Rockwell Hardness Tester

[jeffbird]

I will take your suggestions into consideration.

I need to modify my first comment. Testing in unaltered condition is important. However, so you do not have to buy an endless supply of knives, it would be ok to me as a reader if the blade is sent to you from someone else for testing as long as you inspect it and it is unaltered.

Once you earn some trust here, some folks here likely would send you some interesting things or mass market knives not in your results. Just note the source of the blade and condition new/used in a column or notes for consideration, especially for results out of the expected range.

 

[TaylorHardness]

I need to modify my first comment. Testing in new condition is important. It would be ok to me as a reader if the blade is sent to you from someone else for testing as long as you inspect it and it appears new and unaltered. Once you earn some trust, some folks here likely would send you some interesting things or mass market knives not in your results. Just note the source of the blade in a column or notes for consideration, especially for results out of the expected range.

This all sounds reasonable to me. I absolutely do inspect every blade tested. It’s a major part of my process. Inspecting for damage, flatness is verified on calibrated Mitutoyo calipers (I forget the exact model, but they’re good quality) on the test region to ensure the blade is parallel. Every blade is degreased as is necessary by industry standards.

I do think the unmodified part of your comment will be more important than the source of the blade itself, as long as it’s of course a legit blade. And not a clone. I’ll leave my thoughts on clones out of here, but I’ve been critical of them in lots of threads.

 

[Skylark427]

You buying them new in completely unaltered condition is a must have to remove any questions about changes after it leaves the manufacturer’s hands.

One friendly suggestion, change the title “Leader Board” and any talk about “scores” as the word choices create the impression that hardest is “the best” or most desirable trait. Different intended uses of a blade require different designs which need different steels with different hardness for optimum performance for the intended use. It is not a competition. You are reporting scientific test results.

My thin and hard Rex 121 skinning knife is optimized for that task as is a 10V. Another in 20cv at even lower hardness is my most used hunting knife out of thirty or more to choose from. A really big, but soft, Busse is my go for clearing brush and chopping sides of ribs off a pig’s spine. The Rex 121 would break in short order chopping bone. The Busse will not have great edge retention for skinning compared to the others. One is not better than the other. They are different tools for different tasks and best for their intended uses despite hardness being more than +/- 10 - 12 apart in hardness.

Having said that, your testing helps the buyer make better informed decisions about whether certain steels and blades match optimized results advertised by the maker.

So by all means, please keep up the work.

We're aware that different knives have different intended purposes based on hardness range. We're also aware, as I had pointed out previously, that just because a knife is measured at a specific hardness, doesn't necessarily mean it was heat treated optimally for knives to begin with either, as we won't ever know the specific heat treatment process for every company or knife we test. So that's even more variables.

The way SmashedLlama set up the site was more out of creative freedom and an interactive way to compare brands, steels, and hardness ranges across manufacturers. There's obviously a huge difference in a carbide replacement steel that's made to go to 68-70Rc and a higher shock resistant steel like L6 at 58-60Rc or a low carbide volume powder metallurgy steel like 3V at 61Rc.

That said, maybe "leaderboards" and the rankings weren't made to say necessarily that certain steels are better than others, it was more just how the creator thought to list everything out with the time he had to make the site, we didn't ask for his help, he willingly volunteered it one day just out of interest and to help us out. I'm still very grateful for the time he spent and his contributions.

That said, I do understand your point. Maybe there's a middle ground that would make more people happy. I'm not positive. But I've expressed several times that the hardness is just one factor of the knife and heat treatment, it isn't necessarily the entire story.

I do appreciate the contribution, and recommendations. We're open to anything beneficial to the project.

 

[TaylorHardness]

We're aware that different knives have different intended purposes based on hardness range. We're also aware, as I had pointed out previously, that just because a knife is measured at a specific hardness, doesn't necessarily mean it was heat treated optimally for knives to begin with either, as we won't ever know the specific heat treatment process for every company or knife we test. So that's even more variables.

The way SmashedLlama set up the site was more out of creative freedom and an interactive way to compare brands, steels, and hardness ranges across manufacturers. There's obviously a huge difference in a carbide replacement steel that's made to go to 68-70Rc and a higher shock resistant steel like L6 at 58-60Rc or a low carbide volume powder metallurgy steel like 3V at 61Rc.

That said, maybe "leaderboards" and the rankings weren't made to say necessarily that certain steels are better than others, it was more just how the creator thought to list everything out with the time he had to make the site, we didn't ask for his help, he willingly volunteered it one day just out of interest and to help us out. I'm still very grateful for the time he spent and his contributions.

That said, I do understand your point. Maybe there's a middle ground that would make more people happy. I'm not positive. But I've expressed several times that the hardness is just one factor of the knife and heat treatment, it isn't necessarily the entire story.

I do appreciate the contribution, and recommendations. We're open to anything beneficial to the project.

This is the way I read it. It doesn’t necessarily have to be the most serious thing in the world. The data is there, the testing was done properly, and the info is easy to sort through. That is what I personally care about. If we want to have a little mini game on the website, why not have some fun with it?

 

[jeffbird]

This is the way I read it. It doesn’t necessarily have to be the most serious thing in the world. The data is there, the testing was done properly, and the info is easy to sort through. That is what I personally care about. If we want to have a little mini game on the website, why not have some fun with it?

Guess it comes down to whether you want your work to be viewed as serious scientific testing or just social media click bait. This difference in impression may be one reason you received so many questions at the beginning of this thread.

 

[TaylorHardness]

Guess it comes down to whether you want your work to be viewed as serious scientific testing or just social media click bait. This difference in impression may be one reason you received so many questions at the beginning of this thread.

I understand where you’re coming from, but the data is all there, and the methods could not be any clearer. If it turns some people away, so be it. If a small nitpicked aspect of a fun website turns people away from it, then they were not there for the science and data aspect in the first place. All of the other Rockwell testing before us has been done with poor equipment and/or poor technique. If the one time a group of people are doing it properly decide to have a cool website, I fail to see where the issue is.

Edit: To be completely honest, as I typed this up I realized I care even less than I initially thought. I can say a steel is the greatest thing since sliced bread, and that’s an opinion. We are allowed to form our own opinions as far as I know. I think people are smart enough to separate facts from opinions on here.

Also, I initially ignored the back half of your comment. The reason I received so many questions was because someone the rest of the guys in here trust, misread a technical manual on our equipment. It was not inherently our fault in the slightest. That should be made perfectly clear at this point.

 

[Skylark427]

Guess it comes down to whether you want your work to be viewed as serious scientific testing or just social media click bait. This difference in impression may be one reason you received so many questions at the beginning of this thread.

I hear what your saying, but the website itself does allow a lot of interaction and comparisons, especially the graphs for ranges on certain steels from brands, that once enough samples are tested they will still reveal quite a bit of scientific data, even if it's just a plot of hardness results.

To be clear, it is still just hardness results, as stated. So there's still the variables of heat treatment and such for the actual knives used to reach those numbers. But it will give some people and idea of a range.

I'm open to suggestions, as I said. But I don't really think the "rankings" SmashedLlama made to really be anything beyond just his artistic representation of the website. It doesn't mean necessarily that some steels are bad results or not. You would need to break down the knife in question, it's intended use, then the steel being used to see the range and go from there. Some steels can't even go much past 60Rc in production for some applications(larger knives/heavy choppers/machetes) and still remain a good option.

But again, I see what your saying if your looking at it beyond a random buyer, but as a scientific database. I can see from a scientific viewpoint that it could come off differently.

 

[Maximumbob54]

I just really apprecieate something beyond the usual fun but obviously "bro science" when it comes to knife info. Watching someone cut through cardboard, rope, or whatever can be made to be entertaining if they are smart about it but it's a sample size of one, the complete opposite of a lab test, and stacking of human layers of differences. So this will be another interesting data point besides looking up catra test scores or the like. It's all entertaining but it's also a bit comforting having a little more evidence that it's not a blade made of cheese steel.

 

[TaylorHardness]

I just really apprecieate something beyond the usual fun but obviously "bro science" when it comes to knife info. Watching someone cut through cardboard, rope, or whatever can be made to be entertaining if they are smart about it but it's a sample size of one, the complete opposite of a lab test, and stacking of human layers of differences. So this will be another interesting data point besides looking up catra test scores or the like. It's all entertaining but it's also a bit comforting having a little more evidence that it's not a blade made of cheese steel.

Agreed. I’d have been ecstatic if I had access to legitimate Rockwell hardness data on an array of brands/steels when I began my knife collecting. I’d have made a lot of very different purchases than I did.

I have gone ahead and purchased several knives this morning. So far I have purchased a Remette Rhino in D2 steel, a Kizer Drop Bear in 14C28N, a Kizer Drop Bear in Nitro-V, a Vosteed Raccoon in 14C28N, a CJRB Pyrite in S90V, and a Demko AD-20.5 in D2. Still willing to purchase more knives if you guys have even more suggestions. I got a slamming deal on 5 of those in a bundle that a kind gentleman on Reddit offered me.

Oh just a sidenote, most of the knives I get recommended and purchase will probably be in the relative range of sub $300 or so. The vast majority of the knife community focuses on this range from what I’ve seen. The lower cost knives are of course easier to afford by a wider array of people. So this will play a factor in how I go about making purchased. Also me being a college student with bills to pay, and a fairly low income play a big part in this.

 

[Maximumbob54]

Demko AD-20.5 in D2.

I've read that the AD20.5 D2 is K110 which I also remember reading is just Euro D2 in a name brand label. So I'm super curious to see a "K110" comparison to the average (usually Chinese produced) D2.

 

[TaylorHardness]

I've read that the AD20.5 D2 is K110 which I also remember reading is just Euro D2 in a name brand label. So I'm super curious to see a "K110" comparison to the average (usually Chinese produced) D2.

Good to note, looking at their website they list both K110 as well as D2. I will list whatever is on the blade when I do the test on it.

Edit: listing what is on the blade is probably what I’ll do as a general rule of thumb. If anyone has anything to say on that end let me know, totally open to suggestions on this.

https://imgur.com/a/j3hHoeB

 

[jbmonkey]

im good with used knives tested that haven't been blade modified. as in regrinds done to them. also not ones that have been used to pick up red hot lava chunks....this has been done before by someone that used to be here......

I feel the ways y'all have defined the testing is good enough. I wouldn't call it marketing click bait stuff...its more science than most of us can do. so the data is good, least to me.

 

[Blues]

JB, I've submitted your name for consideration by the diplomatic corps. Pick me up something nice if you get assigned overseas.

 

[Skylark427]

I just really apprecieate something beyond the usual fun but obviously "bro science" when it comes to knife info. Watching someone cut through cardboard, rope, or whatever can be made to be entertaining if they are smart about it but it's a sample size of one, the complete opposite of a lab test, and stacking of human layers of differences. So this will be another interesting data point besides looking up catra test scores or the like. It's all entertaining but it's also a bit comforting having a little more evidence that it's not a blade made of cheese steel.

Oddly enough, I've also got controlled cut testing planned with HDPE and Kevlar rope, 3/4". My wife and I didn't do one run though, typically a minimum of 3 and potentially more. The basic premise is to start on the same knife platform (going to be the Mule for this because I've not got the money for that many customs this time around) correlate a beginning cut force with a beginning BESS score, determine around a range of force gained (say 15lbs+/-2) and correlate that to a BESS score (say 450+/- 50) and test the knives starting at 26° inclusive, 0.010" BTE(thinned) and see how all the steels perform in relation to each other (this time a minimum of 5 runs) then start lowering the angle to see when performance is no longer gained at that specific hardness, with that steel.

A secondary test utilizing just the BESS tester itself as the test method was also added out of curiosity of another user from another forum and me(isolating the apex only to see if results change) by using HDPE fishing line in the BESS PT50A holder instead of the standard media, and switch between two holders (one with the HDPE fishing line, one with the BESS media) to see is isolating just the apex makes a difference in the testing.

This is sort of a background project of mine I want to pick up again, I'm just very interested which steels at which hardness levels hold a stable edge for just pure cutting on abrasive material. I want to pick up where my late wife and I left off, after the burglary.

I agree though, one run with rope, with all the knives being different doesn't tell as much.

Sorry for the ramble. I'm glad you appreciate the database so far

 

[Skylark427]

im good with used knives tested that haven't been blade modified. as in regrinds done to them. also not ones that have been used to pick up red hot lava chunks....this has been done before by someone that used to be here......

I feel the ways y'all have defined the testing is good enough. I wouldn't call it marketing click bait stuff...its more science than most of us can do. so the data is good, least to me.

That's much appreciated. We definitely check all blades beyond just signs of modification/tempering. Moreso Taylor on the tampering, me mainly for flatness and modification if a knife is used(flatness if new).

 

[knarfeng]

Oddly enough, I've also got controlled cut testing planned with HDPE and Kevlar rope, 3/4". My wife and I didn't do one run though, typically a minimum of 3 and potentially more. The basic premise is to start on the same knife platform (going to be the Mule for this because I've not got the money for that many customs this time around) correlate a beginning cut force with a beginning BESS score, determine around a range of force gained (say 15lbs+/-2) and correlate that to a BESS score (say 450+/- 50) and test the knives starting at 26° inclusive, 0.010" BTE(thinned) and see how all the steels perform in relation to each other (this time a minimum of 5 runs) then start lowering the angle to see when performance is no longer gained at that specific hardness, with that steel.

A secondary test utilizing just the BESS tester itself as the test method was also added out of curiosity of another user from another forum and me(isolating the apex only to see if results change) by using HDPE fishing line in the BESS PT50A holder instead of the standard media, and switch between two holders (one with the HDPE fishing line, one with the BESS media) to see is isolating just the apex makes a difference in the testing.

This is sort of a background project of mine I want to pick up again, I'm just very interested whifh steels at which hardness levels hold a stable edge for just pure cutting on abrasive material. I want to pick up where my late wife and I left off, after the burglary.

I agree though, one run with rope, with all the knives being different doesn't tell as much.

Sorry for the ramble. I'm glad you appreciate the database so far

If you add controlled cutting of rope, I have some suggestions, having done quite a bit myself some years ago. (Aside from working to ASTM specs, I've also been a development engineer where I needed to develop my own test methods.)
1) Sharpen each blade using a system that sets the angle so that it's exactly the same angle on every knife.
2) Use diamonds or cubic boron nitride as the sharpening medium. You want to use a sharpening medium which is harder than the carbides in the steel for optimum performance of the sharpened blade.
3) If you are going to use slicing cuts rather than push cuts, mark out a specific length on the blade and keep the cut within that area, so that you are using the same amount of blade on every cut.
4) have a small gap on your cutting support surface and do each cut over that gap, so that the blade edge des not impact thw support. This eliminates variation due to the knife edge impacting the surface.

Note: Phil Wilson has said that manila rope is one of the best real world mediums for testing hunting knives. He says it's pretty close to an actual animal hide.

 

[SpyderPhreak]

Oddly enough, I've also got controlled cut testing planned with HDPE and Kevlar rope, 3/4". My wife and I didn't do one run though, typically a minimum of 3 and potentially more. The basic premise is to start on the same knife platform (going to be the Mule for this because I've not got the money for that many customs this time around) correlate a beginning cut force with a beginning BESS score, determine around a range of force gained (say 15lbs+/-2) and correlate that to a BESS score (say 450+/- 50) and test the knives starting at 26° inclusive, 0.010" BTE(thinned) and see how all the steels perform in relation to each other (this time a minimum of 5 runs) then start lowering the angle to see when performance is no longer gained at that specific hardness, with that steel.

A secondary test utilizing just the BESS tester itself as the test method was also added out of curiosity of another user from another forum and me(isolating the apex only to see if results change) by using HDPE fishing line in the BESS PT50A holder instead of the standard media, and switch between two holders (one with the HDPE fishing line, one with the BESS media) to see is isolating just the apex makes a difference in the testing.

This is sort of a background project of mine I want to pick up again, I'm just very interested which steels at which hardness levels hold a stable edge for just pure cutting on abrasive material. I want to pick up where my late wife and I left off, after the burglary.

I agree though, one run with rope, with all the knives being different doesn't tell as much.

Sorry for the ramble. I'm glad you appreciate the database so far

Sorta off topic, but I'm a big fisherman, so I'm curious; what HDPE line brand/type/weight are you using?

 

[Skylark427]

If you add controlled cutting of rope, I have some suggestions, having done quite a bit myself some years ago. (Aside from working to ASTM specs, I've also been a development engineer where I needed to develop my own test methods.)
1) Sharpen each blade using a system that sets the angle so that it's exactly the same angle on every knife.
2) Use diamonds or cubic boron nitride as the sharpening medium. You want to use a sharpening medium which is harder than the carbides in the steel for optimum performance of the sharpened blade.
3) If you are going to use slicing cuts rather than push cuts, mark out a specific length on the blade and keep the cut within that area, so that you are using the same amount of blade on every cut.
4) have a small gap on your cutting support surface and do each cut over that gap, so that the blade edge des not impact thw support. This eliminates variation due to the knife edge impacting the surface.

Note: Phil Wilson has said that manila rope is one of the best real world mediums for testing hunting knives. He says it's pretty close to an actual animal hide.

Well this wouldn't be part of the website, this is just mainly to continue where me and my late wife left off.

So far I've got 1-3 covered, I use the Edge Pro Beveltech, which I've found the best for my needs with how low the angles go (5°~ per side on sone knives, then subtract half the primary bevel if flat ground). It's so for been incredibly accurate on my goniometer. I use either Venev Orion or the Edge Pro bonded diamond stones.

I haven't decided yet if I was going to do a push, a slice, or both. Just because I'm interested in the differences between them at very low angles (my primary goal).

I hadn't thought of a fixture with a gap, in the past we used very small silicone mats made for protection of material when machining/forming or a chance of a surface getting marred. I forget the exact material, but the blade hit the mats, without blunting on the scale surface.

I was also thinking of manila rope as a secondary set of testing, as I'm also very familiar with that Phil Wilson quote (I had an S110V blade from him before the robbery, his knives are beautiful).

Thank you for the tips it's greatly appreciated. I want it to be as controlled as possible, which means even blinding the results to the best if my abilities to eliminate any possibility of observation bias. This has been something I've been wanting to continue for a while now, one in memory of my wife, and two to see which steels are "stable" at what geometries for just pure abrasive cutting. All our original data was lost during the robbery(as was everything in the house), so it's starting from scratch again. With the Mule being the main platform, I'll have to see if some custom makers are willing to make knives in certain steels with a blade similar (close as possible) to get steels at hardness ranges they didn't offer, or just those steels in general that weren't offered.

I really do appreciate it. Anything further you can think to add, I'm all ears

 

[Skylark427]

Sorta off topic, but I'm a big fisherman, so I'm curious; what HDPE line brand/type/weight are you using?

Actually haven't decided yet. This was just a conversation between me and another user who were curious if isolation of just the apex could potentially change the results for wear resistance and/or which steels performed the best at very low angles(think something like shaving). You have a brand in mind that'd roughly fit the BESS PT50A tester holder (0.009" thread, but it can hold up to roughly 0.025")?

Edit: It would probably need to be a lower weight one, seeing as the BESS PT50A maxes out at 1000 grams I believe, but I get the knives to around 50-60 BESS as the starting range.

 

[knarfeng]

in the past we used very small silicone mats made for protection of material when machining/forming or a chance of a surface getting marred. I forget the exact material, but the blade hit the mats, without blunting on the scale surface.

Silicone would do.

If you put the rope under slight tension when cutting, the fibers will pull away from the blade when cut. That elimiates the effects of differing blade shapes if you just want to test the steel, rather than the knife overall.