Who's fault is this, Magnacut or Kershaw?

Z

ZacharyLIU

Joined
Feb 29, 2016
Messages
1
Bought this blur a week ago, carried three times, today I see this. My another blur with 14c28n steel which I carried over a year is fine.

bare links removed. do not send members offsite. please post images by editing your post, selecting the image icon and linking your images.
 
Last edited by a moderator:
That just sometimes happens with press fit thumbstuds (if that’s how those are mounted), this has been shown here before even with CRK knives. It induces stress on a small area and while it’s not everyday common, this is an unfortunate result of that method.
 
It's the fault of the QC person who let that product be shipped out. That fracture happened in fabrication, not normal EDC use.

I think their CS will take care of you.

Remember, people are machines too and anyone can break down or fail. Talk to their CS folks.
 
Delgadonine said:
That fracture happened in fabrication, not normal EDC use.
Click to expand...

The tiny stress fracture may have been there from the get go but sometimes it can take quite a while before it works its way through, there’s been several CRK instances where the crack suddenly appears after several years of ownership, they’ll replace the blade if this happens under warranty because they wouldn’t have been able to catch this in final inspections or during boxing/shipping.
 
Jsega51 said:
The tiny stress fracture may have been there from the get go but sometimes it can take quite a while before it works its way through, there’s been several CRK instances where the crack suddenly appears after several years of ownership, they’ll replace the blade if this happens under warranty because they wouldn’t have been able to catch this in final inspections or during boxing/shipping.
Click to expand...
Diplomacy.

It's entirely possible that we are both correct.

Particularly about Customer Service, Warranty and so on.

Kershaw likely will address the issue.

I believe.
 
Always a good practice to contact manufacturer as the first step to correcting an issue the retailer can't, or isn't responsible for. Big box retailers don't open every box to make sure the product isn't broken, so chances are, sadly, plenty of knives with issues are still on shelves waiting to be bought and shipped out. So, contact manufacturer
 
It’s not the blade steel’s fault. The crack started where the thumb stud meets the blade. Perhaps too much force was exerted in installing the thumb studs. Regardless, Kershaw’s warranty will make it right.
 
DocJD said:
Sure be nice to see some pics ! :( Blade broken through thumb stud hole ?

I'm trying to understand the problem from context ...but .
Click to expand...
2v2ertRn9xAWtWs.png

2v2ertRFMxAWtWs.png
 
I have had this on a couple knives, a Strider and a . Hinderer., though not as blatant. I never noticed it, but the person I sold them to sure did :)
As long as the knife wssn't modified, it should be covered under warranty.
 
Twindog said:
2v2ertRn9xAWtWs.png

2v2ertRFMxAWtWs.png
Click to expand...
Thanks !

So , some thumb studs are just sort of riveted in... really hard ? :eek:

Only ones I've removed , have been Cold Steel threaded type . But just making a hole could create problems , I'd guess .
 
DocJD said:
Thanks !

So , some thumb studs are just sort of riveted in... really hard ? :eek:

Only ones I've removed , have been Cold Steel threaded type . But just making a hole could create problems , I'd guess .
Click to expand...

I know Chris Reeve knives uses a press to install the thumbstuds. I'm sure they aren't the only ones.
 
Any sharp angles or holes will create a stress riser. Usually, that weakness doesn't cause a problem, but it does weaken the blade and can cause problems every so often, as the OP mentioned. I always disliked the way Spyderco ran a sharp plunge line into and through its Spyderhole, creating a double stress riser. Obviously, it's seldom a problem in real life, but it has aways bothered me from a design standpoint.

Some years ago, I had this benchmade in M4 steel rehardened from 59 Rc to 64 Rc. When I reinstalled the blade, it was off center, so I was using hand pressure to try to center it. Problems ensued. That hole is a weak point, and the process of drilling it adds additional stress lines of weakness.

2v2ae2RokxAWtWs.jpg
 
💯💯
Good post.

Sam⚔️⚔️

Twindog said:
Any sharp angles or holes will create a stress riser. Usually, that weakness doesn't cause a problem, but it does weaken the blade and can cause problems every so often, as the OP mentioned. I always disliked the way Spyderco ran a sharp plunge line into and through its Spyderhole, creating a double stress riser. Obviously, it's seldom a problem in real life, but it has aways bothered me from a design standpoint.

Some years ago, I had this benchmade in M4 steel rehardened from 59 Rc to 64 Rc. When I reinstalled the blade, it was off center, so I was using hand pressure to try to center it. Problems ensued. That hole is a weak point, and the process of drilling it adds additional stress lines of weakness.

2v2ae2RokxAWtWs.jpg
Click to expand...
 
One thing to remember is that the original blade steel on the Blur was 13C26. Later it was 14C28. Those are both significantly tougher alloys than magnacut, let alone S30V or M390. My thought is that Kershaw's manufacturing engineers should have taken that into consideration when changing alloys. Should have looked at the manufacturing design and perhaps modified the hole dimensions. Just a thought. Hindsight being 20:20 and all.
 
You must log in or register to reply here.
Back
Top