Why did my s30v chip?

O

Omega Leather Works

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Jun 13, 2007
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I'm at work right now and I brought along my Spyderco native for the first time. One of the tasks I have is cutting open boxes of salt bricks. The provided knife or razor is always dangerously dull, so I figured I'd give my s30v a workout.

The edge is a polished 34° inclusive. I zipped through the tops of two boxes then noticed some small chipping on the belly. I'm rather surprised and am wondering if you think this is normal. This is a native from Walmart bought several years ago.

Am I being naive? I figured s30v was much, much harder/tougher than that. As far as I can tell I never even hit one of the salt blocks, but even if I had I would have expected more.

Is my vg10 Endura better suited for this? I'm not going to try the 154cm Rift.

Thanks
 
Pictures or more technical descriptions would be nice. "Chipping" is a pretty broad statement, and without any descriptions could encompass anything from minor rolls/dents/tears to actual major chips.
 
The edge could just be rolling, which s30v is actually known for. While s30v is a tough steel it's been known to roll or chip. Though I don't have any problems with mine, but I am a little anal with my knives even when I use them hard lol.

It may be normal.
I had a Native at the same edge degree and didn't have any issues.
 
like others have said s30v is known to roll and chip , I heard somewhere it will actually break before it bends, dunno if thats true or not, pics would also help a lot , personally I've had some s30v blades taken to rather low angles and never had a chip , had a few rolls but never a chip, It seems though you know what your doing when you sharpen , so just sharpen it out, put a more obtuse edge on it, and try again.
 
Allen R. said:
like others have said s30v is known to roll and chip , I heard somewhere it will actually break before it bends, dunno if thats true or not, pics would also help a lot , personally I've had some s30v blades taken to rather low angles and never had a chip , had a few rolls but never a chip, It seems though you know what your doing when you sharpen , so just sharpen it out, put a more obtuse edge on it, and try again.
Click to expand...

Paul bos' S30v tends to break before it rolls.
CRK's S30v can do either. Roll or nick. S35vn tends to roll more than not.
 
Its not normal, and I would use a plain box cutter that uses razor blades. Would work much better, razor blades are cheap, and are easy to replace.
 
Mind posting a picture?

How long have you had the knife?

How many times have you sharpened it?

"Early on the edge is likely weakened due to power sharpening from the factory. If it keeps rolling on such work after sharpening then it could indicate a bit of a problem."
 
Thanks guys. This is all pretty much in line with what I am thinking.

Um... Just to clarify a few things... I'm actually sitting in the break room right now and can't take a pic. Knives are strictly prohibited. Shhh! ;) So let my incredibly imaginative mind paint you a picture... Tiny, tiny scallops. Done. Crystal Clear now? :D

The knife has been sharpened probably 3 or 4 times, the reprofiling done with a Lansky system, then the latest edge done with my edge pro.

I'm sure I'm forgetting to address something but my battery is dying. :o

Stupid phone. And work. And salt. :(
 
It could possibly be from the smaller particles of the salt brick stuck onto the cardboard box?

I think you're giving the entusiast knife steels in general too much credit. They still gotta come to a very fine edge and they will take damage.
 
Salt brick. Might as well be silica (sand). Just about the worst material for knife edges.
Use a razor blade utility knife.

Thanks to Ken44 and 100eyes. I agree with both of them.
 
Hrm... Well that's that I guess. Pretty weenie though if you ask me. I just have this sneaky suspicion that my Opinel would have taken it in stride. It really wasn't a demanding job. That and after inspecting the Dexter Russell junk that they give us which has no damage I'm just... eh I dunno... Not impressed. The Dex has a very obtuse edge though so there's that...

So we'll see how the Opi does tomorrow. :)
 
Box cutter blades are made from really thin stock and as a disposable blade chipping isn't a problem.
An Opinel isn't a box cutter but is also ground very thin, and they are cheap enough to almost be considered disposable.
These are tough acts to follow with a knife designed to last.
 
It sounds like your knife came into contact with the salt block inside the box. Those things are as hard as a rock.
 
I have my para 2 at 17 degrees, a very thin edge and I only have problems with it rolling, but for me its always due to the wire edge I've been told S30V is known for, which would explain the easy rolling. After a little use and a few stroppings I get the last bit of the wire edge off. Then it stays sharp enough to touch up with a strop for a long while.
Like others have said, use a cheapo razor for that job. The salt blocks will kill any steel edge so destroy the razors not your knife. Much cheaper and easier to replace than a native.
 
I hate to nitpick, but if you do want to open salt boxes with an expensive knife, you might just consider any one of the many fine "hard use" brands out there which can take a hell of a beating without issue. *shrug* Its just you kinda have to get one of these knives to believe it, at least if you've spent years tolerating S30v which seems to take damage to the edge if you do just about anything with it.

[video=youtube;fUK1cWpXSO4]http://www.youtube.com/watch?v=fUK1cWpXSO4[/video]

Yeah its kinda amazing like that. ;) Different strokes for different folks I guess.

I have heard good things about Spyderco's 3V actually, but not had the pleasure of trying that one myself. ;)
 
CPM S30V has very large carbides that need to be well supported.

The carbides themselves are super tough.


The key is giving the carbides enough support while polishing the edge to the required refinement.


I suspect you're seeing carbide tear out on that thin edge.





Big Mike
 
So I decided to go ahead and try out Spyderco vg10 (Endura) today. Since this was decidedly more a test than anything else I used it on three boxes with no attempt to save the edge, unlike with yesterday's experience.

Edge angle is the same although not quite as polished. Obviously the blade on my Endura 4 is much longer than on the Native so I tried to keep the cutting portion approximately the same. Interestingly (at least to me) there was no damage, edge deformation or any obvious sign of use.

These "tests" are far from scientific, nor are they anything approaching conclusive, obviously, so... I need to figure out what I can do next to get a more thorough result.
 
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