Are ball bearing pivots just a marketing gimmick?

[Comeuppance]

Yes. They add an unnecessary complexity to an otherwise simple tool.

I think this boils down to what a pocket knife is to the owner. If the most use a person gets out of a knife is to flick it open and closed then maybe bearings are essential. I wouldn’t know. I gave away a spyderco mantra because I’m not a flicker and it really sucked as a tool. Part of that was the fact that it was a pita to maintain.

...what? Unnecessary complexity? I get that you don’t like them, but I don’t think they’re appreciably more complex unless you have loose bearings. If the bearings are caged, it’s the same number of parts vs a knife with nylon or PB washers.

Bearings aren’t a “gimmick” entirely because have actual purpose; in addition to making it easier to center a blade (from what I’ve read), they also reduce friction on the pivot.

It’s possible to have similarly-smooth action using non-bearing washers, but at the cost of requiring much more precise milling and engineering.

They’re not exactly tricky or more difficult to clean, either. A can of compressed air cleans out debris without the need for disassembly, and direct contact cleaning requires just as much disassembly as other knives.

I don’t think they’re universally superior, though. Only a couple of my knives have bearings, and I don’t think my Spyderco Caribbean needs them - or would even be improved through the addition of them. I think they belong pretty much exclusively in flippers, where pivot action is important to ensure full opening of the knife.

I do, however, think flippers are a superior opening method to thumbstuds and holes, as a good flipper doesn’t require you to touch the blade at any point to open and close it -and- there isn’t a place for gunk to accumulate (or get hung up on while cutting) like there is with thumbstuds.

Flippers with thumbstuds are abominations and should be destroyed.

 

[marrenmiller]

*Philsophizing*

From a mechanical standpoint, the strongest knife will be a one-piece.
If two piece-folder, you want to make it as much like a one-piece as possible, which means having the handle and blade locked together as tightly as possible.
Using a washer means the contact point between the parts is the surface area of that washer x2. Which is less surface contact than if there were no washer/bushing.
Using ball bearings means the contact point(s) between blade and handle are now 100x less than they would be with a washer/bushing, and 500x less than if there were no washer/bushing. I completely made those numbers up.

Since a folding knife is for cutting, and we want the "bond" between blade and handle to be as strong as possible, how does reducing the contact patch between blade and handle add a benefit?

I think you're missing how one approaches mechanical design. Typical design intent is not to design something as strong as possible but rather the best for the intended use, otherwise all knives would be sharpened pry bars. Since folding knives open and close a lot, people design systems that make that easier, while being rugged enough for foreseeable abuse.

Also, since we're on the topic of how "weak" bearings are: this should be required reading at this point.

 

[Comeuppance]

I think you're missing how one approaches mechanical design. Typical design intent is not to design something as strong as possible but rather the best for the intended use, otherwise all knives would be sharpened pry bars. Since folding knives open and close a lot, people design systems that make that easier, while being rugged enough for foreseeable abuse.

Also, since we're on the topic of how "weak" bearings are: this should be required reading at this point.

Additionally, folders are rarely designed in such a manner that they should be subjected to extreme force. If people want to treat it like a fixed blade, they should get a fixed blade.

I don’t know what reasonable hypothetical situation would result in physical hardware failure of any decently-made folder. For most folders, the blade is more likely to break before the handle.

I see a lot of armchair hypothesizing about deformation and tracks being worn in blades... but, curiously, I never see users actually reporting those issues developing after use - despite bearing flippers being a thing for over a decade. It’s almost as if it’s nonsense.

 

[kreole]

.

I see a lot of armchair hypothesizing about deformation and tracks being worn in blades... but, curiously, I never see users actually reporting those issues developing after use - despite bearing flippers being a thing for over a decade. It’s almost as if it’s nonsense.

I don't follow all the bearing stuff but didn't like all of Spyderco's first generation of knives have this problem? Pretty sure I saw a number of posts on just tightening the pivot a bit too much or having it come too tight causing permanent deformation

I can't think of others, though

 

[marrenmiller]

I don't follow all the bearing stuff but didn't like all of Spyderco's first generation of knives have this problem? Pretty sure I saw a number of posts on just tightening the pivot a bit too much or having it come too tight causing permanent deformation

I can't think of others, though

They did, because they used the equivalent of steel foil for their bearing races. They fixed that.

 

[Mitchell Knives]

Captured bearings are amazing and are certainly not a gimmick.

I wouldn't own or make a knife that utilized loose bearings.

 

[PURPLEDC]

Its not just marketing. But the knife needs to be properly made from the start or the benefit of bearings may never be fully realized. Are they needed? No not at all. But this is a hobby. If we limited our purchases to just needs we wouldn't have much to talk about. I do think bearings tend to get more credit than they deserve for a knives smoothness. As with most frame lock and liner lock knives the majority of the resistance is going to be from the detent ball dragging on the blade and the pressure supplied by the lockbar. But all in all they are much more than a fad and much more than marketing if properly executed in all areas not just the bearings. I would say that if your knife developed play and the pivot cant be tightened anymore then their is either a problem with the design, its execution as a whole or just that particular knife. But when the knife has a killer bearing system and a properly dialed in detent its really something special. But that swinging guillotine action is either love it or hate it. Some guys don't want the blade to just drop instantly after the lock is disengaged. Some like me absolutely love it. So I would say it really depend on you and your needs. But one thing is for sure. They are definitely not a fad and not going anywhere any time soon.

*Philsophizing*

From a mechanical standpoint, the strongest knife will be a one-piece.
If two piece-folder, you want to make it as much like a one-piece as possible, which means having the handle and blade locked together as tightly as possible.
Using a washer means the contact point between the parts is the surface area of that washer x2. Which is less surface contact than if there were no washer/bushing.
Using ball bearings means the contact point(s) between blade and handle are now 100x less than they would be with a washer/bushing, and 500x less than if there were no washer/bushing. I completely made those numbers up.

Since a folding knife is for cutting, and we want the "bond" between blade and handle to be as strong as possible, how does reducing the contact patch between blade and handle add a benefit?

You are mostly correct. If the goal for every knife fan was purely utilitarian and only one type of knife enthusiast existed. But many people like different knives for different reasons. Its not just about what Is structurally superior. Because if that really was the only determining factor we like you say would just stick with one piece knives. But this is a hobby. And within most hobbies sub interest develop. And gadgetry, speed, smoothness and aesthetics become important to some people. And some aren't looking for just the strongest folder they can get. Because you then have to ask yourself how strong does it need to be? If using a folder for its intended purpose you should be refraining from exposing the blade to lateral stress whenever possible regardless of the type of pivot it has. And with that in mind most well made bearing knives should and do survive most of what should be thrown at it. You can always make things thicker, stronger, heavier. Its just not always the goal. But also remember not all bearing systems are the same. Sometimes as many as 5 rows of bearings can be utilized providing plenty of support. And even the ones that don't such as and ikbs folder where the bearings closely revolve around the pivot are as strong as a folder needs to be. Unless of course the goal was to make a folder specifically for prying which is far from common. But if it were you would definitely probably want washers. I would discredit bearings just as I would discredit a balisong or out the front auto or even a side auto. Well maybe the last one is reduntant. Because once bearing flippers became available I had absolutely zero desire for a side opening auto. YMMV.​

 

[letsurf]

Well said. Think of the hundreds of millions of knives that have been made for work tools, all that were made without the benefit of a device intended to prevent undue wear on surfaces exposed to high speed, repetitive actions like motors, axles, machines, etc. Not that flicking doesn't happen at a high rate of speed on some of these knives, and certainly not to diminish the right for anyone to use their knife as a very manly fidget spinner while enjoying some down time.

Having carried knives for most of my life and thinking back to my first Buck 110 work knife, none of them even had washers and with a drop of 3n1, all was well. That being said, everyone has to have something to sell. To me, we are reaching the end of the road for folders, which are primarily a blade, a frame with scales, and usually some kind of detention device (a detent, backspring, lock, etc.) So really not a lot to work with. Latest and greatest steels, bizarre blade shapes, colored metals the color of peacock feathers, "tacticool", aircraft grade scale material needed to shave an ounce off overall weight, and all the rest of the new offerings seem to be getting very repetitive these days. Hard to see with such a simple design how anyone could find anything new to do to it after billions have been produced, but I have to admit installing a little Chinese bearing set was pretty original to knife design. Not sure how much it adds to the value of a "user" knife.

Robert

I still have my 110 that my dad gave me 30 years ago and a bottle of 3n1 in my garage. I feel I am constantly fighting to keep life simple and have been dreading opening up this knife as stupid as that sounds. Will probably stick to washers moving forward.

I would say the issue you are experiencing is with tops. I'd contact them for warranty.

As for bearings, I've had no problem with them, and the ease of opening I find useful in my knife usage.

I guess I don't understand the position of both the detractors and the overly zealous. Bearings aren't a huge benefit, nor even the slightest detraction for me. Generally, if I love the knife and the price is right, I'll buy it.

For me it just boils down to simplicity. I don't want to mess with getting a tray then trying to keep track of all the bearings that fall out. I guess I need to make a trip to the auto store to get some grease to put in there as well. Would just like to take it apart for a quick clean, lube, and sharpen and not worry about replacing or losing bearings.

 

[tgtodd]

Flippers with thumbstuds are abominations and should be destroyed.

I like them all.
Bearings, washers, Hinderer Tri-Way!

 

[dkb45]

Bearings are an evolution forward from washers, but kinda forward and to the side. Bearings are superior in some ways and inferior in others. They reduce the necessary tolerances on the pivot and in most knives allow the pivot to be fully tightened to the point of no play but have extremely free action because the bearings roll not drag like a washer. They are technically easier to clean, requiring less lubrication and being able to be ran dry and still give decent action, or working fine with oil or grease, where washers usually respond best to grease and oil will work its way out. They are more prone to damage from overtightening and are more vulnerable to debris clogging them up. If ran dry, bearings are capable of rusting, although it is mitigated with ceramic.

Overall I think bearings are an improvement over washers, but they aren't the end all be all of pivot friction reduction technology. There's stuff like Protech and Hogue uses that has a completely washer free design, which is another side evolution. The tech is ever moving forward and innovation will likely eventually render bearings obsolete.

The real improvement we need to talk about because there is no argument to be had on it, and all manufacturers need to get on board with, is ceramic defend balls. Steel balls eventually wear out, ceramic has a nearly indefinite lifespan. The lock will likely wear out before the detent ball. I've had multiple knives have a steel ball that ran flat, and once they do the detent turns to garbage, and only some manufacturers will warrant a worn out detent ball. The cost difference is absolutely negligible, which the ceramic balls are substantially more expensive you're looking at a few cents a piece tops. Spyderco is finally starting to switch to ceramic on some of their CQI knives, and virtually all Chinese knives come with ceramic detents. Get on it!

 

[Natlek]

*Philsophizing*

From a mechanical standpoint, the strongest knife will be a one-piece.
If two piece-folder, you want to make it as much like a one-piece as possible, which means having the handle and blade locked together as tightly as possible.
Using a washer means the contact point between the parts is the surface area of that washer x2. Which is less surface contact than if there were no washer/bushing.
Using ball bearings means the contact point(s) between blade and handle are now 100x less than they would be with a washer/bushing, and 500x less than if there were no washer/bushing. I completely made those numbers up.

Since a folding knife is for cutting, and we want the "bond" between blade and handle to be as strong as possible, how does reducing the contact patch between blade and handle add a benefit?

I m with you on this .....No washers ,no detent ball I used on this folder .Complete knife is made from HSS cobalt steel /64-65 Hrc/ liners are 2.2mm blade is 3mm except pivot /6mm dia./ which is /hardened/ stainless ball bearing steel .Lock engage slightly more then 50 % , rock solid no play anywhere . I adjusted friction between blade and liners so it can stay in close position. ... that is all I need from folder knife .If I mount thumbstuds it will be easy to open with one hand but I don t need that ....But nothing wrong with bearing if everything is done right which mean steel on steel .I don t understand how can ball bearing turn on soft titanium and how long that can last .

 

[Mrgauth]

Bearings are an evolution forward from washers, but kinda forward and to the side. Bearings are superior in some ways and inferior in others. They reduce the necessary tolerances on the pivot and in most knives allow the pivot to be fully tightened to the point of no play but have extremely free action because the bearings roll not drag like a washer. They are technically easier to clean, requiring less lubrication and being able to be ran dry and still give decent action, or working fine with oil or grease, where washers usually respond best to grease and oil will work its way out. They are more prone to damage from overtightening and are more vulnerable to debris clogging them up. If ran dry, bearings are capable of rusting, although it is mitigated with ceramic.

Overall I think bearings are an improvement over washers, but they aren't the end all be all of pivot friction reduction technology. There's stuff like Protech and Hogue uses that has a completely washer free design, which is another side evolution. The tech is ever moving forward and innovation will likely eventually render bearings obsolete.

The real improvement we need to talk about because there is no argument to be had on it, and all manufacturers need to get on board with, is ceramic defend balls. Steel balls eventually wear out, ceramic has a nearly indefinite lifespan. The lock will likely wear out before the detent ball. I've had multiple knives have a steel ball that ran flat, and once they do the detent turns to garbage, and only some manufacturers will warrant a worn out detent ball. The cost difference is absolutely negligible, which the ceramic balls are substantially more expensive you're looking at a few cents a piece tops. Spyderco is finally starting to switch to ceramic on some of their CQI knives, and virtually all Chinese knives come with ceramic detents. Get on it!

TOTALLY agree on the detent ball thing. I am to the point that I will not buy a knife without ceramic.

As for bearings, I don’t think they are a gimmick at all. Just someone trying to innovate. Knife folks probably always referenced the smoothness of this knife over that one for years and someone finally went, “hmm, wonder if a ball bearing knife would be smoother?” Rest is history.

 

[craytab]

For me it just boils down to simplicity. I don't want to mess with getting a tray then trying to keep track of all the bearings that fall out. I guess I need to make a trip to the auto store to get some grease to put in there as well. Would just like to take it apart for a quick clean, lube, and sharpen and not worry about replacing or losing bearings.

Caged bearings all the way. Uncaged bearings are something I wouldn't buy for the exact reason you mention.

 

[soc_monki]

I have knives with washers and knives with bearings. They are all strong and hold up to knife duties. I don't baton or pry with them so that point is moot. But bearings are not weak in any way unless the mechanism is underdesigned (like the early spydercos, apparently that tops, and cheaper Kershaw pivots with thin washers).

Personally I don't care what kind of pivot a knife has as long as it works well, is solid, and I can service it. I like tinkering, I like maintaining my stuff. No loose bearings (would be a nightmare) but caged is no hassle at all.

 

[Tseg]

I currently only own Chris Reeve and Shirogorov knifes, both with different deployment mechanism philosophies.

• None are worn out or have broken < this is the most important point ---- I had a Spyderco but it was stolen so I no longer buy Spydercos
• My "openings per day" average is significantly higher with Shirogorov, thanks to the enjoyable flipper/bearing system
• ^^^ I suppose this is both good and bad about Shirogov… my Utils per day are higher with Shirogov, but maybe will only last me 3 lifetimes instead of 4 due to the increased wear?
• Stuck on a desert island, I believe my CRKs would be more durable under abusive use
• Currently my EDC is my NeOn Zero... longer blade (displacing my Small Inkosi, my prior EDC for 10 straight months), slices better, lighter, thinner, funner
• If I bend a CRK washer, I must go to CRK for replacement. If I lose a Shirogorov bearing I can buy 100 1.5mm high quality grade bearings for <$10 delivered in 2 days through a prominent shopping website

In summary, marketing gimmicks add value, if only emotional value. But ball bearings actually do something. They make blade deployment feel different than washer bearings. So I argue ball bearing systems are not a marketing gimmick, but maybe my multi-row-bearing-system is a marketing gimmick? Nonetheless, I specifically sought that out at a cost premium over a SRBS and gain emotional enjoyment from it daily. The beauty with hobbies is you can justify anything to yourself.

 

[marrenmiller]

For me it just boils down to simplicity. I don't want to mess with getting a tray then trying to keep track of all the bearings that fall out. I guess I need to make a trip to the auto store to get some grease to put in there as well. Would just like to take it apart for a quick clean, lube, and sharpen and not worry about replacing or losing bearings.

Then try one with caged ball bearings. They're a single unit so you can't lose the individual balls. Knives with caged bearings come apart and go back together exactly like knives with washers.

 

[Hologram]

...and gain emotional enjoyment from it daily. The beauty with hobbies is you can justify anything to yourself.

There ya go! If all someone wants is a good work knife, they can probably get by with one or two in their entire lives, but most of us are collectors to some degree and collectors tend to collect what they enjoy. If that involves the feel of a good bearing system, so be it.

Use a different knife if you’ll be twisting and prying. The right tool for the job, and most of us have multiple tools to choose from.

 

[Sergeua]

I think its easier to make a budget flipper with caged bearings rather than going the washers route. The result will be better flipping action with less side to side compared to washers. Your tolerances have to be higher to pull off the same with budget production on washers. So I think bearings are more forgiving and are faster to assemble for producer, as they don't have to play with pivot much to get it right in every single case and again the results are more consistent.

 

[robgmn]

I think you're missing how one approaches mechanical design. Typical design intent is not to design something as strong as possible but rather the best for the intended use, otherwise all knives would be sharpened pry bars. Since folding knives open and close a lot, people design systems that make that easier, while being rugged enough for foreseeable abuse.

Also, since we're on the topic of how "weak" bearings are: this should be required reading at this point.

This is philosophy, and not me trying to bash or berate ball bearings in any way. I've considered buying a knife with bearings just because they exist and I think it's interesting. I have a carbon fibre handlebar on my bike for the same reason. No weight savings, no strength increase that I'll ever exploit, BUT IT'S COOL.

Here's where I see a flaw in your argument against me: "Typical design intent is not to design something as strong as possible but rather the best for the intended use".
A knife is a tool used for cutting. You always want the knife as strong as possible for your own safety. How does having ball bearings between the blade and handle make the knife better at cutting? How does it insure the strongest/safest tool?Opening and closing the knife should 1/10 of a second of "use". The real purpose (cutting) should be far longer, and that's where you would normally focus your design efforts for a utilitarian product.

Now, maybe you have a job where you open, slice, close, open, slice, close all day long. THAT might be a good place for the benefit of bearings making that 1/10 of a second as enjoyable as possible (insert your own juvenile humor here ). Or, maybe you use the knife like a fidget spinner, or have a butterfly knife. Both good places for silky smooth action.

On a utility knife? Nope. It's antithetical to the whole philosophy of making the best & strongest tool possible.
Going from full tang to partial tang on a fixed blade is a compromise.
Going from fixed to folder is a compromise.
Going from folder to folder with bushings is a compromise.
Going from bushings to bearings is a compromise.
It's just the way it is from a mechanical/engineering standpoint.

Does it really make a difference? For all practical purposes, I'm sure it doesn't. I know for a fact that none of my knives except perhaps one are ever pushed close to their capability and are thus over-designed for my purposes. I'm sure a knife with bearings would be the same. I'll bet most people are the same (witness how many people sell their EDC that looks like it just came out of the box).

But, I'm not talking about what usually happens. I'm talking about the technical reality. Two different worlds.

 

[cbrstar]

I bought some inexpensive CRKT's the other day and one of them was a Fossil which is my first ball bearing knife.
It does feel a lot more solid then the other crkt's and the detent seems nicer. But I noticed there are groves in the blade from the bearings. I can only assume the bearings are not rotating therefore they are not doing their job.