hardness. I have a favorite little fixed blade knife in AEB-L hardened to 62.5 that chipped quite easily in use. Is AEB-L a steel lacking in toughness? No, it was a thinly ground knife with a very acute edge angle.
I applaud the attempt here, no matter the flaws. Even when everything is kept constant, your results may still be the same (depending on how thinly ground/sharpened the blades are).
The BBB custom knives are ground very thin. I'm not sure of the exact behind the edge measurements on these knives but I doubt his 4v custom was any thicker than the knife in M4 and it took less damage. My guess would be that it's actually ground thinner than the folder. I agree that ideally everything would be kept constant thickness wise for more accurate results but I don't think it had much influence on this test.
I have a question mike about cpm s110v and your the only person who’s advice I’m gonna take but I can get the knife to shave hair with no problem but I just can’t get it to whittle a hair no matter what way I try to sharpen it. I use straight diamond and finish with the kme lapping films
Joe Montini what do you use between the diamond and films?
I start with a 140 grit then to a 300 then to a 600 and finish with a 1500 grit then I start with a 9 micron lapping film and go all the way down to a .10 of a micron I try not to skip a step as u mention in your one video about s110v my edge is sharp but it doesn’t get that really crazy bite like yours do
Joe Montini with something like S110V, the Spyderco UF is somewhat critical for me. You should try throwing that into the mix between the diamond and the films. Ken Schwartz can cut them to fit a guided system if that’s what you’re using.
I figured that mike I will look into that thanks for your input man
Joe Montini no problem.
Hello hope all is well, I recently purchased a hap40 Endura I was trying to sharpen it all the way back to the heel and I did a great job on one side but on the other side I ended up laying it back and I kind of don't trust myself to fix it and fur to get the most out of the steel wasn't sure if you offer any kind of sharpening service I was looking at regrind there just awfully costly but I would definitely be willing to pay whatever you would charge thank you
Dean Grondin let’s move to email.
michaelchristy13@gmail.com
I've seen some testing on Spyderco 4V sprint runs and it was higher than 64hrc... Most of them around 66hrc really..
All the sprint runs I’ve seen have tested between 64-65. The highest I saw was a 65.6 I think. I might be off by .1 or .2
Marek Masar garbage that hard
Awesome.
The Ace thank you.
@@michaelchristy4982 this is going to make you roll your eyes, but you'd definitely see a more significant change in damage if you upped the ante on the damage. The problem is, toughness tests can get out of hand. There's no reason to destroy knives. Usually we find out how tough our blade is by a mistake being made, and the blade surviving/hold up well to said mistake. The more damaging the mistake, the more information we're given. I don't have any real advice for you, as far as what I would suggest. It was a good test. But if the level of impact (in theory) was increased, I'm sure we'd see a bigger difference between steels. I'm not talking about pure chopping, but just a mistake more significant than hitting a staple that wasn't even clamped in place by a staple gun.
I'm a religious follower and look forward to your next video.
The Ace I understand what you’re saying, but keep in mind, my goal to try to mimic the kind of mistakes that are made. Beyond that, the impact was pretty significant. I’m surprised the damage wasn’t worse. When you hear people say, “I think I hit a staple.”, it gives the idea that they’re not sure. With this, there was no mistaking it. I could feel it and hear it.
Leading up to this test, I even tried hammering the edges through staples, and the damage was about the same. (This was with 4V and M4, not with S90V.).
@@michaelchristy4982 I understand. I think I am biased because I work in an environment where everything around me is steel. So mistakes are big mistakes. This is why I value toughness. But most people in the online knife community own a ton of knives and only open letters/occasionally slice cardboard with them. They don't value toughness so I know I'll have to do any thorough testing on toughness myself.
did you mention the behind the edge thickness of each knife . would the thickness dissipate the energy to change the damage more or less?
off topic .what parameters are used to decide strops with wood or leather ?
dan michell I doubt the thickness behind the edge would matter unless the damage went into the primary grind, which in this case, it didn’t.
As far as strops are concerned, wood or leather can be decided by a lot of factors. I often use wood if I want a fresh stropping surface, because I usually only use wood once.
@@michaelchristy4982 thanks . are you concerned with contamination of the wood or is it deforming during the stropping phase in that you only use it once . is the wood a flatter surface compared to leather being softer?or is the leather very hard and still flat ?
dan michell the wood will eventually deform from applying more compound. You can go past one use, but the first use with any strop (short of maybe nano cloth) is always the best. Sometimes I’ll use the same piece repeatedly. It depends on the sharpening.
See everyone talks about m4 being tough. I think it is a little tougher than other high carbide steels but at 62 -64 it is only a little tougher 5han M390 at 60. Just my experience. I had some chipping just the other day in a griptillian in m4. I was cutting some very ridged cardboard, like so ridged I did it know it was actually cardboard. It was part of a cheap coat hanger. Also maybe manly knives is not getting a good yield of carbides after heat treatment. That last test you did with edge retention and also this test are kind of maybe implying that.
M4 chipped on the cardboard lining of a coat hanger?
Matthew Forrest I’m curious about how the M4 knife has been sharpened recently.
The Ace yeah it did, I needed the wire part of the hanger so I put the tip in and kind od cut it off the wire. After I finished I had several chips in the edge. Big enough that I had to go back to diamonds to get it out.
Michael Christy it is a shot show griptillian. So a limited edition with a black coating. I don’t carry it much because of the black coating but it was Halloween so 8 needed a black knife 😂. Point is I sharpened it initially 2 years ago. Since sharpening I e stropped it or put a micro bevel with a spyderco fine stone. But honestly it never needed to be sharpened cause it was never really used. I would strop it because I got new compounds from ken shwartz and wanted to see if I could get a better polish.
Matthew Forrest so you did put a micro bevel on it?
Красиво
Interesting stuff.
But i think it would have been better if the staples were fixed instead of just pressed through without bending the legs. Now the knives seem to take less damage and just pop the staples out.
Rutger Mulder does a staple gun bend the legs back? Not a stapler, but a staple gun.
They use special staplers for cardboard boxes that bend the staples. A stapler gun is not used for cardboard.
Rutger Mulder oh, you mean the big brass looking staples and the gun to go with them. I don’t have one of those. I figured a regular staple gun would be good because I could use it around the house as needed after the video... now I just need to find it.
Yeah the brass staples. That is the stuff i run into at work. They are sometimes hidden under tape. So when i saw you cutting the cardboard i noticed you sliced through it so easy. I don't know if it would make a big difference for the edge damage in the tests. But i thought if you bend the smaller stapler gun staples it would replicate it more. Just a thought.
When doing it right you'll get steel to widdle at 350 grit
skank hunt 48 bro, totally.
Hi, who is winner?
4v. But like he said the differences were fairly small especially between the 4v and m4.
What I think is relevant are micro bevels! What degree of micro bevel should be done to have no damage!!!! And another thing is look how thin those knives are and they did fine! U didn’t need a super thick zt to handle alil damage!
Jovonn Trujillo I agree about the thickness.
The maker of that 4V fixed blade sure cut corners on that finish huh 😉...JK
Michael Christy video!
(Puts family back in cage .. gives them Bucket of fish heads.. shuts the lights off.. closes door)
Cracks open beer...
SuperSteel Steve LOL.
Toughness over hardness for me any day.
RMFN that’s cool, but do you realize the hardest of the three knives showed the highest toughness?
Good, common-sense testing... thanks.
EverydayPatriot thanks. That’s what I was shooting for.
Just today I happened to watch this video, of a test of a chopper using S90V at 65HRC: th-cam.com/video/NiMxx1fCFBw/w-d-xo.html
I was surprised to find that S90V has quite considerable toughness at "ordinary" tasks.
Could have just been a difference in your sharpening. Arms tire ex. Plus you hold your stones when sharpening which is janky as hell. Try a better set up I would suggest and your results would be more reputable.
skank hunt 48 haha! Absolutely.
Skankhunt 48. What? Here’s an idea. You spend your own time and money, make your own videos documenting everything including sharpening your knives on whatever system you want and post your own results. Then we can all armchair quarterback your results and nitpick what you did or didn’t do.
Bought a staple gun and then immediately lost it in my house..... classic! Haha
christian johnson LoL, it happens. I’ve found it since the video.
Not a correct test. You should do much more cuts than 3... about 20 cuts would be good enough to see the real picture.
NSTD what’s that number based on?
@@michaelchristy4982 more numbers, more real picture. You did not make only one number right? If you dont want make many rounds, then you should exactly repeat all test conditions, like blade thickness behind the edge\power of movement\speed\angle\blade part spot\orientation of staple\power of staple connection and so on...
NSTD you didn’t answer my question. What’s the number 20 based on? Do you have a legitimate reason for throwing out that number, or did you just pull it out of your ass?
NSTD Then why don’t you spend your own time and money on the knives and video and tests. Then you can post your own results and we can all nitpick what you did and didn’t do. You know, like how 20 cuts wasn’t enough and you should have done 50. Or maybe 75 cuts, or better yet 100 cuts. They all were cut the same amount of times. So the results are what they are. Pulling a random number out your butt like 20 isn’t proving anything other than you weren’t happy about the results and your biased opinion towards a specific steel.
@@TheBigToe69 you guys both seems have special interest about what comes from the ass.
Knife people need to stop being such steel queens… my dads Boker is still doing fine, as is his old Case large hunting knife. Yeah, I’ll pay more for different blade steels, but… quit being such queens!!! And stop paying for whatever price they try to throw at us. People pay only what the market will bare… I think we’re getting beat about our heads with grail knives and then them always being unavailable and thus inflating the prices and then they throw other options at us at STEEP PRICES!!!