The Edge Observer

Extrema Ratio

Extrema Ratio Fulcrum 2

Published: July 15th, 2012 by The Edge Observer 6

The Extrema Ratio Fulcrum 2 is a heavy duty folder that was developed along side an Italian anti-terrorism unit. It was designed to meet specifications that extended its use as a cutting and fighting knife to include the ability to pry. The prying functionality comes from its thick .236″ (6 mm) blade. At a modest length of 3.74″ it is very stout, providing the necessary lateral strength for abusive tasks. The Fulcrum comes in two versions : what Extrema classifies as a drop point and a tanto. The profiles could also be considered having clipped points due to the sharp angle ground from the spine toward the tip. Both versions have a flat primary bevel and steep swedge. The drop point comes in a plain edge while the tanto a partially serrated one.

Although not a graceful slicer, the Fulcrum 2 is still competent for general utility tasks. Where the geometry really excels is in penetrating cuts. The sum of the grinds on both versions terminate at a spike like tip that can be forced through materials easily. The blade has ambidextrous thumb-studs for deployment and a steep, jimped thumb ramp for added control. All versions have a mil-spec black oxide coating.

The tang travels on a fat pivot and against teflon washers. When opened, a heavy back-lock holds the blade firm and without play. This component is also .236″ thick and hinges on a hidden pin. The lock spring is ridged and while it provides excellent security, makes for a resistant deployment. It also snaps the blade shut at about 30º. As a side note it is quite resonant, announcing itself without subtlety.

To ensure the knife stays open in use, there is an additional safety lock that prevents the back lock from disengaging. Extrema mentions that the safety can also be used to keep the knife closed in case it is taken ‘without authorization” by a person who is unfamiliar with the mechanism. This purpose may be easily foiled however as the words “lock” and “unlock” are clearly written on the scales. Perhaps not though, as words are backward from my perspective as you push on the side labelled ‘unlock’ to lock the knife and vice versa. Quirks aside this simple safety works well and is one of the more solid mechanisms I’ve tried. Because of the intended hard use of the knife it is also an appropriate feature.

The butt / back-spacer carries on the same thickness as the blade and back lock. This forms a pointed pommel that can be used as an impact tool or weapon. The utility is greatly enhanced by the thumb ramp as it creates a finger groove when the knife is closed. This part also houses the lock spring, a large lanyard hole and is engraved with a unique serial number.

The thick spine of the knife is held between matte black anodized, aluminum scales. The general shape of the handle is boxy and the surface smooth. To add comfort, all angles are chamfered. There is a finger groove to help with retention that also flares into a front guard. As with the majority of Extrema’s handles, there is a relief milled for the first finger that also allows for easy access to the thumb studs. Although angular in appearance, the grip is comfortable and secure. There is a large tip up ambidextrous pocket clip for carry. The knife has also been designed to easily fit into a pistol magazine pocket.

The handle on the Fulcrum is well thought out and provides good support for the blade. It also has a low part count and simple components that will allow for easy maintenance. The entire assembly is held together with three fasteners, including the pivot (excluding the clip bolts) Extrema includes the two allen keys necessary for adjustments. There are also an extra set of bolts that are inserted in the holes opposite the clip.

Over all the Fulcrum 2 is a stand out folder. Although not a huge knife it is a competent tool with its heavy build and prying capabilities. Co-designed by and geared toward military and law enforcement, the knife would also make a great collectors piece as it is truly one of a kind.

I really only have one criticism of this knife : The giant, garish “Extrema Ratio” and “58HRC Stainless Cobalt Steel” plastered on the primary bevel. I really wish manufacturers would let the blade breathe instead of adding gaudy details and tactless logos where they are not needed. Some might also criticize the weight of 7.05 OZ ( 200 g ) but unlike many folders in this weight category, you are getting much more “pound for pound”.

The Fulcrum 2 Tanto was supplied by JB Tactical where both versions are available.

Pros

Great build quality
Ability to pry
Good fit and finish

Cons

Ugly blade text is an eyesore

Specs

Length Open 8.66″ (220 mm)
Length Closed 4.92″ (125 mm)
Weight 7.05 Oz (200 g)

Blade

Blade Length 3.74″ (95 mm)
Blade Thickness .236″ (6 mm)
Blade Steel N690 (58HRC)
Flat grind, plain edge in drop point and combo edge in tanto
Finish Mil-spec black oxide

Handle

SAG Anticordal Aluminum Matte black anodized
Tip up ambidextrous clip

Lock

Back Lock
Safety, locks open and closed

Made in Italy

Extrema Ratio BF M1A1

Published: April 29th, 2012 by The Edge Observer 9

The BF M1A1 (basic folder series) is Extrema Ratio’s first foray into small form factor pocket tools. The size and features are quite comparable to classic Wegner or Victorinox Swiss Army Knives but it is distinctly Extrema Ratio in its over-all design and material choices.

The knife features three main tools: a drop point blade, marlin spike and a multi-tool that has a bottle opener, can opener and flat head screwdriver. The blade and multi-tool are held open via independent liner locks and the marlin spike by a slip joint.

The handle has an open build, screw together, flow through pillar construction for easy maintenance. The multi-tool rests in-between two stainless liners (left and centre) that also comprise the liner locks. The blade is seated between one stainless liner and the outer Anticordal aluminum scale. The marlin spike is held against a large standoff on one side and the scale on the other. The blade and multi-tool travel against teflon washers while the Marlin Spike does not have any washers.

As to be expected with Extrema, the liner locks are without play. The slip-joint holds the marlin spike firmly closed but there is some side to side play present.

Both liner locks have jimping on the outer edge for easy release. The leafs are also offset in order to allow equal access to both, without having to dig around to find the one you want to disengage. This feature is fairly well executed as it makes the locks easy to access without creating a noticeable hot spot while using the knife.

The blade has a very similar profile to Extrema’s other BF drop point offerings. This knife is the only one in the line with a natural finish however. All other BF’s have a mil-spec, black oxide finish. A full flat grind will make the blade good for everyday utility tasks. The .118″ (3mm) blade stock should allow it to take on any jobs you would typically have a small knife perform. Made from Bohler N690co and hardened to 58 HRc it is very corrosion resistant and tough, yet easy to maintain. There is a right handed thumb stud for deployment. Although the thumb stud sits against the frame, it is high enough that it can be easily used.

The multi-tool is a little harder to get a hold of. Due to the liner lock design, there is only a very small amount of the bottle opener poking out. If you don’t have a bit of thumb nail you might find yourself opening the blade, then the multi-tool and finally closing the blade to get it out. That, or pushing it out through the back. Either way, a bit more length on the tool would help considerably. This aside, it is effective at opening cans, bottles and as a small flat head screwdriver. I would avoid any prying with it though, as the shape forms a narrow neck between the openers at the tang. Lastly, the marlin spike is a great feature for those who often deal with a variety of knots and at 1 3/4″ long and about 1/4″ in diameter, is excellent for most relevant tasks.

The M1A1 has a bridge style pocket clip. It has quite a bit of tension and will appeal to users who like strong clips. Because of the shape it also rides very low in the pocket, completely concealing the knife’s handle. The satin finish nicely ties in all of the other stainless elements. The clip can be reversed for left hand carry, but everything else on the knife is designed for right handed users. Because of this, the extra machining doesn’t really seem necessary.

The sum of the parts produce fair ergonomics. Although the M1A1 is smallish, the handle’s width fills the hand well. With the exception of deploying the multi-tool element, everything feels to be in the right place and the knife is comfortable to carry and use.
The over all fit and finish is slightly above average compared to most manufacturers, but below average for Extrema Ratio. There is some cosmetic finishing that could be improved. The forefinger indents have some machining still visible and the plunge line on the blade could be smoother. The most noticeable part is the multi-tool component, which has some wonky machining and sharpening on the can opener. As a utility knife this may not bother some, myself included, but it is certainly of note when compared to Extrema’s other BF offerings. That said, you still get a fair bit of knife for the price (by Extrema’s standards) and outside of these cosmetic issues it is mechanically sound.

All-in the BF M1A1 is an apt competitor for this style of pocket tool. It offers a very different aesthetic to its Wegner and Victorinox competitors and a much more robust build quality. Similarly it may not appeal to the traditional Swiss Army Knife crowd as its design has a much more aggressive appearance. It also weighs in a little heavier than your average S.A.K. at 4.4 Oz or 125 Grams.

This knife will surely appeal to Extrema Ratio design fans looking to carry a slightly more politically correct, versatile and less expensive model from the company. It will also fill the roll of a reliable pocket tool for everyday tasks in a recreational or professional environment. The strong clip, corrosion resistant materials and marlin spike would be an excellent combination for people who spend a lot of time on the water.

Pros

Good build quality
Attractive design
Useful tools

Cons

Cosmetic finishing issues
Can/bottle opener is a pain to open

Specs

Length closed: 3.94″ (100 mm) Length open: 6.69″ (170 mm)
Weight: 4.4 Oz (125 g)

Tools

Small Flat head screwdriver
Bottle Opener
Can Opener
Marlin Spike

Blade:

Böhler N690Co
HRc 58 Blade length: 2.75″ (70 mm) Blade thickness: .118″ (3 mm)
Handle:

Anticorodal Aluminum
Ambidextrous, Tip up, Low riding Bridge style clip
Locking system:

Liner lock (Blade and Multi-tool)
Slip Joint for the Marlin Spike

Made in Italy 

Extrema Ratio BF3 Dark Talon

Published: January 5th, 2012 by The Edge Observer 7

The BF-3 by Extrema Ratio is a unique tactical folder. It’s long slender design is both graceful yet menacing. The knife is fittingly named after its blade shape : The Dark Talon.

The Dark Talon belongs to Extrema’s basic folder (BF) series. This line of knives is primarily designed with everyday, concealed carry and back-up in mind. Although quite long for an EDC folder, it fits comfortably in most pockets. The narrow design causes the knife to have little presence and the deep riding pocket clip keeps the lengthy 270mm (5.9″) handle out of sight.

The N690co blade on the Dark Talon commands respect. Using a 3mm blade stock, spanning a length of 120 mm (4.724″) and with a maximum width of of only 24mm (.95″), the blade is extremely pointed and razor like. With a long, downward sloping spine the near to straight, fully flat ground edge is fed into thrust cuts with ease. The blade geometry makes for an extremely mean appearance that will perform its intended tasks well. On the contrary the narrow, thin blade will also limit its application to jobs with low lateral stresses.

The BF-3 uses thumb studs for deployment. In keeping with the slender profile and lack of real-estate on the blade, the thumb studs are butted against the handle. This makes for a fairly slow deployment, and for a tactical style folder, is never really a good thing. With some practice and a fairly heavy flick of the wrist, it can be overcome but this design detail may need some work.

The blade is held firmly in place with a liner lock. Extrema’s lock design features a very small leaf that sits flush with the anticordal aluminum frame. The shape and position keeps it tucked out of the way, preventing accidental closing. As a result, it may also make it a little trickier to disengage with one hand for some. Personally I prefer this design on a tactical folder as it allows for much safer use. As to be expected from Extrema, there is zero blade play in any direction due to sound engineering and excellent tolerances.

The handle’s lengthy sloping shape is comfortable. A slight rise on the inside of the handle where the liner’s locking leaf is housed helps to prevent forward slipping. The butt of the knife is flat allowing you to put your thumb across it, providing some extra purchase in a reverse grip. All-in the handle is reasonably ergonomic but it feels a bit slippery because of its smooth, untextured handle scales.

The blade is finished with MIL-C-13954. This is a black oxide coating that provides a dull matte black finish. Although it looks great and is up to NATO military specifications, MIL-C-13954 is not a very durable coating and will mar quite easily with everyday use. The handle is also matte black with a hard-anodized finish. In typical Extrema fashion, the liners and all hardware are matching, leaving only the knife’s model info and sharpened edge otherwise.

The Dark Talon is a very slick looking knife. Extrema Ratio’s manufacturing, great materials and stand out design will make this very attractive to collectors. The geometry will limit the knifes utility in real world use but will definitely perform the intended tasks with flying colors. At total length of 270mm (10.62″) and 4.4 Oz the knife should also be a great option for users looking for an easy to carry tactical folder with exceptional reach. My only real criticism here would be the deployment which could possibly be remedied with a slight handle cut-out or wider tang to allow the thumb studs to be positioned farther away from the scales.

Pros

Distinct design
Great reach
Excellent, detailing, fit and finish

Cons

Thumb studs are against the frame
Limited application

Specs :

Total Dimensions and weight :

length open 10.62 in (270 mm) 
length closed 5.9 in (150 mm)
weight 4.4 oz (125 g)

Blade :

blade length 4.72 in. (120 mm)
 blade steel Bohler N690co 58HRc
 blade thickness 1/8 in. (3 mm) 
cutting edge 4.72 in. (120 mm) 
MIl-C-13954 black oxide finish

Lock :

Liner Lock

Handle :

Anticordal Aluminum
Stainless Liner for lock side
Ambidextrous Tip up Low Riding clip

Made in Italy

Extrema Ratio R.A.O.

Published: July 26th, 2011 by The Edge Observer 2

In 2006 The Extrema Ratio R.A.O. was commissioned by the 185° Rgt. Ricognizione ed Acquisizione Obiettivi” (Target Acquisition Regiment), airborne “FOLGORE” (“Lightning”). This elite special forces unit conducts long-range recon for the purpose of acquiring targets (for air-strikes, artillery and warships) as well as providing battle damage assessment. They operate in all theatres of war and are the only one of its kind in the Italian Military. Their Motto is “Videre Nec Videri”, Latin for “See Without Being Seen”. The 185º will often carry out missions from 8-10 days without supplies in enemy controlled territory. This dangerous job requires them to operate in small self sufficient groups and demands a compact versatile field knife: the Extrema Ratio R.A.O.

Compact is definitely a matter of context. The R.A.O. is a very large for a folder.
With a .24″ (6 mm) thickness, the massive N690 blade measures at almost 4.75 inches long and 1.75 inches at its widest. The blade spine has 1.6″ inches of aggressive jimping followed by a wide swedge and lastly a sharpened upper edge. The primary edge is straight with a tanto like tip that meets the swedge edge forming a triangular point. It roughly resembles two tanto blades back to back and can be used for chopping, prying, digging and cutting. The hefty blade rotates on a 6mm pivot and against two nylon bushings. The 185º Reg. logo and motto is laser engraved on one side while Extrema’s is on the other.

The R.A.O. Has a large clip-less Anticordal aluminum handle (Anticordal is a brand name of harden-able silicon-aluminum.) likely designed for use with gloved hands. This houses the main lock, a spring-backed .24″ (6 mm) pin that fits into a deep tapered slot in the tang when open. There is also a shallow slot on the opposite side of the tang that holds the blade in the handle when closed. The front guard (quillon) has a threaded hole that can house a screw-in safety pin, protecting the blade from accidentally closing when under stress while chopping or striking. The pin is connected to an elastic lanyard that also serves to wrap around the hand while using the knife. Slight scallops in the rear add some extra ergonomics but the outward swept rear guard is responsible for keeping the knife firm in the hand. A large steel backspaced extends past the butt forming a substantial glass-breaker or “persuader”. To criticize, the elastic lanyard is a bit of a pain when threading in the safety pin because it winds at the same time. A rotating joint on the pin would improve its function greatly. The handle also feels a little flat for its size but overall gives you a very secure grip that, combined with the safety pin, provides confidence while under heavy use.

The knife comes with a M.O.L.L.E. compatible nylon carrying system. This is robustly constructed and can accommodate the knife while open or closed. When folded, a shaped, open bottom pocket firmly holds the knife and is covered with a large clipped flap. When open a secondary rubberized sheath is available on the back side of the pocket. The R.A.O. is held in this sheath via a double snapped strap This also has an open bottom as not to hold liquid and dirt. The carrying case has a third feature that holds a decent diamond pad sharpener laminated on an anodized aluminum backing. The sharpener has a small paracord lanyard attached.

Over-all the R.A.O. is a capable folding mil-spec field knife. It’s hard use design, additionally safety feature and adaptive carry system combine to create a useful, reliable and practical cutting tool.

Pros :

Heavy Duty
Excellent M.O.L.L.E. Compatible Carry system
Safe Lock
Mil-Spec/Military with 6 years use

Cons :

Elastic Lanyard/Pin winds when used

Specs :

Total Dimensions and weight

length open 10.25 in (260 mm)
length closed 4 3/4 in (121 mm)
weight 12 oz. (17.8 Oz with sheath) 340 g (505 g with sheath)

Blade

blade length 4.72 in (141 mm)
blade steel N690co
blade thickness .24 in (6 mm)
cutting edge (including the sharpened upper tip) 5.55″ in (141mm)

Lock

Spring loaded Pin in tang
Screw in safety pin

Handle

SAG Anticordal Aluminum

Made in Italy

Understanding Extrema Ratio Folder Classes

Published: June 28th, 2011 by The Edge Observer 1

Samples of folders classes : Heaviest (RAO) Heavy (MPC, Fulcrum 2 D), MF (MF1, MF0) and BF (BF3, BF2 CT)

Extrema Ratio folding knives are separated into four main categories. These are the BF or “Basic/Light Folders” MF or “Medium Folders”, “Heavy Folders” and “Heaviest” (there is currently only one in the Heaviest category, the RAO).

When you first begin looking to purchase ER knives it would be intuitive that the difference between classes would be an increase in features and size (something like Benchmade or Sniper Bladework’s full size vs mini) but this is not the case. Some knives in the BF series are actually larger than MF and Heavy series knives. Another example would be that all the MF knives feature a tungsten-carbide glass breaker while the BF, Heavy and RAO folders do not.

This can be a bit confusing for a first time buyer or collector but it is clear once you understand a couple of distinctions. Extrema Ratio knives are not classified by features or size but by their intended use, lighter civilian use vs hard professional use.

These distinctions manifest themselves in a couple of ways. Firstly by lock types: all BF and MF knives feature a liner lock with a safety except for the BF3 which does not have a secondary safety. Heavy series knives use a back-lock with a safety while the RAO uses an axis like lock with a screw in safety pin (both Heavy folder lock styles are known for mechanical dependability). Secondly BF and MF knives feature a low ride pocket clip for concealment; Heavy folders and the RAO are designed for professional use where concealment isn’t necessary. Lastly the classes are differentiated by material usage. Heavy folders and the RAO have 6mm blade stock, MF’s 4mm and the BF series 3mm.

Extrema Ratio BF2-CT and the Fulcrum 2D.

Knowing these points shed quite a bit of light on the decision making process. If you are looking for a slim knife for lighter cutting duties or self defense then the BF is for you. For something more robust yet still concealable with a tungsten glass breaker, then go for the MF and if you are looking for a real hard use knife and aren’t concerned with weight or political correctness then the heavy or heaviest categories would be where you should look. Your preferred reach can likely be found in all categories.

It is good to note that all of the Extrema Ratio knives, despite the class/category are manufactured from MIL-C-13924 Carbon Coated Bohler N690 steel for the blades and liners and use SAG’s Anticortal Aluminum for the handles. The fit and finish on the BF series is just as good as on the Heavy series so no matter what you choose you will be getting the full Extrema Ratio quality that you would come to expect at the premium that they ask.

Lastly you should know that there are many Extrema Ratio knockoffs. It is recommended that you purchase from an official Extrema Ratio Dealer or other credible seller to ensure your money is well spent.