M390 carbide tearout? Delica ZDP vs Griptilian?

[Wowbagger]

I know this is a controversial topic, so going forward let's just act like it is a solidly confirmed fact on this thread.

Hahahahah
First off I didn't vote.
Second; which Griptillian ? ? ? Mine has M390 PS : oh I just saw Grip in S30V.
The M390 is stellar stuff. Carbide tear out ? ? ? I have had zero issues sharpening M390 or ZDP-189.
I did nothing special just use high end stones (Shapton Glass and DMT).
Seriously ? People have trouble with these two alloys with carbide tearout ?
I go polished 99% of the time and these were the two supersteels I had first and they have ALWAYS held up for like ever with cutting abrasive stuff, the edges have been effortless to get easily hair whittling.
I just don't see the concern.

I'm not nearly that impressed with S30V, S90V and S110V and I came to those well after the two alloys you mentioned.

All that said of the knives you mention I would go for the Delica in ZDP-189 for my own use but for other people I would recommend the M390 because it is less prone to chipping if the user isn't some what careful.

I'm not familiar with the Link. I could look it up but I'm just being lazy.

 

[tomhosang]

Lolol whatever man. Thats the dumbest thing ive heard. If steve made you come to this conclusion, then thats just not right.

Steve didn't make anyone come to any conclusions. He made a video on the subject and put it out for the world to interpret the results. Christy put a video out literally the next day calling his test BS and then had a VERY different result. It just seems odd that two very talented sharpeners using the same test medium (cardboard) came to such dramatically different results. People seem to get offended very easily in the knife community when the results of a test don't line up to what has been repeated over and over on the forums/YouTube. I think everyone needs to keep an open mind about ANY results that ANY tester gets. Now that there are so many testers out there, more and more results are being posted. Many of them are very similar and some are anomalies. It's very easy to sway results to prove your point through editing. Christy never shows the full duration of his cutting. Having Steve have the same results come up twice (1 being live) validates the test IMO. Christy did a video a long time ago on carbide tearout and said that it did NOT make any difference in use. Here we are, a year or so later and he's saying that it does (significantly too). I'm not trying to change anyone's mind on anything. It just seems awfully odd. His videos have been questionable at best lately (saying the Kapara in S30V held a hair whittling edge over a month in normal use with no stropping).

 

[Mo2]

Steve didn't make anyone come to any conclusions. He made a video on the subject and put it out for the world to interpret the results. Christy put a video out literally the next day calling his test BS and then had a VERY different result. It just seems odd that two very talented sharpeners using the same test medium (cardboard) came to such dramatically different results. People seem to get offended very easily in the knife community when the results of a test don't line up to what has been repeated over and over on the forums/YouTube. I think everyone needs to keep an open mind about ANY results that ANY tester gets. Now that there are so many testers out there, more and more results are being posted. Many of them are very similar and some are anomalies. It's very easy to sway results to prove your point through editing. Christy never shows the full duration of his cutting. Having Steve have the same results come up twice (1 being live) validates the test IMO. Christy did a video a long time ago on carbide tearout and said that it did NOT make any difference in use. Here we are, a year or so later and he's saying that it does (significantly too). I'm not trying to change anyone's mind on anything. It just seems awfully odd. His videos have been questionable at best lately (saying the Kapara in S30V held a hair whittling edge over a month in normal use with no stropping).

Drama.

1. Carbide tear out in sharpening is specific to high vanadium steels, with 3% or 4% vanadium often being the discussed threashhold after which it may happen.

Its always been said that 3-4% Vanadium is when diamonds often help over other abrasives in sharpening. Due to them making the job much faster and it becoming a lot longer on other stones. Due to the Vanadium being so hard in comparison. Not sure how that transitioned to carbide tear out. But its certainly possible.

 

[Banter 247]

Drama.


Its always been said that 3-4% Vanadium is when diamonds often help over other abrasives in sharpening. Due to them making the job much faster and it becoming a lot longer on other stones. Due to the Vanadium being so hard in comparison. Not sure how that transitioned to carbide tear out. But its certainly possible.

With regard to tear out, the link with diamond vs alumina has been that alumina cuts the matrix around the vanadium carbides, but some assert that it won’t cut the extremely hard vanadium carbides, themselves. Alumina is said to weaken the matrix, contributing to tear out.

That part aside, there is the matter of whether diamond is better for cutting/sharpening high vanadium steels than ceramics are. I use ceramics at the moment, but I’ll be the first to admit that diamond is a better way to go. Sometimes feels like an eternity setting a new edge angle on 220grit ceramic. More cutting power would be great. I’ll switch at some point.

 

[Mo2]

With regard to tear out, the link with diamond vs alumina has been that alumina cuts the matrix around the vanadium carbides, but some assert that it won’t cut the extremely hard vanadium carbides, themselves. Alumina is said to weaken the matrix, contributing to tear out.

That part aside, there is the matter of whether diamond is better for cutting/sharpening high vanadium steels than ceramics are. I use ceramics at the moment, but I’ll be the first to admit that diamond is a better way to go. Sometimes feels like an eternity setting a new edge angle on 220grit ceramic. More cutting power would be great. I’ll switch at some point.

Indeed. I remember this thread well...
https://www.bladeforums.com/threads/m390-and-cognates-rolling.1562908/#post-17955139


https://www.bladeforums.com/threads/m390-and-cognates-rolling.1562908/page-2#post-17963352

 

[lambertiana]

Whatever knife you choose, two things to consider:

1. High V alloys will burnish alumina stones because the V carbides are harder than Al2O3.
2. For general purpose use, 400-600 grit gives the longest-lasting edges. If you are cutting a lot of fibrous material (rope, cardboard) you may want to go on the coarser side. If you do a lot of woodwork you will want a lot finer finish.

 

[Mo2]

Whatever knife you choose, two things to consider:

1. High V alloys will burnish alumina stones because the V carbides are harder than Al2O3.
2. For general purpose use, 400-600 grit gives the longest-lasting edges. If you are cutting a lot of fibrous material (rope, cardboard) you may want to go on the coarser side. If you do a lot of woodwork you will want a lot finer finish.

How do you know coarse is always better than fine?

Have you seen the tests done that shows some steels are better finer than coarse when cutting rope. Cedric ada channel has a spreadsheet of these tests done.

Your right about it being different for what you're cutting ie wood, rope, cardboard, but it seems to vary depending on the steel as well when you look at the data.

When im cutting most things i prefer to cut with a more coarse grit. Reason being it is easier to cut. As it feels like the coarse edge is helping cut it faster and easier with pull through cuts. Where as a mirror is a more pressure as a push cut. But the longer lasting edge may go one way or another depending on factors.