Siren - strange lock movement

[jpm2]

Mine does it too, but not gonna worry about it unless it interferes with use. So far it hasn't.
When I get curious enough, I'll take it apart and see why.

[sal]

It does not appear to be a safety issue. We're working on it. My guess is an angle deviation by a degree or 2.

sal

[JRinFL]

It does not appear to be a safety issue. We're working on it. My guess is an angle deviation by a degree or 2.

sal

What about those with knives showing dramatic lock movement, like mine? Is it a warranty issue, or grin and bear it?

[VooDooChild]

Couldnt this also damage the spring?

[craytab]

I'd worry more about wear on the lock at the point the slipping occurs. It almost makes an audible "pop" when the lock completely disengages.

[jpm2]

I'd worry more about wear on the lock at the point the slipping occurs. It almost makes an audible "pop" when the lock completely disengages.

That would my concern too.
Out of curiosity, I just now pulled out a delica k390, native 5 m4, and a pacific salt (what was in immediate reach :) ). With them open, I held the lock bar down (up at the tang), and put pressure on the tip. With pressure on the tip, I released the lock bar and it stayed in place with all of them. When I relaxed presssure on the tip, the lock bars fell back in place.

Curious if anyone else can duplicate the above with their non siren back locks.

[DSH007]

Yep, mine too!

Best I can tell from messing around with it in various grips, it doesn’t seem like a huge safety issue for light tasks (especially with my thumb over the lockbar, which mitigates it from wanting to pop up), but it certainly doesn’t inspire confidence either..

[DSH007]

Mine does it. So coupled with my grip loosening the lock and making the blade feel rattly, and the very narrow margin for avoiding the blade when closing it, I'm going to sell my Siren. I don't think it's unsafe, there are just too many idiosyncrasies to the knife for me to think about while handling it.

Sal does not want them sent in. He said in the BF thread that they had enough in house to check.

I think this is a fair assessment. I haven’t carried mine much since summer, but thinking back on it, I do remember having to be much more “aware” of the knife when using it, for all of the reasons you list.. I don’t think I’ll sell my Siren because I love the ergos, light weight and corrosion resistance for summer carry. I’ll definitely think twice about making any really hard cuts now though..

[jpm2]

Yep, mine too!

Best I can tell from messing around with it in various grips, it doesn’t seem like a huge safety issue for light tasks (especially with my thumb over the lockbar, which mitigates it from wanting to pop up), but it certainly doesn’t inspire confidence either..

I think I could post similar pictures of all my back locks, although not by just pressuring the tip.
Until further notice, I have no reservation of using/beating on the siren as hard as I like.

[DSH007]

Yep, mine too!

Best I can tell from messing around with it in various grips, it doesn’t seem like a huge safety issue for light tasks (especially with my thumb over the lockbar, which mitigates it from wanting to pop up), but it certainly doesn’t inspire confidence either..

I think I could post similar pictures of all my back locks, although not by just pressuring the tip.
Until further notice, I have no reservation of using/beating on the siren as hard as I like.

Pictures don’t do the problem justice. It’s not behavior exhibited by a normal backlock.. certainly not one I’ve ever used.. I tried a quick video of my Siren vs a Stretch, Delica, Native (g10, lw, chief). None of these back locks have this issue.

I’d never tell you how to use (or not use) your knife.. but as far as I’m concerned, one of these seems a whole lot less safe than the others..

https://streamable.com/3166lm

^ I’ve never posted a video before, I have no idea if this link is going to work.. please let me know haha.

[VooDooChild]

I'd worry more about wear on the lock at the point the slipping occurs. It almost makes an audible "pop" when the lock completely disengages.

That would my concern too.
Out of curiosity, I just now pulled out a delica k390, native 5 m4, and a pacific salt (what was in immediate reach :) ). With them open, I held the lock bar down (up at the tang), and put pressure on the tip. With pressure on the tip, I released the lock bar and it stayed in place with all of them. When I relaxed presssure on the tip, the lock bars fell back in place.

Curious if anyone else can duplicate the above with their non siren back locks.

Thats just the design of a standard backlock. Since the lockbar acts the same as a stop pin in other designs, having the lock disengaged is the same as the "stop pin" being moved slightly back. So if you opened the blade through as much of the opening arc as possible with the lockbar disengaged, and theres enough pressure/friction between the blade tang and lockbar, it will keep the lockbar in an "up" position until that force (force at the tip) lets up.

Thats really not an issue. Because once the lockbar engages in its standard position, which it will do every single time unless you purposely force it not to, it shouldnt slide back up like the sirens are doing.

[jpm2]

I'd worry more about wear on the lock at the point the slipping occurs. It almost makes an audible "pop" when the lock completely disengages.

That would my concern too.
Out of curiosity, I just now pulled out a delica k390, native 5 m4, and a pacific salt (what was in immediate reach :) ). With them open, I held the lock bar down (up at the tang), and put pressure on the tip. With pressure on the tip, I released the lock bar and it stayed in place with all of them. When I relaxed presssure on the tip, the lock bars fell back in place.

Curious if anyone else can duplicate the above with their non siren back locks.

Thats just the design of a standard backlock. Since the lockbar acts the same as a stop pin in other designs, having the lock disengaged is the same as the "stop pin" being moved slightly back. So if you opened the blade through as much of the opening arc as possible with the lockbar disengaged, and theres enough pressure/friction between the blade tang and lockbar, it will keep the lockbar in an "up" position until that force (force at the tip) lets up.

Thats really not an issue. Because once the lockbar engages in its standard position, which it will do every single time unless you purposely force it not to, it shouldnt slide back up like the sirens are doing.

With that said, do you think it could be a safety issue, or just annoyance.
So far I haven't had it happen in use, but my specimen might not do it as easy as others.

[VooDooChild]

...
With that said, do you think it could be a safety issue, or just annoyance.
So far I haven't had it happen in use, but my specimen might not do it as easy as others.

Annoyance.

I want to make sure I am understanding what you said earlier. You opened the knife, put pressure on the tip, depressed the lockbar, and with the lockbar depressed it stayed "up" until the pressure was released. Is that correct?

If so then thats not a design flaw in the same way as whats happening with the sirens.

It could be a safety issue, but not because of design, but because youre disengaging the lock in the open position.

[jpm2]

...
With that said, do you think it could be a safety issue, or just annoyance.
So far I haven't had it happen in use, but my specimen might not do it as easy as others.

Annoyance.

I want to make sure I am understanding what you said earlier. You opened the knife, put pressure on the tip, depressed the lockbar, and with the lockbar depressed it stayed "up" until the pressure was released. Is that correct?

Yes, correct.

If so then thats not a design flaw in the same way as whats happening with the sirens.

But, it is the general design that is allowing what's happening with the siren?

It could be a safety issue, but not because of design, but because youre disengaging the lock in the open position.

I'm trying to see how it could be a safety issue, since the lock is only disengaging with pressure on the edge, and re-engages when pressure is relieved.

Other specimens might disengage more easily than mine, but takes excessive pressure for mine. Not that I'll never put that much pressure on mine in use, but would have to be extremely dull for it to happen.

[VooDooChild]

...
But, it is the general design that is allowing what's happening with the siren?

I'm trying to see how it could be a safety issue, since the lock is only disengaging with pressure on the edge, and re-engages when pressure is relieved.

Other specimens might disengage more easily than mine, but takes excessive pressure for mine. Not that I'll never put that much pressure on mine in use, but would have to be extremely dull for it to happen.

Im not sure about the general design, its probably like what was said earlier and the lock interface angles are ever so slightly off.

When I was talking about disengaging the lock I meant on other backlocks that arent doing what the siren is doing. Just sort of saying dont disengage the lock in the normal manner when using the knife. Because in that scenario your hand is going to keep the lock disengaged.

As far as the siren... I dont know. It seems like it still would not be a safety issue, as sal said earlier, and as you said since the lock will reengage after the pressure is released.

However if the lockbar somehow got stuck in that position then it could be bad.

[craytab]

Here's a couple posts I made over on bladeforums with pics:

My Siren also does this. I will say that it does take quite a bit of force to get this to happen. Still though, I'd expect this to not happen at all. This is a flaw that should be addressed. Checked all my other Spyderco lock backs (enduras, delicas, and various other salts) and none of them do this.

This is not good:


"Thinking back on my Siren use, there were a couple of times when I noticed the lock move while using. I attributed that to my hand position depressing the lock bar but I now realize this issue is what was happening. I used the siren in the yard to cut some tough vines against the wooden backyard fence. The vines were in a hard to get to place and I was in a position where I had to cut hard with pressure using just the tip of the blade. I could feel the lock move under my palm. Not a confidence inspiring feeling, especially now that I know what the cause was.

I'll have to take a look at it later today but if the lock stays disengaged after this happens, and one does not notice it, this could be a safety issue. I don't think we should have to worry about our knives having the lock disengage unless we mean to disengage them, especially when doing what seems to be fairly normal cutting."

"After messing with it a bit more, I agree that it is not a safety issue in the sense that when the cutting pressure is released on the blade, the lock re-engages. That said, it is still hard to fully trust a lock that does something like this. The lock seems solid in all other ways, I even gave it a couple of good spine whacks. At this point though, I wouldn't trust the Siren as a back up emergency SD blade because I wouldn't trust it for hard stabbing. I'm not willing to test a lock that will disengage like this in a stabbing test with my hand. This is really sad as it limits the do everything robust EDC roll that is the Siren's claim to fame. If a knife can't stab it might as well be a slip joint, which is fine, just not what it is advertised.

Even under different grips and putting the pressure at the base of the blade, the lock moves around in a really uncomfortable way. I guess I do most of they EDC tasks in a slicing motion rather than hard downward push cuts. In these pics I'm making sure not to be hitting the lock with my palm."

[craytab]

To summarize, I don't think this is a safety issue in that the lock seems to pop back into place when pressure is released on the blade. That said, I get lock and blade movement fairly easily. It is very disconcerting and I don't fully trust the lock, and thus the knife. The blade should not be moving when you use the knife.

I doubt this issue is intended and for me it does detract from the use of the knife. There are enough people reporting this that it does not seem like a few lemons slipped through QC.

Curious to hear what Spyderco says.

[vivi]

I was going through my drawer of folders touching up their edges, and when I got to my Siren I checked the lock again. Seems to be popping up all the way now, with less effort than before.

[JRinFL]

I was going through my drawer of folders touching up their edges, and when I got to my Siren I checked the lock again. Seems to be popping up all the way now, with less effort than before.

Yours looks just like mine does. It almost feels like it needs a lock to lock the lock!

[ChrisinHove]

I just watched Nick Shabazz’s tear down of the Siren on YT, looking specifically at the lock geometry.

The interelationship between the various interface angles, the lock bar and blade pivot locations looks flippin’ complicated....