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| Knife Review: Extrema Ratio TASK J |
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Posted by: subwoofer - 02-27-2018, 05:36 AM - Forum: Knife and Blade Reviews
- Replies (2)
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![[Image: 00-Extrema-R-Task-J-feature-P1260639.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/00-Extrema-R-Task-J-feature-P1260639.jpg)
Based on the original TASK tactical knife designed by Thilo Schiller, this version of the TASK, the TASK J has been developed as a collaboration with the Jagdkommando Unit, the Austrian Army special forces. Their requirements were for a heavier duty version of the original TASK which could survive more extreme use.
![[Image: 00-Extrema-R-Task-J-feature-P1260559.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/00-Extrema-R-Task-J-feature-P1260559.jpg)
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Author's Statement for Transparency and Disclosure
The test sample/s featured in this article have been provided for technical testing and review by the manufacturer. Test samples are retained by the reviewer following publication of the completed review for the purposes of long term testing and product comparisons.
All output figures and test results published in this review are the sole work of the reviewer, and are carried out independently and without bias. Test results are reported as found, with no embellishments or alteration. Though best endeavours are made to maintain the accuracy of test equipment, the accuracy of these results is not guaranteed and is subject to the test equipment functioning correctly.
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The Blade and Handle Geometry:
Most knife specifications have a basic description of the blade geometry, but in this section I will be taking a more detailed look at geometry and balance.
![[Image: 48-Extrema-R-Task-J-grind-P1270933.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/48-Extrema-R-Task-J-grind-P1270933.jpg)
Using a set of gauges and precision measuring equipment including a Vernier protractor, callipers, fixed radius gauges and the unique Arc Master adjustable radius gauge (the one that looks like a crossbow).
![[Image: Knife-measuring-P1180483.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/09/Knife-measuring-P1180483.jpg)
These measurements have been tabulated and are presented along with a few reference blades (8" Chef's Knife, 5.5" Santoku and the popular Fällkniven F1).
Key aspects such as the primary bevel angle, grind type, blade depth, blade thickness, length, weight are detailed, along with balance information.
![[Image: 49-Extrema-R-Task-J-bevel-P1270938.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/49-Extrema-R-Task-J-bevel-P1270938.jpg)
The 'Balance relative to the front of the handle' tells you if the knife will feel front heavy, or if the weight is in your hand (a positive value means the weight is forward of the front of the handle). The 'Balance relative to the centre of the handle' indicates how close to a 'neutral balance' the knife has in the hand.
![[Image: 47-Extrema-R-Task-J-balance-P1270922.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/47-Extrema-R-Task-J-balance-P1270922.jpg)
In the case of full convex grinds the approximate centre of the grind is used for the primary bevel angle estimate.
![[Image: More-Marker-V2-100h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-100h.png)
(Wherever you see the 'Read MORE' marker, it indicates that the Extended Version of the review has additional content at that point. Viewing the extended version helps support further reviews, but please ensure you return to this Forum for comments and discussion.)
The blade is made from ACCIAIO BöHLER N690 (58HRC) steel.
New for 2018! BESS Certified sharpness testing:
The BESS 'C' scale of sharpness, developed by Mike Brubacher (Brubacher Edge Sharpness Scale) will now become part of Tactical Reviews' knife testing process. Initially this will be used to verify the sharpness of the factory edge and allow the knife to be brought to a minimum standard sharpness before testing a blade's cutting performance.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
The TASK J's factory edge has an average BESS 'C' sharpness of 533. Though this officially comes in as a 'dull' edge, it will just slice 80gsm paper. Because there are some areas at a BESS 'C' score of 407, that allows for a borderline working edge, which is the only reason it is possible to slice 80gsm paper with this factory edge.
![[Image: 50-Extrema-R-Task-J-BESS-1-P1010185.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/50-Extrema-R-Task-J-BESS-1-P1010185.jpg)
Explained by the Maker:
The reasons for certain design choices may not be clear when simply looking at an object, so this section is intended to give an insight into the thinking behind a design by speaking to the designer themselves.
Unfortunately I can’t always get time with the designer so will use this section to include relevant information about the knife and its designer.
Direct quote from Extrema Ratio's website.
"This tactical knife has been developed together with material experts of Jagdkommando Unit, the Austrian Army special force. It is a multi purpose tactical knife with double guards to avoid accidentally slipping of the hand on the blade. It comes with standard desert side sheath with automatic retention mechanism and protective slap. A fireball flint and striker is placed inside the sheath."
A few more details:
A well made cardboard box is used for the TASK J.
![[Image: 01-Extrema-R-Task-J-box-P1260402.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/01-Extrema-R-Task-J-box-P1260402.jpg)
The full package is wrapped in a plastic bag, and fills the substantial box.
![[Image: 02-Extrema-R-Task-J-box-open-P1260418.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/02-Extrema-R-Task-J-box-open-P1260418.jpg)
Along with the bagged knife are two leaflets and a quality control card.
![[Image: 03-Extrema-R-Task-J-box-contents-P1260423.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/03-Extrema-R-Task-J-box-contents-P1260423.jpg)
Slipping the TASK J out of the bag; the leg strap is kept neatly in place with a rubber band.
![[Image: 04-Extrema-R-Task-J-wrapped-P1260428.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/04-Extrema-R-Task-J-wrapped-P1260428.jpg)
Taking a moment here to mention that Extrema Ratio have packed the design of the sheath with so much detail, this needs to be appreciated, so we'll be covering this before moving onto the knife.
Being a full size knife, there is a removable leg strap to allow you to really keep it under control in vigorous situations.
![[Image: 05-Extrema-R-Task-J-leg-strap-P1260433.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/05-Extrema-R-Task-J-leg-strap-P1260433.jpg)
The leg strap has a double elasticated section so you can fit is snugly without then finding it cuts in uncomfortably.
![[Image: 06-Extrema-R-Task-J-leg-elastic-P1260437.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/06-Extrema-R-Task-J-leg-elastic-P1260437.jpg)
Both ends of the leg strap are adjustable in length using velcro. There is an elastic cover to slide over the end of the strap end to prevent it from being pulled away during use.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
Onto the main sheath. The most obvious atypical feature is the full knife handle cover; as shown here, the knife itself is almost fully concealed. This flap is a critical feature to help prevent a knife fitted to a pack becoming a 'hang up' hazard. With the flap over the knife handle it is far less likely to catch on something.
![[Image: 10-Extrema-R-Task-J-sheath-P1260456.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/10-Extrema-R-Task-J-sheath-P1260456.jpg)
Not relying on a fabric to keep the blade from cutting through the sheath, there is a full plastic sheath liner. This is the bottom of the sheath with the special fixing (visible on the front of the sheath) and the black plastic liner plug that closes off the end of the liner, but leaves gaps for drainage.
![[Image: 11-Extrema-R-Task-J-sheath-insert-P1260460.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/11-Extrema-R-Task-J-sheath-insert-P1260460.jpg)
A high quality plastic snap buckle holds the knife cover flap in place.
![[Image: 12-Extrema-R-Task-J-sheath-buckle-P1260465.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/12-Extrema-R-Task-J-sheath-buckle-P1260465.jpg)
Rolling the sheath over and there is a full length MOLLE fixing strap.
![[Image: 13-Extrema-R-Task-J-sheath-molle-P1260470.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/13-Extrema-R-Task-J-sheath-molle-P1260470.jpg)
The top of that MOLLE strap is what holds the removable knife cover flap in place.
![[Image: 14-Extrema-R-Task-J-sheath-flap-P1260474.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/14-Extrema-R-Task-J-sheath-flap-P1260474.jpg)
Here the knife cover flap has been folded under the rest of the sheath. Note the thin black cord running down the side of the sheath.
![[Image: 15-Extrema-R-Task-J-sheath-flap-folded-P1260479.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/15-Extrema-R-Task-J-sheath-flap-folded-P1260479.jpg)
That cord runs all the way down and is held by the MOLLE strap press stud.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
The knife retention strap is also adjustable / removable, with velcro holding it in place.
![[Image: 22-Extrema-R-Task-J-sheath-retention-P1260524.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/22-Extrema-R-Task-J-sheath-retention-P1260524.jpg)
The primary knife retention is not the strap, but is a plastic tab that is part of the sheath liner.
![[Image: 23-Extrema-R-Task-J-sheath-retention-P1260529.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/23-Extrema-R-Task-J-sheath-retention-P1260529.jpg)
You can see how the side of the handle hits that plastic tab as you insert the knife into the sheath.
![[Image: 43-Extrema-R-Task-J-sheath-lock-P1260624.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/43-Extrema-R-Task-J-sheath-lock-P1260624.jpg)
Push a little more firmly, and the knife clicks into place. It is now held in the sheath by this plastic tab, requiring a firm pull to free it.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
Having covered its feature packed sheath system, here is the TASK J.
![[Image: 24-Extrema-R-Task-J-with-sheath-P1260533.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/24-Extrema-R-Task-J-with-sheath-P1260533.jpg)
Though similar to the TASK in that it has a double-edged, modified wharncliffe blade, the primary bevel is quite different, as well as the blade having a bayonet grind.
![[Image: 27-Extrema-R-Task-J-angle-P1260572.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/27-Extrema-R-Task-J-angle-P1260572.jpg)
The blade is symmetrically ground.
![[Image: 28-Extrema-R-Task-J-angle-reverse-P1260574.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/28-Extrema-R-Task-J-angle-reverse-P1260574.jpg)
Extrema Ratio's distinctive Forprene handle is used, in this case the desert colour.
![[Image: 29-Extrema-R-Task-J-rear-angle-P1260594.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/29-Extrema-R-Task-J-rear-angle-P1260594.jpg)
Used on several models, this recognisable handle is particularly effective. The grip design provides a secure dual finger groove and the Forprene material cushions the user from the shock of heavy blows.
![[Image: 30-Extrema-R-Task-J-handle-P1260586.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/30-Extrema-R-Task-J-handle-P1260586.jpg)
Another clear design feature intended for extreme use, is the double guard which provides the greatest protection against the hand slipping forward onto the blade.
![[Image: 31-Extrema-R-Task-J-model-P1260577.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/31-Extrema-R-Task-J-model-P1260577.jpg)
A well radiused plunge line keeps maximum strength at the transition from cutting edge to ricasso. Note the lack of a choil which in this case removes the chance of a hang-up if the blade has made a full depth cut.
![[Image: 32-Extrema-R-Task-J-plunge-P1260565.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/32-Extrema-R-Task-J-plunge-P1260565.jpg)
There is a single bolt to keep the handle in place.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
To properly show the proportions of the TASK J, this side shot minimises perspective distortions.
![[Image: 38-Extrema-R-Task-J-full-side-P1260602.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/38-Extrema-R-Task-J-full-side-P1260602.jpg)
What it is like to use?
Extrema Ratio's TASK J is not what I would normally think of as your 'every day' knife. It is a specifically heavy duty knife, for conditions where you need that absolute assurance the blade is as strong as it could be and will take anything you throw at it.
The superb attention to detail in the sheath design only reinforces how the whole package is intended to work in conditions most of us will thankfully never have to endure. With comprehensive carry options you can pack this knife in all sorts of ways and know it will still be there with you through the worst.
What the TASK J does that is different to most of the other knives capable of demolition/extraction work, is to maintain the more refined feel of a general purpose knife instead of just seeming like a large slab of steel - an important distinction.
Taking the TASK J in hand, and it is a full size knife, having a blade just over 6" long. The ultra modern looking grip is very comfortable and secure to hold (one reason it features on many of Extrema Ratio's knives). Despite the amount of meat in the blade it does not feel overly heavy or unbalanced.
![[Image: 39-Extrema-R-Task-J-in-hand-P1260604.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/39-Extrema-R-Task-J-in-hand-P1260604.jpg)
In a reverse grip, the top guard does interfere somewhat with the range of movement, and makes it more difficult to bring the blade back close to your arm.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
Going back for a minute to the sheath, the click-retention makes for a very effective system, the knife can come in and out of the sheath repeatedly, yet despite not using the retention strap, it is held securely and won't fall out. Details like this are not to be underestimated, as working with a knife it is far better to re-sheath it than leave it lying about between cuts, and if you have to move off in a hurry, it stays where it should be and with you. There is nothing flimsy about any aspect of the sheath. Wherever you put it is where it will stay, and it is also fully ambidextrous.
For such a heavy duty blade, the balance is extremely good. It is in front of the first finger, as the balance point sits at the guard itself. This makes it slightly blade heavy, but much less than similar knives, and certainly not fatiguing when using it for finer duties when you want a lighter feel.
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
With there being such a large fire-steel included I was surprised that there wasn't a striker on the blade spine. Extrema Ratio said that with the fire-steel only likely to be used in very rare instances, if needed, the blade edge would be used. Definitely not something I'd want to do, so I'll be grinding a small striker into the spine.
Putting the TASK J next to the Extrema Ratio knife that first drew me to the brand, the Fulcrum. The TASK J's blade is a little wider and shorter than the Fulcrum. With the Fulcrum's double guard next to the TASK J's, also note how the TASK J has lanyard / lashing holes in its guard - more flexibility in the way you can use it. It might have been made for the special forces, but this is firmly in the territory of a tough survival /utility knife.
![[Image: 46-Extrema-R-Task-J-Fulcrum-P1260653.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/46-Extrema-R-Task-J-Fulcrum-P1260653.jpg)
With the TASK being such a good general utility blade, it is no surprise that a special forces unit (the Jagdkommando Unit) were enthusiastic for a heavier version of that blade style, and they certainly got it in the TASK J.
Review Summary
The views expressed in this summary table are from the point of view of the reviewer’s personal use. I am not a member of the armed forces and cannot comment on its use beyond a cutting tool or field/hunting knife.
Something that might be a ‘pro’ for one user can be a ‘con’ for another, so the comments are categorised based on my requirements. You should consider all points and if they could be beneficial to you.
_______________________________________________
Things I like
_______________________________________________
Strong, but well balanced, blade.
Super versatile and effective sheath.
Giant fire-steel included.
Effective and comfortable grip.
Double guard with lashing points.
_______________________________________________
What doesn't work so well for me
_______________________________________________
Blade coating can 'drag' when cutting.
Poor factory edge.
No striker for the fire-steel.
![[Image: 00-Extrema-R-Task-J-feature-P1260639.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/02/00-Extrema-R-Task-J-feature-P1260639.jpg)
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| Rockwell Hardness Difference Calculator |
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Posted by: Mike Brubacher - 02-22-2018, 06:08 PM - Forum: Rockwell C Hardness Calculator
- No Replies
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Brubacher/Svancara Rockwell C Differential Comparitor This calculator computes the change in hardness from one HRC number to another "instructions"> Enter the first HRC value in the box and then the second HRC value in the next box. Click "CALC". Answer will be displayed as a percent (%) change. Click "RESET" to clear boxes. Visit bessex.com for a full explanation of this calculation, or go to edgeonup.com to download this calculator.
Copyright 02/26/2018 Brubacher/Svancara - The above calculator is optimized for Google Chrome Browsers. It may display differently in other browsers.
Comments on the calculator program for determining percentage change of hardness between two Rockwell C hardness numbers
In the thread “Rockwell C Linearity Study” of the BESS Exchange forum we presented a simple formula which tells us the percentage change of hardness between two immediately following HRC numbers (e.g. between HRC 60 and HR 61).
For the use in the hardness difference calculator we derived a equation for determining the relative difference in hardness for two arbitrary Rockwell hardness numbers (e.g. HRC1 = 50 and HRC2 = 60).
The formula looks like this:
![[Image: K8Bvo0i.jpg]](https://i.imgur.com/K8Bvo0i.jpg)
The above equation sums up our efforts expended during the last year on a better understanding of the Rockwell C hardness scale. This equation represents the mathematical formula for determining the relative difference in hardness of one Rockwell C hardness number to another. The above calculator function reports that difference as a percentage. When we first began this project we did not hold out much hope for actually solving the problem of putting the Rockwell C (HRC) into well defined and meaningful terms but rather were hoping just to make it a bit more meaningful in relative terms. Our expectations were tempered by the fact that, simply, this question has been asked for a hundred years and never, to the best of our knowledge, answered. Given the prevalence and commonality of the HRC test method, that would give anyone pause when contemplating this question. In the end though, the question was substantially answered in not one, but three, while related, still different and independent approaches. Since all three of these methods, each independently arrived at, seem to support each other, it gives us some confidence in the correctness of our efforts. In view of the fact that most of us had not even a good idea or guess as to the relevance of one HRC number to another, we feel that the calculator can make a real contribution to our understanding and use of the HRC scale.
The first of our efforts resulted in the generation of a study of the geometric attributes of the HRC indenter itself . That study resulted in the following chart:
![[Image: blhLKr2.jpg]](https://i.imgur.com/blhLKr2.jpg)
This chart calculates and then compares the percentage change in surface area of the HRC indenter in .002mm increments. While this chart does not represent the answer, it does make a significant contribution in setting the path to the answer. The equation listed at the top of this page draws on some of the work done by George and Robert Vickers and incorporates information drawn from elements of the chart. For those who may not be aware, the Vickers uses a very different method than HRC in calculating hardness. Vickers hardness calculations are made by measuring the area of the indentation and then factoring in the force applied. The relevance of the Vickers work to this project can simply be described as this; the Vickers Hardness Scale is linear. Scales that are linear lend immediate and intuitive relevance to their output i.e. assuming that the scale's increases are in an ascending order, then 50 is twice as much as 25 and 100 is four times as much as 25.
![[Image: E34kRjN.jpg]](https://i.imgur.com/E34kRjN.jpg)
The HRC cannot be linear due to the fact that it utilizes a constant force (load) and a constantly changing indenter impingement area. Therefore, materials of various hardness are tested under various circumstances. There is no "apples for apples" with the standard HRC scale unless one is always testing the same hardness of material.
![[Image: hVUa16R.jpg]](https://i.imgur.com/hVUa16R.jpg)
Fortunately the HRC test method does provide us with a key bit of information; we know the depth of indenter penetration into the sample. The force or "load" is constant with the HRC and since the HRC indenter is of a well known geometry, we can then calculate the surface area impinging on the test sample. This then leaves us with more of "Vickers Like" calculation of hardness.
A third checkpoint in this process then is simply this; just as the conversion graph above demonstrates , we can take advantage of the many different types and styles of Vickers to Rockwell C converters available. Many of these seem to vary somewhat in their interpolations but, generally, they support our equation. The process here is a simple one when proving the calculator's general correctness. If the Vickers is linear then its correspondence with any two HRC numbers (within the accuracy constraints of the conversion) must be linear as well. Find a converter and then pick any two HRC values and their corresponding Vickers values. Simply calculate the percentage difference between the two Vickers numbers and compare with our calculator result. Due to the vagaries of the various conversion charts the comparisons aren't likely to be precise but you should find that they are proximate.
Here then is another method and an exercise in comparing our calculator results to our earlier chart results; enter any two HRC values that are immediately proximate to each other i.e. 60-61 or 32-33 and then compare our calculator result to the corresponding chart result. The result will be nearly precise.
Acknowledgement:
Our thanks to Wade Bevan for his help in the construction of this web-based calculator program.
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| Where do knife steels come from? |
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Posted by: EOU - 02-20-2018, 11:38 AM - Forum: All About Edges
- Replies (26)
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Just posted something over in the edge rolling test stand section and it reminded us of a question that our members might be able to expand on. The question has to do with the development of modern steels used in knife making. We've heard that almost no new steels are developed for knives. The steels talked about and used frequently by knife makers and bladesmiths were usually developed for use in other industries. Most notably the tool and die industry. In fact, a very small percentage of these high grade steels are utilized by the knife industry when compared to their original and intended use. High quality steels only find there way to the knife industry when someone in the knife industry "borrows" a newly developed steel because they feel that it might just make a fine knife. The aforementioned is all conjecture as far as we are concerned. Can anyone either elevate or dispute these assertions?
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| "The Mortimer" |
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Posted by: Mark Reich - 02-19-2018, 03:08 PM - Forum: Knife Making & Bladesmithing in Memory of Mark Reich
- Replies (5)
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Since I have finally figured out a simple method to post pictures, I will now be posting pictures regularly.
This is specifically in response to Mr. Grepper's call for re-posting pictures that got erased by the miserable photobucket fiasco.
It's the best full tang knife I've ever made, which is easily one of the best blades I've ever finished.
This knife was commissioned by a Gentleman I hold in very high esteem. I get to call him "Family" because we are that close, and we've always been that close. His family lived next door to my Mom's folks, and the Mortimers and Richards kids (Jim and Sam Mortimer, my Mom, Aunt and Uncle) grew up together, and are inseparable.
There is something about this knife that draws people, and those who hold it in their hands are always inspired. It's heft and balance, the organic beauty of the blade, the ancient mammoth tooth and mammoth ivory, combine into something far greater than the sum of the materials.
I'm fairly certain this knife will find it's way into an article in Knife Magazine within the next few months. If you're familiar with knife publications, that will mean much more than I'm capable of expressing. Blade magazine may be popular, but I wouldn't use it in the outhouse.
I'm not much of a photographer, so these will have to suffice for now.
![[Image: gGSMf3y.jpg]](https://i.imgur.com/gGSMf3y.jpg)
![[Image: 3OOMAfG.jpg]](https://i.imgur.com/3OOMAfG.jpg)
![[Image: JT43pPO.jpg]](https://i.imgur.com/JT43pPO.jpg)
![[Image: VcvdyK6.jpg]](https://i.imgur.com/VcvdyK6.jpg)
![[Image: j8dGQih.jpg]](https://i.imgur.com/j8dGQih.jpg)
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| Knife Review: Lionsteel T5 MI |
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Posted by: subwoofer - 02-19-2018, 09:22 AM - Forum: Knife and Blade Reviews
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![[Image: 00v2-Lionsteel-T5-Feature-P1260728-.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/00v2-Lionsteel-T5-Feature-P1260728-.jpg)
Each year at IWA, there are a few blades that stand out and draw you back to them time and again. Lionsteel's T5 was one of those, and may well have been my most visited blade at IWA 2017. I've been fortunate enough to be able to spend a lot more time with it subsequently, as well as being able to discuss its design with Mik Molletta, the man behind this outstanding knife.
![[Image: 32-Lionsteel-T5-with-sheath-P1260830.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/32-Lionsteel-T5-with-sheath-P1260830.jpg)
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Author's Statement for Transparency and Disclosure
The test sample/s featured in this article have been provided for technical testing and review by the manufacturer. Test samples are retained by the reviewer following publication of the completed review for the purposes of long term testing and product comparisons.
All output figures and test results published in this review are the sole work of the reviewer, and are carried out independently and without bias. Test results are reported as found, with no embellishments or alteration. Though best endeavours are made to maintain the accuracy of test equipment, the accuracy of these results is not guaranteed and is subject to the test equipment functioning correctly.
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The Blade and Handle Geometry:
Most knife specifications have a basic description of the blade geometry, but in this section I will be taking a more detailed look at geometry and balance.
![[Image: 34-Lionsteel-T5-grind-P1270890.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/34-Lionsteel-T5-grind-P1270890.jpg)
Using a set of gauges and precision measuring equipment including a Vernier protractor, callipers, fixed radius gauges and the unique Arc Master adjustable radius gauge (the one that looks like a crossbow).
![[Image: Knife-measuring-P1180483.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/09/Knife-measuring-P1180483.jpg)
These measurements have been tabulated and are presented along with a few reference blades (8" Chef's Knife, 5.5" Santoku and the popular Fällkniven F1).
Key aspects such as the primary bevel angle, grind type, blade depth, blade thickness, length, weight are detailed, along with balance information.
![[Image: 35-Lionsteel-T5-bevel-P1270895.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/35-Lionsteel-T5-bevel-P1270895.jpg)
The 'Balance relative to the front of the handle' tells you if the knife will feel front heavy, or if the weight is in your hand (a positive value means the weight is forward of the front of the handle). The 'Balance relative to the centre of the handle' indicates how close to a 'neutral balance' the knife has in the hand.
![[Image: 33-Lionsteel-T5-balance-P1270886.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/33-Lionsteel-T5-balance-P1270886.jpg)
In the case of full convex grinds the approximate centre of the grind is used for the primary bevel angle estimate.
![[Image: More-Marker-V2-100h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-100h.png)
(Wherever you see the 'Read MORE' marker, it indicates that the Extended Version of the review has additional content at that point. Viewing the extended version helps support further reviews, but please ensure you return to this Forum for comments and discussion.)
The blade is made from Niolox steel.
New for 2018! BESS Certified sharpness testing:
The BESS 'C' scale of sharpness, developed by Mike Brubacher (Brubacher Edge Sharpness Scale) will now become part of Tactical Reviews' knife testing process. Initially this will be used to verify the sharpness of the factory edge and allow the knife to be brought to a minimum standard sharpness before testing a blade's cutting performance.
The Lionsteel T5's factory edge has an average BESS 'C' sharpness of 233. This original edge cleanly slices 80gsm copier paper with an edge cut, but won't quite push cut it. It slices into the rounded edge of a doubled over sheet of the same 80gsm paper. It also will catch the edge of green Rizla paper and slice halfway through (cross ways), but not all the way.
![[Image: 36-Lionsteel-T5-BESS-PSX_20180210_163819.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/36-Lionsteel-T5-BESS-PSX_20180210_163819.jpg)
Explained by the Maker:
The reasons for certain design choices may not be clear when simply looking at an object, so this section is intended to give an insight into the thinking behind a design by speaking to the designer themselves.
Mik Molletta, kindly agreed to go through many of the design aspects of the T5 and despite a language barrier, Mik has helped with the questions I put to him:
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
A few more details:
The T5 arrives in a cardboard box.
![[Image: 01-Lionsteel-T5-box-P1260656.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/01-Lionsteel-T5-box-P1260656.jpg)
Inside, the sheathed T5 is otherwise unwrapped.
![[Image: 02-Lionsteel-T5-box-open-P1260664.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/02-Lionsteel-T5-box-open-P1260664.jpg)
Along with the T5 is a small leaflet.
![[Image: 03-Lionsteel-T5-box-contents-P1260672.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/03-Lionsteel-T5-box-contents-P1260672.jpg)
However, the blade is wrapped inside the sheath.
![[Image: 04-Lionsteel-T5-sheath-retention-P1260674.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/04-Lionsteel-T5-sheath-retention-P1260674.jpg)
You can see that the plastic wrapping was not terribly successful, as the blade has just sliced through it when it was inserted into the sheath.
![[Image: 05-Lionsteel-T5-blade-wrap-P1260679.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/05-Lionsteel-T5-blade-wrap-P1260679.jpg)
A very nice quality leather sheath is used for the T5.
![[Image: 06-Lionsteel-T5-leather-sheath-P1260683.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/06-Lionsteel-T5-leather-sheath-P1260683.jpg)
The leather is double stitched for maximum durability and lifespan.
![[Image: 07-Lionsteel-T5-leather-stitching-P1260686.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/07-Lionsteel-T5-leather-stitching-P1260686.jpg)
The maker is cleanly embossed into the leather.
![[Image: 08-Lionsteel-T5-leather-embossed-P1260692.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/08-Lionsteel-T5-leather-embossed-P1260692.jpg)
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
A great looking knife and sheath. This is why I kept revisiting Lionsteel's stand at IWA 2017.
![[Image: 12-Lionsteel-T5-and-sheath-P1260718.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/12-Lionsteel-T5-and-sheath-P1260718.jpg)
The steel specification is engraved into the blade - NIOLOX. An increasingly popular steel.
![[Image: 14-Lionsteel-T5-and-steel-P1260735.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/14-Lionsteel-T5-and-steel-P1260735.jpg)
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
The flat grind is very high, but not quite a full flat grind.
![[Image: 17-Lionsteel-T5-blade-P1260746.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/17-Lionsteel-T5-blade-P1260746.jpg)
Only visible along the back of the handle, there is a full length, full thickness tang.
![[Image: 18-Lionsteel-T5-blade-back-P1260749.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/18-Lionsteel-T5-blade-back-P1260749.jpg)
Sculpted from a single piece of micarta, the handle has a wide and comfortable finger guard. The cutting edge is nicely terminated with a sharpening choil.
![[Image: 19-Lionsteel-T5-handle-detail-P1260756.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/19-Lionsteel-T5-handle-detail-P1260756.jpg)
Grip texturing is machined into the handle surface.
![[Image: 20-Lionsteel-T5-handle-bolt-P1260760.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/20-Lionsteel-T5-handle-bolt-P1260760.jpg)
Two stainless Torx bolts secure the handle to the tang.
![[Image: 21-Lionsteel-T5-handle-P1260766.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/21-Lionsteel-T5-handle-P1260766.jpg)
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
With a well rounded plunge line, maximum strength is retained.
![[Image: 25-Lionsteel-T5-plunge-P1260788.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/25-Lionsteel-T5-plunge-P1260788.jpg)
Excellent attention to detail in the sheath with a protective cover over the internal part of the rivets. Doing this prevents the handle being scratched by the metal fixings.
![[Image: 28-Lionsteel-T5-sheath-detail-protection-P1260811.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/28-Lionsteel-T5-sheath-detail-protection-P1260811.jpg)
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
This really is something special.
![[Image: 31-Lionsteel-T5-with-sheath-P1260823.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/31-Lionsteel-T5-with-sheath-P1260823.jpg)
What it is like to use?
I'm going to start with that beautiful and well thought out leather sheath. Fortunately I am right handed, so this presents me with no issues, and I hope Lionsteel will offer a left handed version of the sheath.
It is the first MOLLE compatible production knife leather sheath I've come across, and makes an excellent change from the typical MOLLE compatible sheaths. Some MOLLE mounts are more of a struggle to use than others, and this sheath is a bit of a battle to fit. It is definitely worth planning out the position carefully as I did not enjoy fitting or removing it. The webbing on the sheath that fits over the leather MOLLE strap is quite tight, and catches firmly on the edge of the press stud when you try to slide the strap out. Easy enough when the sheath is not mounted, but definitely a struggle when trying to unmount it.
The sheath wraps over the first part of the handle with the retaining strap fitting above the finger guard. This over-wrap serves two purposes, the first is a very secure hold on the knife, and the second is that the over-wrap helps keep the retaining strap out of the way of the blade edge as it is sheathed and unsheathed.
![[Image: 13-Lionsteel-T5-and-sheath-P1260723.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/13-Lionsteel-T5-and-sheath-P1260723.jpg)
With its 5mm blade stock, the T5 has a bit of weight to it, but that fantastic sculpted handle allows it to sit in your hand so comfortably. For a multi-purpose blade, the extra weight from the thick blade is the small trade off for the gain in strength and robustness you want in a blade that might be used for just about anything.
![[Image: 26-Lionsteel-T5-in-hand-P1260798.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/26-Lionsteel-T5-in-hand-P1260798.jpg)
![[Image: More-Marker-V2-50h.png]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2017/07/More-Marker-V2-50h.png)
Factory edges are a subject unto themselves, as for some it is the best edge they ever have on that knife, and for others the worst. On the T5, the factory edge was impressive, and definitely usable out of the box. Due to the blade thickness, the edge bevels are quite wide and this will only get more pronounced with further use, but is the norm for blades of this thickness.
Mik Molletta has done Lionsteel proud with this design, and Lionsteel have done Mik Molletta proud with the quality of manufacture of his design, and this knife, that stood out from the crowd at IWA 2017, continues to impress the more I use it. The full package is a pleasure to use, and has put itself firmly into my top 5 favourite fixed blades.
Review Summary
The views expressed in this summary table are from the point of view of the reviewer’s personal use. I am not a member of the armed forces and cannot comment on its use beyond a cutting tool or field/hunting knife.
Something that might be a ‘pro’ for one user can be a ‘con’ for another, so the comments are categorised based on my requirements. You should consider all points and if they could be beneficial to you.
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Things I like
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Sculpted one piece micarta handle.
Strong 5mm blade stock.
NIOLOX steel.
Super quality, double-stitched leather sheath.
High Flat Grind, multi-purpose blade.
MOLLE compatible sheath.
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What doesn't work so well for me
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Sheath is right handed only.
MOLLE Strap more fiddly than most.
Thick blade results in a wide edge bevel.
![[Image: 00-Lionsteel-T5-Feature-P1260729v2.jpg]](http://tacticalreviews.co.uk/wp/wp-content/uploads/2018/01/00-Lionsteel-T5-Feature-P1260729v2.jpg)
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