A Queen with a problem

[treefarmer]

Several weeks ago I posted a Queen Big Chief that was malfunctioning. It opened and closed without the normal snap and the half stops, it functioned and felt like an Opinel friction folder's action.
I took it apart after David (edge223) asked if the spring was broken or worn. https://www.allaboutpocketknives.com/kn ... 80#p938098
It looked as if the blade was worn and after taking the blade out of the frame we can see how badly it is rounded off, similar to a knife without half stop but having no effect on the spring.
Here is what the blade looks like:

#45 disassembled

blade should look like this on both sides

Notice the unusual wear on the mark side

Would have been decent Big Chief had it not malfunctioned, must have been many moons ago to wear the blade tang down like that

The spring also had considerable wear where it had been rubbed by the blade

Any ideas what went wrong?
Treefarmer

[edge213]

Poor heat treat, never oiled??

[treefarmer]

David, let me add one more picture, the frame/handle has a stress crack, metal fatigue maybe where the top end of the spring seated in the frame.

Maybe this part of the aluminum was thin and gave way resulting in the unusual wear.
Treefarmer

[herbva]

Two things that I know of cause that kind of blade and spring wear. First, the knife probably has been opened and closed a zillion times. Some people will sit there compulsively or habitually opening and closing a knife all the time. Lack of oil will just speed up the wear this kind of opening and closing abuse causes. Second, the blade wasn't set tight enough in the frame to begin with and had some room to "wander" off the spring a tiny bit. So, the thin ribbon or strip of tang not worn down that you see in your picture actually was no longer in contact with the spring. The knife either was not assembled correctly or something happened (like a pivot pin breaking or coming loose).

[OLDE CUTLER]

Two things that I know of cause that kind of blade and spring wear. First, the knife probably has been opened and closed a zillion times. Some people will sit there compulsively or habitually opening and closing a knife all the time. Lack of oil will just speed up the wear this kind of opening and closing abuse causes. Second, the blade wasn't set tight enough in the frame to begin with and had some room to "wander" off the spring a tiny bit. So, the thin ribbon or strip of tang not worn down that you see in your picture actually was no longer in contact with the spring. The knife either was not assembled correctly or something happened (like a pivot pin breaking or coming loose).

[ea42]

Biggest cause of that kind of wear is a complete lack of oil. Couple that with grit in the tang area and you'll have that result in no time at all. I'm also wondering if perhaps the back of that shell was too tight against the spring, possibly preventing it from extending all the way at which point the blade was forced open and closed by the user. That'd certainly cause premature wear as well and might explain that crack.

Eric