Will a Quality Axis-lock Open When Dropped?

J

jayjaygee

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I recently asked a similar question about a Spyderco Shaman, and it made me wonder if a Benchmade - especially a heavier one, since that seems to be a contributing factor - will open when dropped. I'm coming from the world of Buck lock-back folders so it was a real surprise to me when the Shaman opened by itself.
 
Did it open by itself or open when dropped? That's not a question of quality, and it is expected that a liner lock or framelock will open if dropped. They stay closed with a detent ball, and a quick shock can easily push the blade past that detent. Axis locks don't have a lot of resistance against the blade, either, but they have a little bit of backwards tension that can pull the blade back in if the shock isn't too hard. So it's a little less likely to happen than with a liner, but still can happen.
 
All a knife has to do is defeat the detent/omega spring in order to come open. I see no reason why it wouldn't have a chance of doing so if it hits the ground. My Adamas will snap open if I wrist flick it. It's a big heavy blade that pushes back on the cross bar easily enough to engage the blade open when you give it a little English or the wrist.

There isn't nearly as much tension on the blade as there is with a lock on the back of the knife.
 
Tsujigiri said:
Did it open by itself or open when dropped? That's not a question of quality, and it is expected that a liner lock or framelock will open if dropped. They stay closed with a detent ball, and a quick shock can easily push the blade past that detent. Axis locks don't have a lot of resistance against the blade, either, but they have a little bit of backwards tension that can pull the blade back in if the shock isn't too hard. So it's a little less likely to happen than with a liner, but still can happen.
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Well it was a hypothetical question but since you asked for specifics I borrowed a neighbor's Kershaw axis-lock knife and dropped it on a carpeted floor and it opened fully (engaging the lock) and now he's mad at me. :) Opened twice, did not open twice. Seems to have to do with where it lands.

Steely_Gunz said:
All a knife has to do is defeat the detent/omega spring in order to come open. I see no reason why it wouldn't have a chance of doing so if it hits the ground.
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Makes sense. I don't think I like it though. I might have to stick to my Bucks. Particularly someday when I'm old enough to drop things more easily, and to be wearing slippers more often.
 
Ouch! Yes an axis lock knife can open from a fall but it depends what part of the knife contacts the floor, does the angle of force cause the blade to move away from the handle or not.
 
jayjaygee said:
I recently asked a similar question about a Spyderco Shaman, and it made me wonder if a Benchmade - especially a heavier one, since that seems to be a contributing factor - will open when dropped. I'm coming from the world of Buck lock-back folders so it was a real surprise to me when the Shaman opened by itself.
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Yep. Omega springs don't apply much bias towards closure.

The first answer you got in your Shaman thread also applies to crossbar locks:
kreole said:
Yeah it can easily. A little shock will pop a leaf spring out of place, and there's no bias to closure once the detent is out of place. Same can happen with liner and frame locks
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And I'd add that it applies more broadly to lots of locking mechanisms for folding knives. I'm sure there are other less-common mechanisms that also stay closed better when dropped. I'd be surprised if a lockback, slipjoint, Tri-Ad lock, or anything along those lines popped open when dropped.

But if it folds and doesn't have a backspring or something analogous to one...get your feet clear if you drop it. 😆
 
Well, I'm not proud to say this, but this thread got me to test my EDC Adira. I dropped it 3 times from waist high onto a carpeted hardwood floor without it opening. On the 4th drop it landed on its side with the lock bar hitting the floor. It opened completely.

Moral of the story: Don't drop your knives:rolleyes:(or any tools, guns, babies, etc.)
 
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Steely_Gunz said:
All a knife has to do is defeat the detent/omega spring in order to come open. I see no reason why it wouldn't have a chance of doing so if it hits the ground. My Adamas will snap open if I wrist flick it. It's a big heavy blade that pushes back on the cross bar easily enough to engage the blade open when you give it a little English or the wrist.

There isn't nearly as much tension on the blade as there is with a lock on the back of the knife.
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Yep, I can and enjoy wrist flipping my SHFs
 
I've had it happen. The spring/tang combo BM uses isn't that strong of a force really
 
Thats what I like about the Tactile Maverick.Three escalating spring tension adjustments. From flick it open to no chance.
 
I don’t really care all that much if a knife opens when I drop it. I rarely drop my knives and on the rare occasions when I do, it’s already opened.

I’m a fan of Crossbar locks regardless of who makes them but I’m also a fan of Buck knives. Can’t wait to try out Buck’s new Range series of Crossbar lock knives.
 
jayjaygee said:
I recently asked a similar question about a Spyderco Shaman, and it made me wonder if a Benchmade - especially a heavier one, since that seems to be a contributing factor - will open when dropped. I'm coming from the world of Buck lock-back folders so it was a real surprise to me when the Shaman opened by itself.
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I'd have to run the experiment several more times I guess to know more about it, but I just dropped my Benchmade Presidio II on a hardwood floor from waist high three times on each of it's six "sides" and it never opened. The Lightweight Manix2 I have came open the first drop. The Presidio II takes more force to open the blade without moving the lock bar than the Manix2 does So maybe quality isn't really the right word. Just the axi and ball bearing locks being different designs in how they engage the tang. But I'm glad you asked this question and that I tested my own knives, I now have more confidence in the Presido II as an EDC than I do the Manix 2....
 
I am blown away that axis locks are opening from the shock of hitting the floor.
Many / most all of my Benchmades STRONGLY "suck" the blade into the handle even when the blade is a good 10mm or more gap between handle and edge near the tip . Seems like I recall my 710 can be open 20mm or more and when I release the axis the blade flies up into the handle .

I beg to differ about the term "detent" . Some / all liner locks and frame locks have a ball in a hole and to me that is a DETENT but with an axis lock or a back lock , heck even a slip joint, there is a good amount of CAM lobe type action that works on the blade over a MUCH wider range of the blade being starting to open but then gets forced back into the locked position .

I think the only knives I have dropped have been compression lock Spydercos and then because my fingers were taped and slick because of winter split fingers.
Meaning I haven't dropped my axis lock knives so I have no empirical experience there only theory .
 
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