The first assisted opening mechanism was invented by renowned custom knife maker Blackie Collins based on the strut featured in his Ducati motorcycle and is similar in function to an automatic opening mechanism. However, unlike automatic opening knives which enable the user to open the blade by depressing either a button or a lever located on the side of the knife, an assisted opening mechanism requires the user to employ either a thumb stud, a thumb hole, or a flipper to manually open the blade approximately 30 degrees before the torsion springs take over and open the blade the rest of the way.
Folding Knives Buyer’s Guide
When choosing an assisted opening folding knife, there are several aspects of folding knife design that you should consider. For instance, the type of steel the blade is made from is an important factor because most every-day-carry knives are now carried in the user’s pocket instead of in a belt pouch. Also, the closed length of the knife, as well as its blade length, are both important factors for the same reason. In addition, because many users have a distinct preference for folding knife designs that they can open and close with a single hand, the type of opening and locking mechanism a folding knife has should also be considered. Thus, below you will find information that explains each of these aspects to help you choose the assisted opening folding knife design that best suits you.
- Blade steels – The first step to choosing an assisted opening folding knife is to choose between a blade made from a stainless steel or one made from a high carbon Plain Tool Steel because most folding knives are now carried in the user’s pocket rather than in a belt pouch where they are subjected to constant perspiration from their owner’s body. Consequently, stainless steels are a far better choice than high carbon Plain Tool Steels due to their high Chromium content which enables them to resist corrosion even though Plain Tool Steels are often tougher and easier to sharpen then Stainless Steels are. So, when purchasing an assisted opening folding knife, the type of steel the blade is made from is an important aspect to consider.
- Rockwell Hardness – In addition to the type of steel the blade is made from, the Rockwell Hardness of the blade is another factor that should be considered because it will play a large part in determining the blade’s ability to hold an edge. Therefore, the Rockwell C scale is commonly used to measure the hardness of blade steels and, the higher a knife blade’s Rockwell Hardness is, the better it tends to hold an edge. However, it should be noted that the disadvantage of a hard knife blade is that it is more difficult to sharpen and that harder blades have a greater tendency to break when subjected to lateral pressure. Consequently, when choosing a folding knife for general purpose use, blade steels with a Rockwell Hardness of 55 to 60 are a good choice.
- Closed Length – Another important factor to consider when purchasing an assisted opening folding knife is the closed length of the knife because most users today prefer to carry their folding knives in their front or back pocket rather than in a belt pouch. Therefore, if you choose to carry your folding knife in your front pocket, then you might want to choose a shorter design but, if you instead prefer to carry it in your back pocket, then you might prefer a longer design. But, you should also be aware that while folding knives with relatively short closed lengths are convenient to carry, they often do not provide a grip that is as secure or as comfortable as folding knives with longer closed lengths do.
- Blade Length – In addition to the closed length of the knife, the length of the knife’s blade is another aspect that should be considered because the length of the blade affects both the length of the cutting edge and its utility. Therefore, while some users prefer folding knives with relatively short blades, others prefer longer blades because a mere one-half inch of additional length can make a significant difference in the knife’s performance as a utility tool. Consequently, while some users prefer folding knives with blades as short as 3 inches, others have a distinct preference for blades that are at least 3.5 inches in length and, some users prefer blades that are even longer.
- Assisted Opening Mechanisms – Nearly every folding knife manufacturer in the market today has developed their own version of the original assisted opening mechanism designed by custom knife maker Blackie Collins. However, although the various manufacturers would have us believe otherwise, they are all essentially the same in that they all operate on the same principle of employing either a leaf spring contained in the back of the knife or a coil spring coiled around the pivot pin and contained in a hole in the liner underneath the handle scales to assist the user in opening the blade. Therefore, in order open an assisted opening folding knife, the user simply applies pressure to either a thumb stud or a thumb hole to manually open the blade approximately 30 degrees at which point the spring takes over and automatically opens the blade the rest of the way.
- Locking Mechanisms – Although nearly all folding knives used to employ either a Liner Lock or a Back Lock locking mechanism, folding knife designers have since developed numerous different types blade locking mechanisms. However, while the mechanical operation of the various types of locking mechanisms varies from manufacturer to manufacturer, the main difference that you need to be aware of is that some types of folding knife locking mechanisms such as liner locks and piston locks enable the user to release the blade with a single hand while others such as mid-locks and back locks require two hands to release the blade. Furthermore, many folding knife manufacturers like to emphasize the strength of their proprietary new locking mechanisms but, this is somewhat misleading because little to no stress is actually placed on a folding knife’s locking mechanism when performing every day cutting tasks. Therefore, rather than be mislead by the relative strength of a folding knife’s locking mechanism, you should instead focus on how well it will handle wear and whether or not it will automatically adjust to compensate for it in order to keep the lock tight.
The Top Five Assisted Opening Knives under $100
Because there are so many different folding knife manufactures in the market today who produce so many different designs, choosing a single assisted opening folding knife from among the many can be a confusing task for most people. Therefore, below I have listed what I feel are the top five assisted opening folding knife designs with MSRP’s that are less than $100 in order to save you the trouble of sorting through all of the various manufacturers and designs. In addition, because most people carry a folding knife for utility purposes rather than for tactical use, each of the knives that I have chosen feature moderate rather than radical blade designs which are imminently well suited for the purpose of day-to-day cutting tasks rather than for use in tactical situations.
OKC RAT Model 1A
- Blade Thickness: 0.095"; Blade Grind: Full Flat Taper; Blade Finish: Satin; Blade Color: Silver; Blade Material: AUS-8 Stainless Steel; Blade Length: 3"
- Handle Material: Nylon 6 Handle Color: Black; Lock Type: Liner Lock
- Closed Length: 4.1" (10.4 cm); Weight: 2.8 oz.
The RAT Model 1A was designed by Randall’s Adventure Training (and is produced under license by Ontario Knife Company) to be a folding utility knife for both outdoor use and every-day-carry. Featuring a closed length of 5 inches with a 3.5-inch blade and a weight of 3.5 ounces, it also features a drop point blade design made from AUS-8 (which is a Japanese, high carbon, Stainless Steel) with a Rockwell Hardness of 55-56 HRC and a flat grind. In addition, it is available in your choice of a plain or partially serrated edge with either a satin or black epoxy coated finish. In addition, it also features an assisted opening mechanism and a thumb stud combined with a Liner Lock locking mechanism. Plus, it includes one the most ergonomic handle designs on the market with an open back and stainless steel liners with handle scales made from Nylon 6 which are available in several different colors. Plus, it includes a reversible, tip-up or tip-down, steel pocket clip.
|(+) One hand opening and closing||(-) No pocket clip|
|(+) Robust construction|
|(+) Good choice of blade steel|
OKC Utilitac 1A
The Ontario Knife Company Ulitilitac Model 1A was designed by renowned custom knife maker Joe Pardue (and is produced under license by Ontario Knife Company) to be a folding utility knife for both every-day-carry and tactical situations. Featuring a closed length of 4 inches with a 3 inch blade and a weight of 4.4 ounces, it also features a swedged drop point blade design made from AUS-8 (which is a Japanese, high carbon, Stainless Steel) with a Rockwell Hardness of 56-58 HRC and a hollow grind and is available in your choice of either a satin or black epoxy coated finish. In addition, it also features a thumb stud and OKC’s Tactical Assisted Opening mechanism which was also designed by Joe Pardue combined with a Liner Lock locking mechanism. Plus, it includes a very ergonomic handle design with stainless steel liners and handle scales made from G10 and, it includes a reversible, tip-down only, steel pocket clip.
|(+) AUS-8 stainless steel blade||(-) Blade is a little short|
|(+) Liner Lock locking mechanism|
|(+) One hand opening and closing|
- 3.5 INCH STAINLESS STEEL CLIP POINT BLADE: The SOG Aegis straight edge tactical folding knife is a field-tested EDC knife, hunting knife, camping knife and rescue knife; measures 4.75 inches in closed length
- 3.1 OUNCES W/ GRN HANDLE: This everyday carry assisted folding knife includes a glass-reinforced nylon grip; pocket folding knife handle requires zero upkeep and is nearly indestructible
- SOG ASSISTED TECH (S.A.T.) & PISTON LOCK: One of the fastest opening knife systems ever; survival pocket knife opens single-handed and Piston Lock secures the blade
A truly graceful folding knife design, the SOG Aegis is an excellent choice for an assisted opening every-day-carry knife. Featuring a closed length of 4.75 inches with a blade length of 3.5 inches and a weight of 3.1 ounces, it also features a Drop Point blade design with a plain edge and a flat grind made from AUS-8 (which is a Japanese, high carbon, stainless steel) with a Rockwell Hardness of 57-58 and your choice of a satin or a black, Titanium Nitride, finish. In addition, it features SOG’s S.A.T. assisted opening mechanism combined with a Piston Lock locking mechanism and a very ergonomic handle design made from Glass Reinforced Nylon. Last, it includes a reversible, tip-up only, steel pocket clip.
|(+) AUS-8 stainless steel blade||(-) Tip-up only pocket clip|
|(+) S.A.T. assisted opening mechanism|
|(+) Piston Lock locking mechanism|
Kershaw Injection 3.5
- SpeedSafe Assisted Opening makes for easy, safe and ambidextrous one-handed opening
- Reversible pocketclip makes storing the pocketknife a breeze; choose to change the tip position of the blade or even the side the knife carries; sits deep in the pocket for discreet carry
- Thumbstud perfectly placed for accessibility and ease of opening with just the push of a thumb
Not only does Kershaw offer one of the widest range of folding knives of any manufacturer on the market today, they are also well known for their quality and attention to detail and their Blur folding knife is no exception. Designed by famous custom knife maker Ken Onion, the Kershaw Ken Onion Blur features a closed length of 4.5 inches with a blade length of 3.4 inches and it weighs 3.9 oz. Also, it features a graceful, drop point, blade design with a recurved, partially serrated, cutting edge and a hollow grind made from 14C28N (which is Swedish, high carbon, stainless steel) with an unknown Rockwell Hardness and a matte black, Diamond Like Carbon (aka DLC) finish. In addition, it features Kershaw’s SpeedSafe assisted opening mechanism combined with a Liner Lock locking mechanism and a very ergonomic handle design made from 6061-T6 aircraft grade machined aluminum with Tac-Tec thermoformed rubber inserts that provide a very positive grip. Last, it includes a reversible, tip up or tip down, steel pocket clip.
|(+) Stainless steel blade||(-) Recurved edges are difficult to sharpen|
|(+) SpeedSafe assisted opening mechanism||(-) Serrated edges are difficult to sharpen|
|(+) Liner Lock locking mechanism|
- Outburst Assisted Opening
- G10 Bolster w/White Bone Handle
- Satin Blade Finish
The Columbia River Knife & Tool M4 folding knife was designed by custom knifemaker Kit Carson and features a closed length of 3.75 inches with a 3.25-inch blade and has a weight of 3.3 ounces. In addition, it also, it features a clip point blade design made from 8Cr13MoV (which is a Chinese, high carbon, Stainless Steel) with a Rockwell Hardness of 56-58 HRC combined with a plain edge, a hollow grind and, a satin finish. Plus, it also features a thumb stud and CRKT’s Outburst assisted opening mechanism combined with a Liner Lock locking mechanism and, it includes a very ergonomic handle design made from your choice of smooth bone handle scales with G10 bolsters, burl wood handle scales with stainless steel bolsters or, Sambar Stag handle scales with stainless steel bolsters.
|(+) Elegant design||(-) No pocket clip|
|(+) One hand opening and closing|
|(+) Choice of handle materials|
So, when choosing an assisted opening folding knife, the first step is to decide what the main purpose for your knife will be such as day-to-day utility cutting tasks or tactical use and then choose a blade design that meets your needs. Next, you should choose a knife made from a high quality stainless steel with an appropriate Rockwell Hardness because stainless steels will do a far better job of resisting corrosion due to constant exposure to perspiration and, the blade’s Rockwell Hardness will not only determine how tough the blade is, it will also determine how well it holds an edge. Then, you should choose a knife with a blade length that is appropriate for your intended purpose and which has a closed length that enables you to comfortably carry the knife in your preferred trouser pocket while also providing a comfortable and secure grip. Last, you should consider the type of locking mechanism the knife that you choose has since some types can be unlocked with a single hand while others require two hands. Thus, keeping these aspects of folding knife blade design in mind will help you immensely when sorting through all of the various designs on the market today while choosing one of the five designs listed above will save you a tremendous amount of time and effort.