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Folding knives share the same basic requirements of other knives. And I could go over all of them, instead, the main article body will focus on the ones unique to folding knives. But first! Ask yourself these 3 questions.
Pick up a pocket knife. ------------------------------------------------------Is it comfortable?
Open it.-------------------------------------------------------Does it lock solidly?
Ask yourself.---------------------------------When you cut with it... Will it hold an edge?
Through all the hype, these 3 things are what really matter. Years into owning a pocket knife, these are the 3 things you will remember, and it’s appearance is what will cement it fondly in your mind. Even if ugly! You ever have an ugly friend who you adore, because their personality is solid gold? A quality pocket knife is like this, and appearances compliment quality, while in no way requisite.
And just like that friend, a quality pocket knife will stand by you for years, perhaps a lifetime. Do not accept less. If a knife wears out quickly, losing the affore-mentioned qualities, something is amiss, and it’s quality is a fail.
Unlike your pal here, you do get to pick your pocket knife’s appearances. So do so. Just remember the 3 things foremost, and do not let good appearances lure you into a poorly made knife purchase.
SO many other things affect quality in a knife, but most of them in some way fall down to these 3, while others stand apart as aspects which might be nice to have.
I’m assuming you’ve already gone through my “effective knives” article, so you know what the basics are.
Specifically you know to check for blade hardness, material choice quality, comfort, etcetera. If not, check it out here > Effective Knives
First off, please don’t buy a folding knife for self defense. Fixed blades are for self defense. Any other choice is from necessity, or folly. They can fold under stress induced failure, or grip and twist induced disengagement of the locking mechanism in ways you may or may not have anticipated. This could cause the blade to close on your fingers under a lot of force! While modern folders in the higher quality brands have gotten much better about this, a fixed blade remains the best choice for a personal defense knife.
Theoretically a quality folding knife won’t fold on you, but you don’t know that. Theories suck in reality more often than they work. If you must have a "tactical folder" I can think of none better than Cold Steel Triad Locking folders.
That said, folders make delightful daily use knives, and are incredibly convenient compared to not having a knife. Folders are their own sheath, and whereas with a fixed blade you would have to carefully re-sheath by visually guiding the tip back into it’s sheath without cutting yourself or the sheath, folders merely need to be unlocked, then closed while your fingers are clear. This unique aspect of folders makes a massive difference in day to day use. The ability to fold speeds up replacement when done, because fewer actions are needed to stow the blade. An unlocked blade can only move in 2 directions on it’s pivot; open or closed.
The fact that a knife folds tends to indicate it is NOT for combat. This mental note, which is surprisingly prevalent, usually has a profound effect on the people around you. In other words, folders usually come off as more benign and utilitarian, and are less likely to put people at unease. So even if you are wearing a nice fixed blade knife, it makes more sense in daily tasks to reach for a folder if practical. Whether for light duty use or emergencies, any blade is better than no blade, so I encourage people who otherwise would not wear a knife, to at least have a small folder, while those who have a fixed blade, may consider enjoying a folder for both convenience and reduced unwanted attention.
Folders are their own sheath, and whereas with a fixed blade you would have to carefully re-sheath by visually guiding the tip back into it’s sheath without cutting yourself or the sheath, folders merely need to be unlocked, then closed while your fingers are clear. This unique aspect makes a massive difference in day to day use because folding speeds stowage, and fewer mistakes can happen. An unlocked blade can only move in 2 directions, open or closed. The same is a pocket knife’s Achilles heel… That folders fold, leads to several problems. Knowing what these problems are, leads to clearer solutions and understanding. Without further ado these are____
1 Failure of the pivot, locking mechanism, frame, or blade tang, whether from breakage or flex induced disengagement will allow the knife to fold on you during use if any downward pressure on the blade is present during failure, including during a stabbing motion. A lot of pressure is usually needed to cause lock failure, and that same pressure would definitely cause the blade to fold. So you can see quality and intended use is relevant to your safety.
2 Folders are less comfortable due to the blade slot, pocket clip, and (often) open back design.
3 A weak or bent pocket clip lets Mr. blade pull the disappearing act on you.
4 Cheap or non existent blade detention will let your knife open, causing you injury.
Lockbacks normally don’t have this issue because they actively spring closed when folded. This issue is more prevalent in flipper type opening blades, and anything designed to open quickly through centrifugal force (a quick flick)
Avoiding these issues is fairly simple.
Start with price. Under 25 bucks: pass. I recommend at least $25 to go pocket knife shopping, preferably $50 or more. but let’s be fair. $25 can net you a working knife that won’t fold on you during correct usage, holds some kind of edge, looks decent, and has a working pocket clip. How did I determine this price point? I already knew from experience, but… I checked on Blade HQ, sorting by folding knives, priced low to high, and checked every page till I consistently saw folders at least 3 inches, some of which I would buy if budgeting for a basic folder.
I skipped all the Brownings, Benchmarks, folding shotgun shells, slip joints, Remmingtons and Schrades. They are all junk as a rule. (Never a buy a slip joint, it’s a great way to get cut) I also skipped the miniature folders, Smith & Wessons, Camillus, Bear and Sons, and a couple funky Kershaw bottle opening knives… If you haven’t noticed by now, firearm manufacturers love to have junky Chinese companies make trinket knives for them. Usually some liner lock between 1 and 3 inches with a massive wobble, horrible steel, and black painted blades. There are typically no warranties, the gun maker does not make the knife, and the knives do not hold up to real use. I did see a few functional knives in that range, but picking at random would be like playing the lottery. I have the experience to do so, and one day, you will too. By that time you will be interested in much higher quality knives, and you will be very glad you didn’t throw away 20 bucks on repeat for cheap knives.
The following knives were definitely consistent exceptions. Opinel knives. A French company with a knife on which you turn a slotted ring to unlock, open, close and re-lock. These little wood handled creatures are much loved, come in different sizes, and have quality plain carbon steel blades on the cheap. Buck Bantam folder 284s Good steel, light weight, and light use knives. A couple of different small Kershaw knives which can be relied upon. A few low end Boker lockback knives which though cheap, are solid, and the KA-BAR Dozier folding, (An approximately $20 lockback with decent heat treat, a functional lock, and effective flexible handle scales) Minimum pricing handled. If you are truly broke, go strait to these knives, and pick one out!
lets move on to__>>>
#1 Failure of the pivot, locking mechanism, frame, or blade tang. If you’ve ever wiggled a cheap pocket knife to see why it’s blade feels loose, only to be startled when the liner lock got out of the way and the blade folded towards your finger, you are not alone. This sad story is cheap manufacturing. The only purpose of this knife was to steel a few dollars from someone. Of all locking methods, the liner lock seems to have been singled out for mass crappy production in China. I’ve also seen lockback folders that would close on you, but they are obvious because they don’t have metal anywhere in the handle or frame, probably cost under $20, and flex visibly if you press the open blade sideways with any force.
No matter what lock you get, make sure the knife feels solid. Lock the blade open, grip the handle firmly, and carefully pinch the blade’s spine and try to wiggle it vertically and laterally. This is best done while wearing a glove! There should be little to no wiggle, and almost no flex either. Basically the blade should feel firmly in place, and not leave you second guessing. Zero wiggle is much preferred to “little”, but I’ll be darned if my 1991 Buck 112 Ranger isn’t solid, and it always wiggled the tiniest bit. You want a blade solid in all directions, up, down and sideways. I would also note you can hold a pocket knife handle from either side, (don’t put your fingers over the blade slot!) and rap the blade’s spine on a piece of wood or plastic (gloves are great here!). If it doesn’t close, and feels solid, chances are much better it won't ever close on you. You can’t usually do this with a new knife in a store, because, obviously you could damage someone’s furniture or new knife.
Locks should behave as follows below when the blade is opened. (I will include links to each type for design and operation information).
Liner locks: The liner tab clicks in firmly and instantly, preventing any wiggle, and shows no signs of flexing, sliding, or slipping back into the un-locked position. The liner should contact the blade’s thickness at least 50% if not fully. Compression Locks are Spyderco’s enhanced liner locks.
Frame-locks: This is a close cousin to liner locks. The difference being frame locks have a springy piece of the frame come over and lock in behind the blade. These rarely have issues with the lock, just check for wiggle, and make sure at least ½ the blade thickness is locked in with the frame tab.
Lock-backs: Lock-backs should click audibly, and engage suddenly with force in the last few degrees as the knife opens. The lock release tab on the spine should have to be pressed most of the way before blade release occurs. Triad Locks are Cold Steel’s enhanced lock-backs.
Axis Locks belong to Benchmade (as a trademark) and the utility patent has expired, so we’re seeing these pop up on multiple other brands. The Omega springs in them occasionally fail, but so long as they are functional, Benchmade knives tend to lock solidly. Replacement springs are available.
Ball bearing locks belong to Spyderco, and I am not aware of any issues with them.
There are other types of locks, but the thing to keep in mind, is just make sure they lock up solid.
If you have any questions about these locks, just grab a piece of your favorite search engine, and put it to work. Nothing like visual reference or a good ole video review!
What about the other types of failures? In general, you have no way to test the blade’s tang, either for steel quality, or really any other practical test. However, you can look at the tang and see if it’s been machined cleanly. A sloppily machined tang with crude tool marks, seemingly inconsistent gaps, or any sort of ill fit, is suspect. I usually don’t analyze this much, and a good lockup will usually cover this for you; But! I like to have a glance, even if after I buy the knife, to make sure it’s not super delicate compared to my other folders. A folding knife’s blade tang is that tiny cut out portion on the back: the general area that rides inside the knife handle. A few things happen here. The hole drilled in the center allows the tang to rotate around the pivot. A slot in the top-back, in various shapes, allows the lock to engage if it’s an Axis Lock, Lockback, Triad Lock, or certain others. Frame and Liner locks will engage the far end, where they slide behind it, preventing the knife from closing. There may be a tiny semi-spherical divot in the side, allowing a ball detent to pop out and hold the blade closed with a small amount of force. I love ball detents, as they are usually both safe and reliable. If your knife is a liner or framelock, the top-back will have a slot or flat spot where the tang can rest against the stop pin. This is the pin that prevents the blade from folding backwards.
Blade pivot failure. I have 2 issues here. 1, is really tiny pivots which could potentially break and fail. Even my Spyderco has a tiny pivot, and that’s just one more reason not to trust a folder for a fixed blade task. Just assume the pivot will not stand much abuse, and leave it at that. 2, something you can actually make a choice about, is pivot adjustability and type.
There are 3 basics types.
NON adjustable pivots, which are usually ok, if the knife if built solidly, and there is no blade play, at least it’s not likely to work loose. I actually tend to prefer non adjustable pivots.
Adjustable pivots have 2 basic types:
Poorly made pivots that “adjusts” in one turn or less, or which “adjust” by turning a circle on repeat, without ever truly locking down... This is really bad, because they invariably work around to the “loose” position, sometimes after only a couple of openings. Obviously these will have blade play. What’s NOT always obvious, is if they don’t have blade play right away, they can develop it after a short period of use. User reviews are your friend here. It can be hard to tell without disassembling the knife, how or if a blade’s pivot adjusts. In general, I find nylon washers are usually paired with the poorly adjustable type of pivot. These are “no go” knives.
Fully adjustable pivots. These involve a pivot pin which is often more like a Chicago screw. That is, the pivot drops in from one side, and screws in from the other. The drop in piece has a flat side which prevents it from turning while you tighten the other. Alternately, both sides may tighten. These work, but are annoying, because you need a vice, both hands, and 2 tools to get the job done, sometimes 2 of the same tool. So obviously, I prefer the “drop in one side, tighten on the other”. Fully adjustable pivots usually have at least 3 turns adjust-ability, and should be secured with blue thread locker to prevent backing out. The good thing is full adjustment usually allows you to remove all lateral blade play, and increase or decrease friction on the opening action. However, some less expensive blades may have to be adjusted loose on purpose, (allowing blade play) in order to easily flick or flip them open. This is the deciding line between cheap and decent flick-able folders.
Frame failure. Frames weak points are the spacers and assembly screws, and this includes the blade pivot, and stop pin. Metal frames are usually unlikely to “fail” although any poorly made frames, especially un-lined, non-metal frames, can twist, yielding lock failure or a dangerous spring loaded cutting situation under heavy use due to handle and blade flex. To be fair, it can be said that handle scales (attached with even tinier screws) are part of the frame. With this view, they have even more weak points. A common place for frames to “fail” whether by outright breaking, or flexing enough to allow pieces to pop apart or slip, is the blade to frame junction. Yep, that spot where the tang rides in the frame with bearings, lock, stop pin, and pivot all present. This is where all the force from the handle is transferred to the blade, and vice versa. Any flex will likely occur here, and blade play of course, can only occur here. If something flexes too far, or incurs enough stress, the lock could come undone, the pivot pop out, the stop pin could break or pop out…. Basically anything! Look for frames with more connecting material between the 2 sides, and larger/more screws holding everything together. You want frames with liners, that is, you want steel, aluminum, or titanium lining inside the frame, on both sides of the blade slot.
#2 Ergonomic issues. Pocket knives have 2 folding specific issues here, blade slot and pocket clip.
Pocket clips can be gotten around fairly easily. If clips annoy you, merely buy a knife with no pocket clip, remove the pocket clip, or (if it’s a really nice knife) you may have more than one pocket clip position, and up to 4. In this case, switch where the clip is mounted. If you remove a clip, your options are pocket the knife, place the knife in a bag, or buy a sheath. Leather or nylon belt type is the usual standard. You can even buy neck carry Kydex sheaths for some pocket knives, and you can always have one made.
Let’s address blade slots. Slots cause discomfort! If you grip a pocket knife tightly, you will notice your fingers get “bitten into” by the edges of the knife slot. This can be mitigated by A: chamfered liners which don’t “bite” as sharply. B: thicker handle scales which give your fingers more support. C rubber grips that extend past the liners to cushion the edge, and D (or maybe A) liner locks often have locking tabs which extend past the edge. Those hurt! Always check a knife’s side profile if you cannot touch it first hand, and see if the locking tab extends past the lowest point in the handle scales (except the cut-out for closing). You can always opt for a different knife design. Consider opting for a NON liner locking knife. Liner lock knives, (and their close cousin frame locks) both have this problem because the tab must be accessible to release the lock. This often causes poorly thought out ergonomics. This is doubly the case with frame locks because the frame must be exposed to work, so a frame-lock usually has only 1 handle scale, and the other side is bare metal. Some people are ok with this, some are not. The shapes used however, are (again) often poorly thought out. And lastly. Most modern folders are open frame design. This means the spine of the knife handle consists of the handle scales sandwiching open air. This creates discomfort in the exactly same way the blade slot does! Of course it was touted as design advancement when it first came out! Thicker handle scales once again mitigate this, as do properly chamfered ones. Lock back and Triad Lock designs once again do not have this problem. If open handle designs bother you, search for knives with “backspacers”. These have a piece of handle material that fits perfectly, sealing up part or all of the exposed hollow center-line.
#3 Pocket clip issues can be resolved by testing the pocket clip prior to purchase, or checking reviews prior to ordering. Remember many online orders can also be sent back or refunded if you follow the rules. Your clip should hold itself firmly against the knife scale, and when pulled a tiny amount and released, should snap back with vigor, and make a clicking sound. If yours does not snap back, or snaps back weakly, the clip is no good, and the knife should be returned. Clip the knife on your pocket and give it a tug. It’s easy to tell when it doesn’t retain well enough. Look at the attachment point; quality pocket clips will have between 2 and 4 screws. 1 screw is not enough on most designs to reliably and effectively hold a clip on, and will strip out eventually. There are exceptions to this, as some knives have an over sized screw. Keep in mind most pocket clip screws are delicate, and care should be used when tinkering with clips to ensure you don’t over tighten the tiny things.
#4 Blade detents are a huge issue, but a quick solution. Boycott knives which do not have them.
Detents merely hold the blade shut with a small amount of force. These detents can be a variety of things. The most common one is a spring loaded ball detent, similar to what you would see on a ratcheting socket wrench anvil, but much smaller. Lock-backs close under the reversed force of the bar spring used to lock open, and pretty much all of them do this effectively. Just check and see if your knife has “detent”. Detent can be a verb or a noun, so you grammar Nazis just hush... Some knives “detent” with just friction. This is not acceptable, and as the knife wears in, or the adjustment screw loosens, you will have problems. A few people demand light or nonexistent detents because they enjoy super smooth flipper action. This is foolish, and a great way to get cut unawares. I would like to add, that a snug detent actually allows force to build when you press your flipper tab, allowing flipper knives to more effectively flip open.
I would like to wrap up with some basic tips, and more general pocket knife shopping information.
Liners and bolsters affect how sturdy a folder is. Some folders these days don’t have metal liners under the handle scales. Some of these are merely cheap, and poorly built, while still others (Like my Cold Steel Grik) are glass fiber reinforced mini-beasts. You can check reviews, ask customer service, or look really closely in photos to determine if a knife has metal liners. Bolsters are great, but not necessary with modern engineering as long as the knife is made of metal, has liners, or is glass fiber reinforced.
When ordering online, pay attention to return policies! Note whether returns are allowed, whether you can return after removing the wrapping and handling, and who pays return shipping. At some knife specialty stores they charge a “re-stocking fee”. I dislike this, and usually avoid these stores. If I have an issue, I should not be charged for having that issue resolved. Period.
Check every detail. It’s so easy to think you’d like a particular knife and order it, only to discover you overlooked something very important, like the fixed position pocket clip that’s exactly where you don’t want it, or the slick aluminum handle scales that will be a real issue during all weather use or hunting. I’ve ordered a knife before only to discover I overlooked blade length!
Ignore salesman in physical stores. Salesman do not know anything about knives, and they will feed you a lot of BS if you let them. Politely use exactly ZERO% of their information. I’m sure there are rare exceptions to this, but I’m not holding my breath. Besides raw technical specs, a salesperson is usually wasting their breath.
Pay attention to handle scale shape. Most folders have completely flat handle scales. This is not comfortable for heavy use knives, and if you use your knives a lot, this flaw will show. If you require a heavy use knife, then seriously consider skipping folders altogether, and buying a small fixed blade. Fixed blades are available in all shapes and sizes, more so than folders, and will certainly meet your heavy use needs.
Avoid funky blade shapes and features that cannot be sharpened on flat stones. No form of inside curve can be sharpened on bench stones, necessitating a rod system. If you have a rod system, that’s great! If you don’t, look at the prices of sharpening your knife, before you opt for a knife you cannot yet sharpen.
I know this is in violation of the above, but really large inside curved blades with a shallow curve, can often be sharpened with a narrow stone. The edges of the narrow stone will be sacrificial, and eventually wear in to the the blade's average curve.
Avoid serrations unless you have a reason for wanting them. Serrations are annoying to sharpen, and use up precious edged real-estate on your knife. If you actually use serrations a lot, consider getting a separate all serrated knife for these tasks. You will thank yourself often.
Consider an alternative to thumb studs, I do like flipper knives, thumb holes, or manual “pinch and open” blades. Thumb studs cut up pants pockets, obstruct sharpening, and catch on everything… They also happen to be the most popular form of knife opening… I like thumb studs, but if I now prefer flipper knives. The thing is, not all knives are, or can be the flipper type, and Spyderco owns the patent on cutting round holes in blades for opening… So unless you want a Spyderco, you are left with flipper tabs and thumb studs/discs for the most part. This, in my opinion, despite all the other hype, is one of the best arguments for purchasing a Spyderco!
By the way, the best argument for NOT owning a Spyderco is also the thumb hole... The hole edges tend to catch on cardboard, and I feel make horrible cardboard slicers.
You can also find thumb studded or disc opening knives which have the stud/disc recessed as close to the handle as possible. This makes opening slightly more difficult, but removes them from the cutting path, and I feel is a better option for utility focused folders. Since I'm not a "tactical folder" fan, you can see this applies to most folding knives.
Here're a smattering 3 of my favorite folding knives.
Kershaw Emerson CQC-6K Combat Wave frame lock
(Makes a great large, heavy use EDC)
KA-BAR Dozier Folding Hunter D2 liner lock
(An inexpensive lightweight, light duty knife)
Artisan Cutlery Arroyo Flipper liner lock
A nice looking
Benchmade Mini Griptilian
(a nice all around 2.91 inch blade, tough with classy looks and premium steel)