710-Axis lock instability issues
I have a current 710-Axis (M4) and it has an issue with lock instability.
Specifically if the pivot gets loose it is very trivial for the lock to release under loads on the spine.
It happened when doing heavy cutting and after that I verified it was spine loads causing it by simple light impacts on the spine which would cause the lock to release.
Is this the expected behavior of the lock?
Specifically if the pivot gets loose it is very trivial for the lock to release under loads on the spine.
It happened when doing heavy cutting and after that I verified it was spine loads causing it by simple light impacts on the spine which would cause the lock to release.
Is this the expected behavior of the lock?
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No, it should'nt happen and it's the first time I've ever heard of it.
If I understand correct the lock bar does not ride up far enough on the back of the blade tang to lock it in place securely.
Send it in to BM and they should fix it, you'll get back a perfect, issue free knife.
Welcome.0 -
I agree with archer's reply, but just thought I'd add one more thing: Your premise was that "if the pivot gets loose". Well, that should never happen either. If you'll use some removable loctite on the screw or wrap it with teflon tape, the pivot won't get loose.
Basically, if the pivot is allowed to get loose and wobbly, then all bets are off as to how the lock will perform. It's like any other mechanism...if you loosen all the screws, it's not going to work correctly.0 -
Sending it back isn't an option as I don't live in the same Country and there are both cost and liability issues. If for example it was returned to me and the pivot was loose and the knife was able to be gravity opened it could be seized. If the proper paperwork was not filed I could be charged full import brokerage and duty costs.
I am just curious if this is the expected behavior of the lock if the pivot loosens.0 -
quote:
Basically, if the pivot is allowed to get loose and wobbly, then all bets are off as to how the lock will perform.
That was the question, so the expected behavior in that case then is that the instability of the lock is actually inherent to the design? That is to say, the knife isn't defective, that is the normal behavior if the pivot loosens?0 -
I would say yes, Cliff. The knife isn't defective. Apply the blue loctite or teflon tape to the pivot threads, tighten the pivot with a T-10 sized Torx driver to a point where it functions the way you want and then if you used Loctite, let it dry overnight and do your final adjustments the next day. 0 -
I'm having a hard time even picturing your scenario. For experiment sake, I loosened the pivot screw on a borrowed 710 until it was almost out and couldn't get the lock to come loose. Are you sure there is not something else going on, like a broken omega spring? 0 -
Loctite....it works.
Trust me
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Loosening the pivot screw has nothing to do with the axis lock but then of course how loose does it get, there is not enough tolerance in the Axis/pivot to cause it to fail even if the blade wobbles a bit, I just don't see it happening.
Read my analysis above and try and somehow mark how far the lock bar travel is, if it does travel up enough then slight vibration could cause the lock bar to move down enough for it to disengage.0 -
quote:Originally posted by AxisFan:
I'm having a hard time even picturing your scenario. For experiment sake, I loosened the pivot screw on a borrowed 710 until it was almost out and couldn't get the lock to come loose. Are you sure there is not something else going on, like a broken omega spring?
Even with an omega spring broken (and I've run around with a few), the lock won't slip or fail.
That said, I've had loose pivots before (with brand new out of box BM's), and I can't say I've had em fail on me.
Irriguardless, I'd still loctite that sucker.0 -
quote:Originally posted by sabu71:
Loctite....it works.
The question isn't how to stop the pivot from backing out, that was not even asked - however thread lockers are not a practical solution (in this case) for a number of reasons.quote:Originally posted by archer:
Read my analysis above and try and somehow mark how far the lock bar travel is, if it does travel up enough then slight vibration could cause the lock bar to move down enough for it to disengage.
The lock bar engages fully even with the pivot very loose. What happens is that vertical loads on the blade can cause lateral loads on the lock bar due to the slop when the pivot is loose.0 -
quote:Originally posted by Cliff Stamp:quote:Originally posted by sabu71:
Loctite....it works.
however thread lockers are not a practical solution (in this case) for a number of reasons.
Why wouldn't you want the pivot not to back out ???. Maybe it's just me, but if the pivot screw is causing you problems, that would be the first thing I'd do
Going further, from what you originally posted, you said the lock issues started when the pivot was loose, correct ????0 -
To answer your question originally. No it's not the expected behavior of the lock in that condition.
If the loctite doesn't help you, I'd say you have to send it in.0 -
quote:Originally posted by sabu71:
Even with an omega spring broken (and I've run around with a few), the lock won't slip or fail.
With 2 of em broke it will - been there, done that. Still not seeing his scenario though - any chance you can post a picture or 2 depicting the problem Cliff?0 -
quote:Originally posted by sabu71:
Why wouldn't you want the pivot not to back out ?
I would obviously, but thread lockers are not a practical solution to that in this case. The reason being is that it is not practical for me to have a knife which can not be maintained without used of thread lockers as I don't carry them with me at all times. As noted previously, it also isn't practical to return it for service for reasons stated.
What I wanted to know is it the expected behavior of :
-the pivot to back out so quickly
-the lock to get instable if the pivot backs out0 -
First item...it is expected (IMVHO)....loctite it, or use teflon tape....I do that with all my folders (BM or otherwise). If the pivot starts to back out, I bust out the blue loctite.
Second item....no it's not.0 -
quote:Originally posted by AxisFan:quote:Originally posted by sabu71:
Even with an omega spring broken (and I've run around with a few), the lock won't slip or fail.
With 2 of em broke it will - been there, done that. Still not seeing his scenario though - any chance you can post a picture or 2 depicting the problem Cliff?
Never had two of em break on me (at least not simutaniously anyhow). Still can't see the lock failing. Maybe hard to disengage, but that's about it.0 -
quote:Originally posted by Cliff Stamp:quote:Originally posted by sabu71:
Why wouldn't you want the pivot not to back out ?
I would obviously, but thread lockers are not a practical solution to that in this case. The reason being is that it is not practical for me to have a knife which can not be maintained without used of thread lockers as I don't carry them with me at all times. As noted previously, it also isn't practical to return it for service for reasons stated.
What I wanted to know is it the expected behavior of :
-the pivot to back out so quickly
-the lock to get instable if the pivot backs out
Cliff, I agree that it is not ideal to have to apply loctite or any other substance to keep your knife for an extended period of time, but like anything high-end knives are those of trade-offs. You simply can't have the option to adjust the pivot so easily without the probability that it will loosen without using a thread locker. It'd be nice to have both, believe me I'm with you. But as they say we can't have our cake and eat it too.
That being said, I use plumbers tape instead of loctite. I find it to be less messy and easier to apply/remove/replace. Not to mention it doesn't have a "setting/drying" time so adjustments can be made immediately after applying. You said that its unrealistic to be expected to carry loctite/tape with you everywhere which is true - but personally I have never been in a situation where I not only HAVE to open up my knife immediately before I get home but then also HAVE to lock the pivot before I get home too. YMMV but I think if you use tape, the worst situation you'll run into is opening your knife one day for whatever reason and having to wait until you get home later that day to lock the pivot again. IMHO not really something that bothers me much.0 -
Greetings Cliff!
Long time since we swapped bytes, ay?
Good to see you are still interested in knives. My love for them has not diminished at all in the last ten years.quote:Originally posted by Cliff Stamp:
...Is this the expected behavior of the lock?
No, not hardly, not my expectation. This takes me back a long ways, to when the Axis lock first came out and made the liner lock utterly obsolete...well except for fancy hand made gents folders. Back to the days of the infamous SPINE WHACK TEST.
Oh what wailing and gnashing of teeth that inspired.
I've put the Axis lock through the ringer, and never had one release on me under any circumstances. But I've never tried it with a loose pivot until today. Had never thought of it. It is was an interesting proposition.quote:Originally posted by Cliff Stamp:
...if the pivot gets loose it is very trivial for the lock to release under loads on the spine.
So I took my 551 Griptilian out to the shop and loosened the pivot a turn, some blade play, and gave the spine of the blade some moderate whacks with no releases. So no failure with a "loose" pivot...how about with a missing pivot?
I backed the pivot screw out three or four turns and pushed on it so that the pivot pin was backed out of the handle a bit, should have been enough so that the front of the pivot pin was no longer engaging the liner, and whacked away...no failure.quote:Originally posted by Cliff Stamp:
...It happened when doing heavy cutting...
...so I cut into some heavy gauge cardboard and started twisting and yanking against the spine, again with the pivot pin sticking out of the back...no release.
Even with the tension screw completely backed out, where the pivot is just held together by the liners and scales, there does not seem to be any inherent tendancy for the Axis lock to release under pressure. I'm sure if one de-constructed the knife completely at some point nothing would work, but under anything like normal use, I don't see where enough side play could result to defeat the lock's design. I think you've got some problem with your knife, or...expecting it to perform in an essentially partially assembled condition.
The first question that comes to mind is, is there any axial blade play with the pivot adjusted normally?
If yes, it may indicate that the lock bar is not completely engaging on the ramp...possibly due to some liner damage?
It is common for the pivot tension screw to loosen without some thread locking substance such as nail polish on the threads. But adding some nail polish, teflon tape, or blue Loctite will fix that problem for an extended period, months, certainly longer than a typical sojourn far from the workbench. And even if it does loosen completely, the lock should still work...as long as the pivot pin itself isn't backed out of the handle.
Great to hear from you Cliff! I hope we see more of you here!
Is the 710 your first experience with the Axis lock? You must have had some Axis lock folders by now...0 -
quote:Originally posted by Echo117:
It'd be nice to have both, believe me I'm with you. But as they say we can't have our cake and eat it too.
Care needs to be taken here as I have lots of knives that don't use thread lockers and the screws don't back out nearly this quickly.
I have a Modulator that I don't use thread locker on and it is perfectly fine. Now before anyone jumps to apples-to-kiwis due to the price, that is just the knife I am carrying now, I don't thread lock the Cold Steel AK-47 either and it can easily do 10X the work which causes the 710-Axis to see screw backout and it isn't at all affected.
I would vastly prefer to carry the 710 over the AK-47 for a number of reasons (ergonomics mainly) but if I can't resolve the pivot issue that is more critical obvious.quote:Originally posted by sabu71:
If the pivot starts to back out, I bust out the blue loctite.
While I appreciate the suggestion, I have noted several times that thread lockers are not practical options in this case.quote:Originally posted by Po:
Good to see you are still interested in knives. My love for them has not diminished at all in the last ten years.
The Dinosaurs are still around, though habitats change from time to time.quote:Back to the days of the infamous SPINE WHACK TEST.
Yes, Steve spoke of it very strongly with his own version of that which included taping the knives to poles and sparring dummies. Though his work is more precisely described as spine beating.quote:
I backed the pivot screw out three or four turns and pushed on it so that the pivot pin was backed out of the handle a bit, should have been enough so that the front of the pivot pin was no longer engaging the liner, and whacked away...no failure.
That is what I would have expected because there isn't an obvious way for the forces to be lateral, thus I would not have guessed it would become unstable and thus I was a bit surprised when it happened.quote:
The first question that comes to mind is, is there any axial blade play with the pivot adjusted normally?
No.quote:
If yes, it may indicate that the lock bar is not completely engaging on the ramp...possibly due to some liner damage?
The bar engages fully.quote:
Is the 710 your first experience with the Axis lock? You must have had some Axis lock folders by now...
Yes, I have one of the original Ritter RSK's in the first generation S30V.
That was one of my causes for puzzlement as that knife is quite old, heavily used (reground many times), and still very stable and doesn't exhibit these issues.0 -
Cliff, no offense, and not trying to cross sword here, but it sounds like you might have to send it in (and I understand the issues with overseas shipping/laws). But unless you've got someone local that can look at/fix it, then it might be your only hope (don't understand "not practical" bit with using loctite...are you allergic to it or something ???).....but I'm thinking that's not normal (with the caveat that I have had the same model for over 10 years, The 710hssr, and outside of one broken omega spring which I had corrected, I've never had an issue with the knife. And I'm not one to baby my knives).
But that all said, I hope you find peace, and get your issue solved (one way or the other)0 -
Oh, and irony of ironies, I have a 710HS on me today (well with my Contego too )0 -
quote:Originally posted by Cliff Stamp:
...I would vastly prefer to carry the 710 over the AK-47 for a number of reasons (ergonomics mainly) but if I can't resolve the pivot issue that is more critical obvious...
It is a fair knock, and you are not the first to make it. Along with great steel, awesome designs, and the Axis Lock, you get cowardly pivot tension screws (always backing out). But as Jon and others have mentioned, the fix is elementary. A dab of blue Loctite and I forget about my pivots for months...years. Nail polish, plumbers teflon tape, prolly Elmer's, rubber cement, pine tar, or almost anything tacky would work.0 -
quote:Originally posted by sabu71:
Cliff, no offense, and not trying to cross sword here, but it sounds like you might have to send it in (and I understand the issues with overseas shipping/laws).
It simply isn't practical, I normally buy everything through resellers I know to avoid issues. I normally only return items if the maker/manufacturer wants to specifically inspect them because for me it is always more cost effective to simply buy replacements - hence the question is it to be expected.
When I do return items I have a fairly simply but detailed list of shipping instructions which gets followed about 50% of the time and the other 50% I get hit with items bounced, full import and brokerage charges and even seized items. It is possible to fight all of these but it would take more time that the item is worth.
Now as to why I rarely use thread lockers :
a) I don't support using them in general on knives because I have knives that don't need it, that I never use it and thus it is simply a matter of quality. At a certain price point I would consider it a defect if a knife was not functional without a thread locker, especially if it happens in literally a few minutes work.
b) I often loan knives to friends, family and in general want my knives to be very versatile. Having to resort to glueing fasteners in place isn't thus ideal, because they are not going to.
c) I never carry thread lockers on me at all times (though you can improvise semi-decent ones out of any very thin material)and having a knife which requires it is thus less than ideal because to maintain it requires special materials.
I do realize different people have different tolerances, but for me the main issue here is how fast the knife becomes loose and as a followup that it becomes unstable after that. Now if it took a week of carry, no issue. If I had to tighten it at the end of a day, a little annoying but still workable, but not every few minutes.
Nice knife though and nice to see the steel, I was one of the first to actively campaign for more HSS when they first started using M2. Though then, as now, I would prefer a slimmer edge profile given the nature of the steel. In its current configuration it would be simpler to use D series steels as they also have very high wear and would be stable in the edge thickness/angle that this one has (assuming it is representative).0 -
Well, to me, the choice seems to be between the inherant inadequacies of the liner lock which cannot be fixed, and a small flaw which is elementary to fix. It truly is a set it and forget issue. Nobody is carrying Loctite around with them.
Second thought: we are talking folding knives here. If you want to carry a knife far and away from a tool kit, where extended extreme use could make a small flaw into critical failure, a folder of any design may be inadequate, and a fixed blade the right solution.
The other aspect of this is that, I have not experienced lock-up problems related to a loose pivot, even to the extent of the pivot screw being completely backed out. I think that issue is only related to that knife.0 -
I agree. Of the many Benchmade folders I've had, I have only added loctite to a few and once that is done, I haven't had to do it again, ever. Po, your comments regarding liner-locks, fixed blades and lock-up problems also seem spot-on.quote:Originally posted by Po:
Well, to me, the choice seems to be between the inherant inadequacies of the liner lock which cannot be fixed, and a small flaw which is elementary to fix. It truly is a set it and forget issue. Nobody is carrying Loctite around with them.
Second thought: we are talking folding knives here. If you want to carry a knife far and away from a tool kit, where extended extreme use could make a small flaw into critical failure, a folder of any design may be inadequate, and a fixed blade the right solution.
The other aspect of this is that, I have not experienced lock-up problems related to a loose pivot, even to the extent of the pivot screw being completely backed out. I think that issue is only related to that knife.
I have a knife like the one being discussed above. I just completely removed the pivot screw and it had no effect on the lock-up. BTW, the pivot screw already had thread locker on it from the factory.0 -
I think I've had one Benchmade that I used Teflon tape on, I see it as the screw and pivot both being on opposite ends of tolerance, and the possibility that oil somehow got in and leaves it free to unscrew, possibly both.
I use my knives, I've broken tips and all the rest, never once has a blade unlocked on me.
An axis knife that won't lock or stay locked is useless, is a factory defect and instead of being so inflexible with something as trivial as a drop of thread locked or plumbers tape, it's arbitrary, I've had cheaper knives swing open and closed like hydraulics with only gravity, had them free swing with gravity and all the while have no blade play, I should expect every knife at and above that price point to operate as smoothly?
Just applying your 'standard' and being inflexible makes little sense when it comes to production knives.
I think the answer is clear, send it to the factory for the faulty lock and have them look at the pivot as well, there is no other advice that will solve your problem.
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quote:Originally posted by Po:
If you want to carry a knife far and away from a tool kit, where extended extreme use could make a small flaw into critical failure, a folder of any design may be inadequate, and a fixed blade the right solution.
In general, if I could carry a fixed blade I would. The only reason in general to carry a folding knife is because it can be carried in some cases where a fixed blade can not. In areas of use, performance, maintenance and especially cost - fixed blades are inherently vastly superior.quote:Originally posted by Skimo:
I think the answer is clear, send it to the factory for the faulty lock and have them look at the pivot as well, there is no other advice that will solve your problem.
I have noted why returning it isn't a solution. There are any number of solutions which are perfectly functional, hence I never asked for them as they are known. Again, all I wanted to know is if what I saw was the expected performance.0 -
quote:Originally posted by Cliff Stamp:
Again, all I wanted to know is if what I saw was the expected performance.
No. That is not normal.0 -
It just seems odd that any knife nut who's been around the block would know that lock failures are not expected from any quality manufacturer. That absent abuse the lock should never disengage without it being wanted. 0 -
quote:Originally posted by Skimo:
It just seems odd that any knife nut who's been around the block would know that lock failures are not expected from any quality manufacturer.
There are a number of issues which make this not at all trivial.
A) The acceptance of what is reasonable use is not uniform.
There are makers/manufacturer who even limit inertial openings to be abusive, though this has lessened since the popularity of flippers. A maker or manufacturer could easily say that what is being discussed here isn't a lock failure, it is simply exceeding the scope of work of the knife.
In more detail, in this video : http://www.youtube.com/watch?v=oUL67VX6kDs you can see the level/type of impacts which release it.
Again, the release first happened in cutting, this was done just to verify it was spine load instable, the impacts are in the middle of the video (3:35). Further, the critical issue is that the lock doesn't break, it just releases which is an instability issue not a strength issues.
There is always dispute over spine loads and thus the collapsing could or could not be considered a failure from the point of view of the maker or manufacturer. Hence it is also helpful to do something, or provide some level of information on what kind/type/extent of load is being applied.
B) The lock only becomes unstable once the pivot is loose, thus it is a design tolerance issue if it is in fact an issue and not simply a one-shot defect.
C) While I have used this lock, and have corresponded with others on it extensively, it is mainly based on information from the time it was first put out, manufacturing tolerances, goals and design may have changed since then.
and finally :
D) What I know, or deem to be correct and what the maker/manufacturer deems to be correct are not always the same, hence I normally ask for confirmation and if it is so different would annotate any references with that information. Thus even in the event it is clear from my perspective I would ask out of completeness.
E) I am always curious about customer service and forum response to these types of issues because this response can be more telling than the issue itself at times, so again I ask out of completeness.0
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