Friday 24 March 2017

Survival Knives



What is this "Survival Knife" Craziness???













Sorry just have to say my bit about this crazy "Survival Knife"stuff.

Hopefully dispel some myths too.



Don't forget to read my video description too!






Monday 20 March 2017

Why I'm still loving my FKMD Combat Survival Knife!






Several years on and I don't regret buying this knife. Firstly, it's a knife that you're not afraid to really use (and often abuse). Make no mistakes it's tough as! When a knife comes from FKMD with the name of "Combat Survival" then I'm going to test it to the maximum with no holds barred! Forget all you worry worts about full tangs etc etc. If this knife was going to bust at the tang it would have after the first blow. Forget all you worry worts about the hypothetical "stress risers" on that saw back. It has not failed. Cast your minds to where I showed that the actual milling in the saw region leaves radii and no acute angles (which in the latter case might be a region of stress risers).



Love those serrations, still deadly sharp after countless batoning in this region and cutting of cords and ropes covered in crap. These are well designed serrations, no woosy cutting here!



The handle is super tough, albeit not the most comfortable but it works.




Lastly, the super tough FRN Molle scabbard with inbuilt diamond plate sharpener along with a very good wire cutter, is/has done it's "tour of duty" and is still going strong.



I'm still recommending it. If you don't mind a saw back (which BTW can easily cut hard plastics, wood (better on dead than green) make notches in no time flat.

I've been in the serious wilderness with ONLY this knife and never had my doubts over it failing me.

Hopefully more videos later this year!

Monday 13 March 2017




EXTREMA RATIO RAOII



The Story continues!





My Extrema Ratio RAOII gets a lot of use (and sometimes abuse!). here seen once again on the coast. Lots of salt water,  and salt spray. A good test for the materials in this knife.

I had the pin in 10 minutes ago bashing the daylights out of some birch i sawed up that was driftwood. About 7cm in diameter (it was dry). When batoning this knife you have to absolutely use the supplied pin otherwise the shock can unlock the pin. Nothing is going to happen but you might get a bit of a surprise! So use that pin if hitting the spine.

What's with all this stupid paint??? Well I needed to take the RAOII in a high vis area and when it was painted up fully (simple acrylic -non-permanent- don't worry ER no vandalism to this baby!). I had made it look, well kinda of "kids toy-like" LOL. In fact no one batted an eyelid when carried in the open. That's my "urban camo"!


Anyway it's been wearing off ever since, back to the Mil Spec matt black. Ok, so how is this knife holding up and what are my thoughts, a bit down the track? 







It's as tough as! Stays sharp and is dead easy to keep sharp. Holds that edge. NO problems with the mechanism, although I don't use it in muddy conditions as that roller lock system will just clog up with crap. Ok once it's clogged, if the knife is open, lock it out with the pin and then leave it as a "fixed blade" and clean it when u get back to civilization or sooner.




I think the biggest bonus to this folder is that it is unobtrusive when folded in or out of the pouch and this is good in high vis areas. Something no fixed blade unless concealed carry is going to offer. Plus when locked out with the pin, you do get a sturdy hefty knife that despite what it's critics say (most have no idea as they probably don't own one), it can take a real beating like a fixed blade and suffer no damage. This is amazing for a folder.
The downsides are that it is heavy and big, and this can't be helped if you want such a tough folder. The Extrema Ratio RAOII has it's place. It IS NOT easily field serviceable due to the numerous tools needed to open it up. The weakest link is still the small spring. If this breaks then the knife must def be carried as a fixed blade (not so much of a problem as it's doesn't destroy it's functionality).

Best lubricants to use:

High quality Mountain bike lubes that don't attract dirt or mud. be careful not to get it everywhere if u intend on cutting up food with the blade. Put it on the mechanism NOT the blade!





See my previous posts for what Loctite series to use to secure the locking screw after setting the blade tension. THIS IS VERY IMPORTANT AS THE WRONG LOCTITE WILL STOP YOU REMOVING THE SMALL SCREW IN THE FUTURE by possible burring of the screw slot or simply permanently anchoring the screw into the body. Know your Loctites!

Monday 6 March 2017



Advantages and Disadvantages of 3 common locking methods for folding knives




From L-R Liner Lock, Axis Lock and Lock back folders.




Currently there are 4*** general locking mechanisms employed on todays folding knives.

In no particular order:

1) The Liner Lock, whereby a section of one liner, is treated to produce a "spring mechanism" in order to engage with the rear of the knife tang.
Liner lock, showing precise engagement of the locking liner



2) The Axis or Roller lock Mechanism

The axis or roller locking method, whereby the blade is locked by the action of a "bar" under spring tension, engages with, or moves over the rear end of the knife tang. The blade is held in place as pressure upon the bar is not directed towards releasing the bar, hence only a relatively small weak spring is required to hold the bar from moving. Although any slight movement could cause a catastrophic closure!
Axis lock, note the partially visible spring attached to the "roller bar"

3) the Lock Back mechanism

 The traditional lock back mechanism. This mechanism has been around for some time and the locking is achieved when a notch in the tang of the blade engages with the opposing notch in a (usually) thick bar, which is also a spring and forming part of the knife body itself. The sides of the knife are in direct contact with the knife's liners (as is the case for non-locking folders for example, Swiss Army type folders etc
Traditional "lock back" note the notch (covered in grease, facing viewer) which forms part one of two of the locking mechanism

A traditional lock back folder, the blade is in direct contact across it's full surface with the knife liners.  

The blade on this axis locking folder is not in contact with the liners but only the surface area of the washers, in this case for this knife, a plastic and brass washer.

On this liner lock folder the blade is like that of the axis locking knife, only the blade is in contact with the washers, not the entire knife liners.


ADVANTAGES
The advantages of 1)

Quick to open one handed, relatively simple design.
Can be designed as a "flipper" for super fast operation.
Design lends itself for Rescue knife design, ie one handed operation.


The advantages of 2)

quick to open
left or right hand operation
Design lends itself for Rescue knife design, ie one handed operation.




The advantages of 3)

Left or right handed operation.
Large surface area of blade in contact with actual knife body
Few parts and therefore less affected by ingression of foreign bodies into mechanism.
Wearing of parts in direct contact with each other is slow.
Almost zero field maintenance or no user serviceable parts.
Spring tension is usually high and that means blade retention within the knife body is good.


DISADVANTAGES


Disadvantages of 1)

Because of the gap created by the spring liner foreign material can enter here, such as sand, mud or sticks etc and render the mechanism inoperable unless cleaned.

Knife is only "handed" ie for a right hand closure, the liner that moves must be on the left hand side as viewed when looking at the open knife tip uppermost. The a left hand closure, the spring liner must be on the right hand side as viewed similarly.

The rear of the knife, ie tang is only in contact with washers (plastic or metal or a combination of both). This means the knife body plays no part in stabilizing any lateral forces exhibited upon the blade. 

Once washer/s wear sufficiently, then the knife will require servicing. This is an almost impossible task to perform in the field as it requires small screw drivers or torx head drivers or the like to be carried in order to strip the knife and replace the washers.

Indent setting plays large role in blade retention in the closed position- depends on the manufacturer.

Washer tension must be set right in order for proper operation.



Disadvantages of 2)

Locking mechanism's weakest link is the small spring. If this fails (it will have a limited lifetime of operation), then the knife can not be closed or locked safely.

The axis system,  is open to ingression of foreign matter rendering the opening and or closing to be impossible until the material is cleared. 

This knife design sports the greatest number of small parts. The more parts the more things there are to fail.

Sudden Vibration forces greater than the holding force of the roller spring can actuate the roller and cause disengagement.

Depending on the strength of the roller spring, the blade can come out of it's enclosure if subject to a downward force (such as falling tumbling etc).

Spring tension is usually weak and blade retention within (closed position) is just OK.

Washers will wear out and require service, small parts can be lost in the field. Field servicing not advised.

Washer tension must be set right in order for proper operation.



Disadvantages of 3)

Due to a larger surface area of blade tang in contact with steel liners, there is more friction generated and a requirement for adequate lubrication is a must for smooth long life time operation. Failure to do so can wear parts which are not user serviceable or possibly serviceable by the manufacturer.


*If the spring back is not sufficiently strong then pressure against the locking mechanism opposing the lock can cause the lock to fail or if the notches are not deep enough (only seen on poorly designed lock backs).

2 hands are generally required to open the knife. Although it is possible for one handed opening.






* any poorly designed versions of 1) or 2) can also suffer unexpected closure.


***A quick note on Frame Locking knives.


I don't mention Frame Locks as I think this is a poor design compared to the above knife designs. I'll explain in another blog why but briefly, poor lock up first time, as it is vey difficult for manufactures to get the correct springiness within the same part of the knife which serves as part of the body of the knife. Also if manufacturers use materials for scales which do not possess good properties for springs and other smaller parts are required.   

I'll also say why the marketing guys have you believing otherwise.


Saturday 4 March 2017

Now my Extrema Ratio Fulcrum S (modified) satisfies

my criteria for a "Survival-type Knife"*
Notice the lack of the upper guard?


*ie easily field maintained; rugged construction; comfortable; few parts; corrosion resistant; sturdy non-rotting safe and multi-mounting carry system; straight blade and strong tip and no hot spots during vigorous usage.

You know with all those knife models out there from commercial knife manufacturers, I've still not been able to find the "ultimate knife" for my uses. AND that's because there isn't an "Ultimate Knife" for every (realistic) task you can think of!

However, sometimes some knives have a lot nice features but lack in other areas of which one can not help but think, "what was the manufacturer thinking when they came up with this design"?

To that end I took my Extrema Ratio  Fulcrum S and modified it. In fact, Extrema Ratio did indeed have this (very similar) model and they called it the K9. I never owned a K9 but now I do, well sort of! BTW the K9 has long since been discontinued and I wonder if it had had some worthy field testing done and proper publicity then it still might be manufactured today.

I have to say I could only find one very very basic written review (in English) about the Extrema Ratio K9 and it is here.
You will see that the the main blade geometry is exactly the same as the Fulcrum  without the upper guard. If you have now read this short article then you will also see the Author's opinion on double guards functionality in real situations. I'd have to agree with them on this point. Double guards unless ginormous are really a relic of the past for supposed tactical military knives.

NOW what did I do? I removed my handle of my Fulcrum S, put the blade into the vice, took a "Dremel style" hobby drill with a carborundum wheel and using water to cool the job, I removed the upper guard, to no less than the existing upper gimping. Now I can really get all over this knife without the upper guard getting in the way. 

I re-ground the blade edges to a slightly less steep angle to get a better "biting edge". Plus this makes it "cut" much better and isn't that what a knife is supposed to do, cut? I tested this out by deboning lots of slimy chicken meat. Unless a knife is very good at cutting you are going to go nowhere fast trying to debone chicken, as unlike red meat on the bone, chicken tends

 to move around a lot, so there is little resistance against a knife edge and therefore you must have a very good cutting edge. No problems with this slight modification. In fact the grind is now more like the grind that came already on my Extrema Ratio ONTOS (which is BTW marketed as a "survival Knife"- and one statement i can't argue with based on loads of solid field testing across both hemispheres).

So what about two guards???

YES I did indeed advocate uses for this upper guard other than some sort of crazily small protection issues but after long thought ( I don't take back what I had previously said, as many still love the twin guards thing- I myself own and love my Spec Plus- but the guards are not aggressive) I think now the knife is very very nice and I'll list the reasons here:

1) Extremely robust knife construction with only one part (two if you count the nut and bolt as separate items)

2) Handle anchoring bolt can be removed with a flat bladed instrument or an "Allen key"

3) If allen bolt was to be lost then the handle can still be anchored with simple cordage through the lanyard hole.

4) Other than the small section of serrations** the cutting edges are all straight. This means the knife could not be easier to sharpen in the field, no funky curves and that makes it simple to sharpen.

5) The weight distribution of this knife makes it easy to chop into coconuts (a pretty tough order for any knife other than a Parang and or a machete style knife. Why do I mention this? Well, I've been extensively trekking in regions where the only drinking water readily available and uncontaminated is sitting above your head, in coconuts. We used them for drinking and cooking and if you can't access this stuff then you are going to be digging up your water or something else. To that end you need a damn strong knife to do this. So I reckon this knife passed that test.

6) Western style Tanto tip. Easy to sharpen and easy to penetrate. Can be used as a chisel to make things. It's very strong.

7) Blade not hardened above HRC58. This also makes it resist the effects of corrosion better and of course not so difficult to sharpen with natural stones found in the field.

8) The blade contains some shallow serrations which, to tell you a little know secrete of those in the know, outside of slicing through ropes like no tomorrow (if well designed (ie shallow and deep concave cuts), serrations can be used to very very effectively produce "feathers" for fire tinder making, much better than any straight section of blade.

9) Did I say lever??? There are no holes situated close to the knife's fulcrum (no pun intended).

10) The handle is good even in very cold weather as there is little exposed metal surfaces that a bare hand would encounter.


To this end, I will taking this modified knife as my only knife into the wilds once again and try and showcase what I think the so-called "Survival knife" must encompass.







* for my uses