The death of a BK4 (broken knife, opinions wanted)

Joined
Mar 6, 2014
Messages
2,137
Any idea what would cause a break like this?
Ive had this blade for at least the past five years, and its been one of my best. While i was splitting some little fatwood starters, i felt the blade lurch forward as the front half fell off
it was inside, nice and warm
never abused, left outside, nothing
well used and well loved, but also closely cared for
also, it seems there was a small amount of rust inside of the crack, towards the edge?
 
Looks like it broke at the area with the least amount of metal.

You could contact Ka-Bar. They are generally pretty good about customer service.
 
Who's knife was this? Camillus, Ka-bar or Blackjack?

It looks like the failure started at the edge, where some rust had developed.

Can you post better (clearer -larger) images?

n2s
 
Who's knife was this? Camillus, Ka-bar or Blackjack?

It looks like the failure started at the edge, where some rust had developed.

Can you post better (clearer -larger) images?

n2s
I haven't used the forum in ages, how aught I go about posting a clearer picture?

It's a ka-bar one, a couple of years old
 
my suggestion is to email KaBar with the pictures and ask if they can email you a shipping label so it can be sent in for testing and possible warranty replacement.
This. :thumbsup:
 
Strange how there's rust inside the break. Seems to have had a crack in it for a bit.
 
I enlarged, and enhanced this photo a bit. You can really see the crud/rust in it:

 
You didn't hit the blade with the baton where the break is, did you?
 
my suggestion is to email KaBar with the pictures and ask if they can email you a shipping label so it can be sent in for testing and possible warranty replacement.
This.

Wow, Iโ€™ve never seen a break quite like that. Iโ€™d bet there was inclusion somewhere in the steel where it broke.
Thatโ€™s wild. Never seen a break like that before.
 
This.

Wow, Iโ€™ve never seen a break quite like that. Iโ€™d bet there was inclusion somewhere in the steel where it broke.
Thatโ€™s wild. Never seen a break like that before.
My guess is there was a microfracture, which is where the break started, then it followed the roll stamp.
No idea if the initial fracture was an inclusion, flaw in the metal from day 1, or happened after delivery.
I have seen a similar break at a gathering - where the guy was splitting firewood and the blade snapped die to a knot in the wood creating weird internal stresses right at the "T" in the roll stamp.
That's part of why kabar made the switch to laser etching - removes the chance of a stress riser. (And its a little cheaper than replacing the roll die)
 
My guess is there was a microfracture, which is where the break started, then it followed the roll stamp.
No idea if the initial fracture was an inclusion, flaw in the metal from day 1, or happened after delivery.
I have seen a similar break at a gathering - where the guy was splitting firewood and the blade snapped die to a knot in the wood creating weird internal stresses right at the "T" in the roll stamp.
That's part of why kabar made the switch to laser etching - removes the chance of a stress riser. (And its a little cheaper than replacing the roll die)
Is this blade a stamped one?
I was thinking this too
 
Back
Top