HD Benchmade S30V (c. 2008 or '09) chipping on light cutting

I have sharpened the plain part of the edge, and I find it interesting, but not surprising, that the serrations exhibit the same chipping problem:




[instagram.com]

This is just from light cutting, food prep, food packaging ect. It only took one sharpening on the plain edge to fix the problem, but it can easily be seen why someone would have a misconception of the performance of the knife, straight out of the box.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser



Edited 1 time(s). Last edit at 11/24/2015 10:23AM by jasonstone20.

Sorry, I can't get the image to embed properly, but the same link is just below the image.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Lately, I've been having trouble getting the tips of knives sharp...all of them production knives, and I'm wondering if that steel toward the thinner tip, at the edge, isn't compromised. I don't normally have a problem with this...if anything the opposite.

But at any rate, like you said it is easy to see how people could get frustrated / upset by these types of things.

_______________________________________________________________________________________________

Always in search of a good choppa'

Collin-
I have the same issue sometimes with the tips of knives, and there are a few factors that cause issues. The changes in thickness, angle and the tips of knives are one of the places that are easily damaged during power grinding and sharpening. I usually just spot sharpen the tips, from the beginning of the curve to the end of the tip, because I have found that if I try to sharpen it at the smae time I do the main part of the blade I end up grinding or rounding off the tip, or getting a massive burr, or all of the above. If I just go over it lightly while sharpening, and then spot sharpen later, I have better results, and the tip stays instant more often.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Thta's what I've taken to doing as well Jason. Spot sharpening once I have done the rest of the edge Sometimes though I still haven't had great success, even when being very careful with the angle, because as you've noted it is easy to mess up, especially if the tip thickens a lot.

_______________________________________________________________________________________________

Always in search of a good choppa'

Image :



You can dig it out using some kind of debugger or any inspect tool, however you can also use this script : [myword.jeffreykishner.com]

Cliff-
Thank you!

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Colin,

The mass of the steel is much lower in the tip hence it will over heat much faster. As well, the angles often change significantly in the tip and the blade thickens faster.

Thank you cliff, that's what I suspected was happening...it has mainly been on folders too with thin stock and fine points.

_______________________________________________________________________________________________

Always in search of a good choppa'

I have a Benchmade s30v blade I was considering making a thread about. It also blunts by chipping even after many sharpenings. I did find it to be 61rc, FWIW. It makes it a poor performer on cardboard with the thinner edge I run on it, but also keeps its edge for a very long time with very light use. I didn't sharpen it for a year, and for 6 months it stayed extremely sharp due to infrequent light use.

My next step will be to see if steepening the edge angles above (the current)15dps will slow the chipping on cardboard, though I am not sure if it will be worth the tradeoff in 'bite' it has currently when sharp.

It is an old or new knife? Do other knives not chip on the same cardboard?

It is older. I would guess about 5-6 years old. I only tested it against 2 other blades, checking out my heat treat on cpm154 and A2, neither chipped. The A2 blunted, the CPM154 blunted faster. I don't remember, but the CPM may have had a thicker edge, as the A2 was .07" at the edge, and I think the 154 was twice that.

I taped all but 1 inch of the edge, and pushcut cardboard at roughly 90*. The Benchmade came to a hard stop because it would chip slightly, then grab material, which would put the brakes on while cutting. A portion of the edge would have still cut, but the chipping portion worked like a parachute. Did 2 or 3 runs, it was a couple years ago.

This inspired me to sharpen the chip's out of the serrations. The metal flaked off when ground, like dry skin. I haven't seen that happen before. But in less than 3pps, the edge came back, not difficult to sharpen at all, like you'd suspect from this type of steel. No difficulty apexing or anything.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

How does it work in general?

Quote
CliffStamp
How does it work in general?

If this was to me, I would say that it works poorly. I carry the knife because of the looks and ergos, but if you knew nothing about it you would assume it was cheap stainless; hard to sharpen, can't hold an edge, etc. It did corrode badly when in a humid, cool basement for a while. It will hold an edge, just not an extremely sharp one. You can cut cardboard, sharpen pencils, etc., it just seems to have a large initial drop in sharpness. It will take a pretty decent edge, and it doesn't relax over time.

I keep debating trying to soften it up 1pt in hardness to see if it helps, but haven't messed with it yet. It doesn't burr much at all, I get more from the Spyderco s30v. It may be the next step if changing sharpening angles doesn't help.



Edited 1 time(s). Last edit at 01/24/2016 12:32AM by Any Cal..

Quote
Any Cal.


I keep debating trying to soften it up 1pt in hardness to see if it helps...

In general (very general), dropping one point in hardness won't resolve that type of problem because gaining 1 point in hardness doesn't tend to cause it. If the steel is chipping badly on light work it generally means something similar to :

-the aus-grain was blown
-the steel was severely over heated
-the quenching was so severe it micro-cracked the martensite

and similar issues.

Now could a further draw help it? Well it won't make the fracture worse, in general, but it isn't that likely to completely resolve it.

Have you tried contacting Benchmade?

I thought about this for quite a while.

I know that Benchmade builds using prehard stock, so wouldn't expect a plate to quench fast enough to really screw up...

Their grinding process is wet, so not really an overheating thing.

Almost wonder if it was an issue with the blade profiling HAZ.

Anyway, I just called them, I have to send it in to make any headway. The good news is that I should be able to buy a new 9051 blade at the same time!

Anycal-
Interesting. Thank you for the update. My knife blade seems to have stabilized, but I did have a 154cm Tanto Griptillian that was giving me issues, that seems to have gone away also. I think they changed something in their manufacturing that was for the better a few years ago.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Hmm video I've seen on the YouTube showed them sharpening dry by hand so the wet grinding isn't related to the sharpening. I have one s30v Benchmade that was similar brand new but after regrind has been a phenomenal knife for the last 7 years. I don't think buffing and dry grinds do the steel favours

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[data.gearbastion.com]
KnivesAndStuff (YoutTube)

cKc-
That's the same that happened to mine, it performs great now.

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Correct, the wet grind is how they do the bevels. Would have to double check, but I am pretty sure they sharpen on a 2x72 dry.

Shoot, I just sent 4 knives off, and forgot to put that one in there... I think I used it to cut down the shipping label Maybe when I get the other one back I will have a buddy long enough to send this one off.

cKc-
Here's the video from Benchmade's website, I think that this might be a LiveSharp sharpening service, it kind of hints ay it in the description.

[youtu.be]

"I am still discussing issues of steels and performance at this stage."
--Cliff Stamp

"Cause geometry cuts, .....steel determines the level and the duration"
--Roman Landes

"But in general, I'm all about high performance, Ergos, safety. That's why I've been accused of 'designing in the dark' "
--Sal Glesser

Yes.. thats the one I've seen before I think.

its impossible to tell how fast or slow the burr king is running, but even moderately slowly, without water, that could be enough to have a problem depending on how light fingered the person is.

of course that nice buffing will remove any signs of foul play if they were there.

they do get them sharp to the paper test.

on a side note.. this is one thing where I go with Bark River. I never grind edge down.. always edge up (belt, not buffer). I have never ever cut a belt, and the advantage is that you can see what you are cutting, and also less prone to getting the angle wrong or lopsided because you can see the angle better.

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[data.gearbastion.com]
KnivesAndStuff (YoutTube)