Apex Stability

[video]http://www.youtube.com/watch?v=Q5NAPoBaDmM&feature=youtu.be[/video]

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It's not Cliff, its Dr Stamp
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cKc,
Yes, exactly! The first time I zero ground a knife, applied a micro-bevel, the apex kept collapsing. Cliff explained to me that I needed a little more than a micro-bevel to stabilize the apex, like this:
[www.youtube.com]
and:
[www.youtube.com]

I also have notice a similar thing with the +30° DPS microbevels. I can get them very steep with-out any noticeable loss of sharpness, it will still pass a HHT 3/4. I am not sure why or what is going on with the extreme apex geometries, Cliff played with them a little with the Rex 121 knife he had.

edit:
With the 154CM on the Mini-Grip, i have had micro-chipping with use on angles <15° DPS. I believe this is because of the carbide volume, and I had the same issue with D2.

"I am still discussing issues of steels and performance at this stage." -- Cliff Stamp, May his memory be a blessing
"Life is GOOD", -- Stefan_Wolf, May His Memory Be A Blessing
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Edited 1 time(s). Last edit at 05/12/2020 06:39PM by jasonstone20.

And i like my comment on that video.. lol..

Quote
KnivesAndStuff
All I heard was "The convex bit makes it thinner, cut better, and more durable against damage"

you can cut hair on a highly polished 90 corner if its refined properly because the thickness of the hair is so small compared to the edge. doesn't face resistance to going in.

the slideshow visualizes the extra meat, which you can then apply to my rigidity chart to work out, strength, vs agility of the knife and find the balance you want.
One of my older videos explaining different ways to grind convex, this was covering swords and large blades, but it applies to any size knife
[video]http://www.youtube.com/watch?v=1xxf5_0djvE&feature=youtu.be[/video]

if you look at all my early knives, they were either "convex scandi" but in 7-8dps ranges that finalized in around 12dps edges, or they were full height convex that transitioned into an intermediary convex bevel, and then the final micro bevel (true micro).. because all my early knives were hard use, high performance cutting outdoor knives..

all my knives in the later years before i finished were focusing on my experiments with bleeding-edge thin knives that have just enough durability..

whats happening at the apex, is the most critical part of the knife, but the least understood.
this video is a great example of where apex matters, when you compare a thin knife with the overbuild apex as i described at the start of the video, vs a knife that is heavily overbuilt spine, with an extremely refined apex, that still has a lot of support

[video]http://www.youtube.com/watch?v=yYTqQMAUIcI[/video]

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

cKc,
Yeah, good stuff there. I am still kicking myself for not getting a hold of one of your blades.

"I am still discussing issues of steels and performance at this stage." -- Cliff Stamp, May his memory be a blessing
"Life is GOOD", -- Stefan_Wolf, May His Memory Be A Blessing
WordPress YouTube Facebook Patreon Locals Instagram Twitter

Quote
jasonstone20
I also have notice a similar thing with the +30° DPS microbevels. I can get them very steep with-out any noticeable loss of sharpness, it will still pass a HHT 3/4. I am not sure why or what is going on with the extreme apex geometries, Cliff played with them a little with the Rex 121 knife he had.

in regards to the higher carbide steels, its a simple matter to work out the size of the Avg Carbide cluster.. then add a buffer of 25% to that size to ensure that you have steel surrounding it.. then work out the appropriate apex angle to best support that carbide cluster.
the secret is to ensure that once you have that angle, dont keep it going more than you need to..



if you can, you are better to have an apex angle that supports the carbide better, but keep it as small as you can to do the job before dropping the angle.


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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
jasonstone20
cKc,
Yeah, good stuff there. I am still kicking myself for not getting a hold of one of your blades.

Cliff has a number of micro hikers that were sent for testing.. when the current issues settle ask him to send one to try out.

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Related to Apex Stability. Not sure if Cliff ever got better conclusions to the Rex121, as he indicated that as shown in the image above, on his rex121 the carbide clusters were not improved in edge retention by increasing apex angle,
[video]http://www.youtube.com/watch?v=7JEp5h_V580[/video]

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

cKc,
Yes, that was the video I couldn't find, and the topic I was thinking of. Not sure why that happened, and if it was specific to Rex 121.

"I am still discussing issues of steels and performance at this stage." -- Cliff Stamp, May his memory be a blessing
"Life is GOOD", -- Stefan_Wolf, May His Memory Be A Blessing
WordPress YouTube Facebook Patreon Locals Instagram Twitter

What i think may be happening with Rex121 is that unless you are sharpening the apex with perfectly clean diamond that can shave the carbide into an edge without grabbing, fracturing or tearing it out, then you never get a real apex. just a cruchy jagged mess. need a microscope i guess

----------------------------------------------------------------------
It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
cKc
in regards to the higher carbide steels, its a simple matter to work out the size of the Avg Carbide cluster.. then add a buffer of 25% to that size to ensure that you have steel surrounding it.. then work out the appropriate apex angle to best support that carbide cluster.
the secret is to ensure that once you have that angle, dont keep it going more than you need to..

if you can, you are better to have an apex angle that supports the carbide better, but keep it as small as you can to do the job before dropping the angle.

Or simply go by carbide volume as per roman landes?

thread 7,68985 V-Stick Sharpening Angle Formula
source https://github.com/jasonstone20/VStickAngle/
calculator/spreadsheet https://output.jsbin.com/xelazehazo
references
https://knifesteelnerds.com/2018/08/27/what-is-edge-stability/




PRINTABLE https://knifesteelnerds.com/wp-content/uploads/2018/08/schneiden.pdf



maybe do some measuring here
https://knifesteelnerds.com/2019/05/26/new-micrographs-of-42-knife-steels/

____
Thanks
I don't mow

Quote
cKc
https://docs.google.com/spreadsheets/d/e/2PACX-1vR9mss7mkelFeOlbn57qpTCF8fAABUUBFZEIWH_kJV81v4pgf41O86cTbIcTayICmkFElpHajV0-mF0/pubhtml#

Hi,
I'm getting a bunch of "#NAME?" in the spreadsheet ... something about the cell type no being numeric ...
anyway I replicated it in
https://output.jsbin.com/yutohabeku
seems to match video
switched from jsfiddle cause it got clumsy

____
Thanks
I don't mow

Yeah. That seems to be saying the same thing with pictures.
.
the real question is if it actually does make a difference, Or if the real issue is sharpening these steels in a way that doesn't ruin the edge during the process of sharpening.

even with a bigger angle, you dont know where the carbides are sitting in relation to the apex you are forming. if its sticking out 50% and you are sharpening with something that will tear it out rather than cut it, then its going to be hard to form a lasting apex.

I dont know.. I have very little experience with anything more than S30v etc.. they just dont hold my interest highly because they dont have the properties i like in a knife.

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
ShaperAndMower

Quote
cKc
in regards to the higher carbide steels, its a simple matter to work out the size of the Avg Carbide cluster.. then add a buffer of 25% to that size to ensure that you have steel surrounding it.. then work out the appropriate apex angle to best support that carbide cluster.
the secret is to ensure that once you have that angle, dont keep it going more than you need to..

if you can, you are better to have an apex angle that supports the carbide better, but keep it as small as you can to do the job before dropping the angle.

Or simply go by carbide volume as per roman landes?

thanks for the references. it's a good read with good diagrams.. and yes. it's basically saying the same thing I'm saying with a lot more detail and perhaps better wording.. but the main part I was trying to convey is the last portion of my quoted text.

the problem is that people will make the edge 60degrees, but then continue this for an entire large bevel to 0.02 or 0.03" often enough, where in reality, it only needs to be that thick for a very small portion of that to get the required size.

What I don't get, and maybe I just haven't seen or read it, is that knowing these things are important to edge stability, and some edges can take 10degrees cutting paper, and some need 30 degrees, or 50 degrees to get the most stable edge,
surely it makes more sense when doing comparative cartra testing to set up each steel based on the expected most desirable benefits of the steel and then see how each one does.

Larrin's recent test took them all to 0.01" and 15dps which seems thin.. but not when we know AEBL would perform at 0.003" and 15dps and this could have altered its performance tremendously. and then i wonder.. some of the higher carbide ones.. perhaps 15dps is lower than ideal.. i wonder if they would perform worse or better from increasing the edge angle..
instead of a high carbide one being 0.01" and 15dps, would it have preferred 0.005" and 25dps.

I'm just speculating because it's interesting. i certainly can't go and test this myself and find out. one day someone will, or maybe they already have and a reference will be found.

----------------------------------------------------------------------
It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
ShaperAndMower

Quote
cKc
https://docs.google.com/spreadsheets/d/e/2PACX-1vR9mss7mkelFeOlbn57qpTCF8fAABUUBFZEIWH_kJV81v4pgf41O86cTbIcTayICmkFElpHajV0-mF0/pubhtml#

Hi,
I'm getting a bunch of "#NAME?" in the spreadsheet ... something about the cell type no being numeric ...
anyway I replicated it in
https://output.jsbin.com/yutohabeku
seems to match video
switched from jsfiddle cause it got clumsy

Huh.. me too now.. need to check what happend

----------------------------------------------------------------------
It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Super weird, but the live publishing of the SpreadSheet is seperate from the sheets javascript which has to be republished manually. lol.

works now. i'd also changed it from 130% to 1.3 as it seems easier to follow..

35 times more is better than 3500%

thats a nice little javascript output

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

ShaperAndMower,
I was wondering something, and maybe I should ask Roman Landes, but if you look at the chart, AEB-L is in the smallest carbide group, so the angle should be 16°-25° Inclusive, but in the quote on Cliff's Reference Page, AEB-L is a Class II steel, and the angle starts at 12.5° DPS. What do you think? I have been running AEB-L at 8°-10° DPS/16°-20° Inclusive and having good results.

"I am still discussing issues of steels and performance at this stage." -- Cliff Stamp, May his memory be a blessing
"Life is GOOD", -- Stefan_Wolf, May His Memory Be A Blessing
WordPress YouTube Facebook Patreon Locals Instagram Twitter

Quote
jasonstone20
ShaperAndMower,
I was wondering something, and maybe I should ask Roman Landes, but if you look at the chart, AEB-L is in the smallest carbide group, so the angle should be 16°-25° Inclusive, but in the quote on Cliff's Reference Page, AEB-L is a Class II steel, and the angle starts at 12.5° DPS. What do you think? I have been running AEB-L at 8°-10° DPS/16°-20° Inclusive and having good results.

Hi
I think things man, things!

I vaguelly recalls a mention of whatever "Cliff's Reference Page" having different classification from landes ...
and that there is overlap in both ways of classifying
but I can't be arsed to look for it
the website is always timing out on me,
and the server doesn't seem to be doing dates/caching properly
( every page is timestamped today always -- nonsense)
and my notes taking ability is whack
update: well there you go
https://cliffstamp.beyondt01micron.com/knives/reviews/cardboard.html
seems more emphasis on hardness not merely carbide volume ...
which might be the same or different as Roman Landes way of classifying



Regarding the charts
In the Roman Landes diagram i linked, i think it says AEB-L has 5% carbide volume


knifesteelnerds.com/2019/03/04/all-about-aeb-l/
After heat treatment AEB-L has around 4-6% chromium carbide.


knifesteelnerds.com/2018/11/19/steel-edge-retention/
Here are images of AEB-L (~6% carbide volume) and CPM-154 (~17% carbide volume)


So there you go, boundaries are always fuzzy
I think I thought of this before but ,
maybe multiple entries for AEB-L are in order for those javascript charts

https://output.jsbin.com/hibupiheno

	idOut('id-out-stability', 
        volume > 15
        ? '20°-30°dps'
        : volume > 5
          ? '12.5°-20°dps'
          : '8°-12.5°dps' 
    );

AEB-L 4 0 0 0 0 0 0 4.0% 8°-12.5°dps 302
AEB-L 5 0 0 0 0 0 0 5.0% 8°-12.5°dps 313
AEB-L 6 0 0 0 0 0 0 6.0% 12.5°-20°dps 324


2% chromium carbides difference doesn't appear to account for this

knifesteelnerds.com/2020/05/01/testing-the-edge-retention-of-48-knife-steels/
AEB-L actually did better than I thought despite being near the bottom of the chart. A previous CATRA test we did comparing 154CM and AEB-L found the AEB-L to be about half of the 154CM, but in these tests the AEB-L was closer to 75% of CPM-154. Using the prediction equation based on carbide content always showed AEB-L being better than what was measured but I assumed some other factor was in play. Instead, these tests confirmed that the AEB-L performs as expected based on its chromium carbide content and the steel does relatively well given its good toughness.


____
Thanks
I don't mow

Quote
cKc
Super weird, but the live publishing of the SpreadSheet is seperate from the sheets javascript which has to be republished manually. lol.

works now. i'd also changed it from 130% to 1.3 as it seems easier to follow..

35 times more is better than 3500%

thats a nice little javascript output

Hmm ...I'm not seeing a change
update: output.jsbin.com/pujumetaha

____
Thanks
I don't mow

there is something sketch with google.. its prob cached the bad one on your computer. it did it to me too your javascript is working fine. just needds a style sheet.

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
cKc
there is something sketch with google.. its prob cached the bad one on your computer. it did it to me too

Sketchy indeed.
its not just my browser
or my computer,
or my network

Now I occasionally get
Loading...
in some browsers
before it goes back to
#NAME?


These shows the same
[www.browserling.com]
[www.site-shot.com]
[web-capture.net]

this one is not cooperating
[browsershots.org]

Quote
cKc
just needds a style sheet.

To do what?
you can always fork it

____
Thanks
I don't mow

Clearly their publish feature with javascript has issues then.
even when i open the file to edit sometimes its all bad, then it fixes itself.

Forking, fork it all..

Quote
ShaperAndMower

Quote
cKc
there is something sketch with google.. its prob cached the bad one on your computer. it did it to me too

Sketchy indeed.
its not just my browser
or my computer,
or my network

Now I occasionally get
Loading...
in some browsers
before it goes back to
#NAME?


These shows the same
[www.browserling.com]
[www.site-shot.com]
[web-capture.net]

this one is not cooperating
[browsershots.org]

Quote
cKc
just needds a style sheet.

To do what?
you can always fork it

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

styled

havent really used that site before. so here is a link i think.

its amazing how useful so many of the online facilities are these days.

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It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

I'm not the brightest person out there, so that crazy thickness calculation was very confusing to me. I thought the model must be more complicated than it really was, lol. Also, I've not used this site before (And I don't have any experience with JS or HTML). Maybe someone can check if this link works for them.

dtan function

works

Quote
mindsmirror
I'm not the brightest person out there, so that crazy thickness calculation was very confusing to me. I thought the model must be more complicated than it really was, lol. Also, I've not used this site before (And I don't have any experience with JS or HTML). Maybe someone can check if this link works for them.

dtan function

so annoying when someone finished school less that 5 years ago and remembers their math

Quote



function dtan(deg) {
return Math.tan(deg * Math.PI / 180) ;
}

----------------------------------------------------------------------
It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen

Quote
cKc
so annoying when someone finished school less that 5 years ago and remembers their math

Honestly I thought there was some odd thing about the model that I was missing which required the use of the "law of sines" or whatever it's called. I thought to myself, "Man I must be even dumber than I thought. Maybe I really am the kind of guy who would put lemon juice on his face to become invisible to security cameras."

Quote
mindsmirror

Quote
cKc
so annoying when someone finished school less that 5 years ago and remembers their math

Honestly I thought there was some odd thing about the model that I was missing which required the use of the "law of sines" or whatever it's called. I thought to myself, "Man I must be even dumber than I thought. Maybe I really am the kind of guy who would put lemon juice on his face to become invisible to security cameras."

Yup,
you assume this dog has actual knowledge in place of search-fu

if you wanna label it DPS i think it should start at 5 degrees

svg visual on a thousand inch five-micron-grid 1dps8dps12dps20dps30dps
jsbin.com/yegulakeko/1/edit?output
using css tricks for alternating row/col colors
and mouseover popup to show angle/angle
click on the chart to update the form input calculator on top of chart
jsbin.com/yegulakeko/1/edit?output#id-cKc
output.jsbin.com/yegulakeko/1#id-cKc

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Thanks
I don't mow

Nice work.

----------------------------------------------------------------------
It's not Cliff, its Dr Stamp
#kebabstickcut, it's a thing - make it happen