Tag Archives: Sharpening

Knife conversation part 1 — Sharpening !!

20171012_105624-014060260.jpeg

Nemo: when you buy a knife you will be sooner or later, depending of many factors, confronted to a dull edge. Getting away from the factory edge is like leaving your parent’s home: it’s uncharted territory for most of us. So should you waith for the knife to be dull or immediatly hit the stones to make it yours and why ?

cropped-p1070881.jpg

JD: When I get a new knife I check the edge to see what condition it is in. I pinch it between my fingers to see how thick it how thick the blade is just behind the edge. And just look at the edge see if the edge bevel is even. Some times you can see unevenness close to the ricasso. That will take some extra attention and work on the hone to get right. I use light to see if it reflects of the edge, if it does there is a dull spot. Then I check for a burr with my thump nail.
20171010_125828-01177728853.jpeg

If there is a burr I take a hone, usually the diamond side of the Fallkniven DC4, and remove it. Now I take a receipt of shopping, they are usually thin and consistent, and try push cutting and slicing it. If it cuts the paper cleanly and easily it is good enough to start using. If not, then I will sharpen it first. Depending on edge thickness, edge angle, and steel and what I feel like (knives are a hobby for me!) I will pic a hone and start sharpening.

20171004_180416-011239339540.jpeg

Nemo: knowing sharpening is your hobby is a knife easy to get dull a dream for you ? Or do you prefer your sharp edge to remain sharp for a long time ?
Would you enjoy D2 more than Elmax ?

20171012_104749-0277866023.jpeg

JD: a knife is for cutting and it cut better when sharp. I prefer a sharp knife! 🙂 It needs to cut what I need to cut with ease otherwise it is back to the hone it goes! I also like a knife that when it looses sharpness is easy to get sharp again. So I have no need for high wear resistant steels. But if they are thin at the edge and I like the rest of the knife it would not hold me back either.
If they are both well heat treated and kept cool in production and sharpening there after, both D2 and Elmax would work fine form me. I do not think I could tell them apart in use or sharpening. I am not much of a steel junky, though I like reading about the science of how steel works in knives. (I highly recommend the following books: (in German) Roman Landes: Messerklingen und Stahl and (in English): John D. Verhoeven: Metallurgy of Steel for Bladesmiths!) For me blade geometry and sharpness make a relevant difference. I can tell a thick knife from a thin knife and a dull one from a sharp one far better than the edge retention one steel from another.

20171011_151451-011592961934.jpeg

The biggest differences in steel that I notice are, first, how they sharpen, how easy or hard it is to remove steel, and second, how stainless they are. The last bit mostly when cutting fruit.

wpid-CameraZOOM-20120314164015602.jpg

Nemo: Sharpening wise: what would be the main difference between hollow ground knives and flat grind ?

JD: If they are the same thickness behind the edge the hollow ground blade wil take less effort to make the blade even thinner behind the edge, and take less effort to keep the blade thin behind the edge. Hollow ground knives can be laid flat on a hone to make and keep them thin. I have done this with a few knives. One of them a Spyderco Salt1. Now it is almost a single bevel grind (‘scandi’) and much thinner behind the edge. This has made it cut a lot better.  

The same can be done with a knife with flat bevels, it just takes more work. When you use and sharpen a knife for a while the edge gets closer to the back of the blade and gets thicker. When it gets thicker it cut worse. To make it cut well again the area behind the edge needs to be thinned out. As a hollow ground knife has less steel behind the edge it takes less work to keep it thin behind the edge.

On flat ground you often need to remove the scratches after …

20171012_103055-011631308535.jpeg

 

 

Zero Tolerance 0562CF — Bright and Beautiful.

wp-image-1933490811 My first Zero Tolerance was the 0770CF and I was really amazed by the quality of manufacturing provided by that Peter Kershaw’s brand. But I wanted something hardchore, heavier at the opposite of my C36 Military which is light and fast like the Hussein Bolt of knives. I have given a chance to the Megalodon, Real Steel flagship. But a poorly designed clip ruined my experience. So I have asked some advice on the Zero Tolerance Facebook group and I have invested in a ZT0562CF ! RIL lock, deep carry dark clip, no hot spot on the handle. The attention to detail is amazing and the ooze of quality. Designed by Rick Hinderer it has won Best American Made Knife at the Blade Show some years ago.

It’s a true flipper, the “thumb” studs cannot be used to open the blade as the detent is too strong. They are just here to be part of the lock. Their also a stop pin but it’s only used to stop the blade once closed not opened.
The first edition of the Real Steel Megalodon used to have the same system and the handle kept that “S” on the front which form two horns which can used as deterrent in case of self defense situation.wp-image-1687282944 As you can notice, it’s easy to pinch your finger between the stud and the handle when opening the blade. So really, it’s a true flipper made to be open in that way. And here the experience is wonderful. The smooth KVT ball-bearing opening system. A washer with caged ball bearings surrounds the pivot and makes opening the knife nearly frictionless. Only the detent ball brings some minor friction actually. But it’s really minimal. The knife opens every time. The balance is perfect, just behind the pivot. So the blade is alive in my hand. wp-image-133474584 What you noticed first when handling the ZT0562CF is her smooth Carbon Fibers scale and butter like action. It’s 156 grams heavy compared to my Military 120 grams (titanium clip)… You fee the heft. And that’s exactly what I wanted. The corners are chanfered and there is no hot spots even the clip is not felt in hammer grip. I love the details on the blade: the stonewashed flat side and the satine grind. wp-image-748540201 It offers alsmot the same working edge. It carries tip up and it’s not as fast to draw as the Millie even with its titanium deep carry clip. The blade is made of CPM 20CV but it was first offered in M390 and CTS204P like on the Spyderco Southard. “CPM-20CV has a high volume of vanadium carbides and a high amount of chromium. You get exceptional edge retention and outstanding corrosion resistance.” said Zero Tolerance site. In fact CPM-20CV is the twin brother of M390 and CTS204P. Different manufacturer and same super steel with at 1.9% carbon, 20.0% chromium, 1.0% molybdenum, 4.0% vanadium, 0.3% silicon, 0.6% tungsten, and 0.3% manganese. The heat treating and the grind will make the difference. But as a Powder Metallurgy (PM) tool steel, you should get a combination of impressive wear resistance and edge retention plus the added benefit of being highly corrosion resistant due to its high level of chromium. wp-image-36373330 You can notice the different surface works on that picture. But as far as the blade was beautiful I felt the edge was thick compared to what I’m used too.

And unfortunatly the ZT did not pass my Plastic Bottle Butt’s test ! It was blocked and even a saw motion did not change anything. The blade was stuck before to reach the thicker part. So I had to summon: the diamonds, the sandpaper and the ceramics and put on thinner edge on that beast of a knife.

wp-image-170153826 I have started with the diamonds of the Fallkniven DC4. It was not easy as I felt the thumb studs was going in the way. eventually I was able to de-shoulder the edge and even to scratch the blade. That “Hinderer flat-ground “slicer” grind” that should provide both slicing efficiency and a tough point was not easy to get at first. wp-image-908967677 Against the scratches I has used a P1000 Sandpaper and they were erased. No big deal. They have disappeared just but doing an 90° motion. I have treated all the blade for good measure. wp-image-737758906 Then came the work on the brown stone, the brown ceramic and the white ceramic. My edge was slowly going convexed. My favorite one for stropping. Soon CPM-20CV was back to razor. I was amazed by the way the steel react under the ceramic. It was much easier than I thought. I had the same excellent experience with my Southard.

Then came the leather work with some polish white paste and I was able to achieve a nice mirror finish. At all it took me one hour for thinning and polishing the edge to my own taste. wp-image-1937876634 wp-image-1775073832 True convex razor as the hairs were jumping on the blade.

It was time to test it on the Coke bottle butt again:

And this time it was a success ! The blade pushcuts steadily through the thick transparent plastic. And then on tomatoes skin which can be tricky with a polish edge.

Some mozarella slices… with its open construction it was a breeze to clean under the tap.

And eventually all the ingredients wre turned into a salad for lunch. Conclusion: the ZT0562CF is now in my pocket to be tested on a longer run but it already got such great qualities to make it a keeper: unearthy smooth operation, great ergos, best high tech materials and top notch steel. The thumb stud does not get in the way while cutting and the point is strong enough to feel confident about its resilience. The innovative deep carry clip makes it easy to disappear in the pocket. It’s the perfect adequation between hard working and gentleman folder. Now you can also check the Falcon here which is a true jewel in that flipping matter.

wp-image-1719208375

wp-image-1909485844

Endura HAP40 blade and Pakkawood handle, sanded to my taste.

wp-image-1364064139

The tools of the trade. Leather belts, sandpaper sheaths and coffee.
As usual I cannot let ma knife as provided by the factory and Pakkawood being a synthetic ersatz of wood, I wanted to see how it reacted under the sandpaper.

P500 Metal sandpaper is used just to round the facets into rounds. The Pakkawood is soft and it’s done without any kind of discoloration. It reacts a lot like Micarata. No smell.
Anyway I was holding my breath. Those dusts are unhealthy.

“If you have a buffing wheel, try polishing the wood handle – it buffs up beautifully with a XAM or green rouge compound.” said to me Howard Korn.

wp-image-128584173

Then I take the chance to sand the edge of the liners. It always great to feel an handle with not sharp edge. I have done also the same with the hole. I don’t want to chanfered it like on the AFCK but less edge makes my thumb safer. Remember, I was bite by the Tatanka hole once.

I have sand the spine to smooth it and then used some polish on leather to remove the sharpening scratches.
Eventually I have turn the Endura into a great razor which has be baptised with my blood for good measure. (I happen during the stropping…)

wp-image-1702930307

On the edge of the Polestar by JD

Like Nemo I have received my Polestar as a gift from Spyderco. It was in the goodie bag at the 2017 Amsterdam Meet. When I took the knife out of the box and looked it over my first impressions were positive. The blade opened smoothly and locked solidly with the lock bar fully engaging the tang. I liked how the gray G10 looked and felt, a nice combination of grippy and smooth. Clip tension was also excellent. I could slide the knife in and out of the pocket and waistband without any problem. The edge it came with from was less impressive, it could push cut receipt paper but had no slicing aggression at all.

When I came home I put a drop of Nano oil on the pivot which made it even smoother. I could flip the knife open with my middle finger, which is a lot of fun! Other than flipping it a few times I didn’t know what to do with Polestar. For me it is quite a big knife, having a blade length of 8,5cm. In my urban environment and with my use I have found that a blade length between 5-7 is ample. Small knives are often just more convenient for me.

After a few weeks of from time to time picking it up and flipping it I decided to give it a try and see how I would like to carry and use it. Like Nemo I moved the clip to the tip down position. I was going to carry it in the waistband and tip down carry reduces the chances of the blade accidentally opening. Thanks to the Spyder hole hump it could still be easily and quickly opened with the Spydie drop.

Before I was going to use it the edge would need to have more slicing bite then it did new. So, I thought a few passes on a coarse DMT hone would be enough for a quick touch up. I was wrong! I found out that, especially close to the recasso, the edge was pretty uneven. In some places it was even a high angle convex. The edge would need to be formed anew!

I cut of the old edge with a few light cuts into a stone and then created a new edge with my extra coarse DMT hone. I was interested in how the knife would function as it was intended by Spyderco. So I did not change the angle of the edge much but just evened out the edge bevel and formed a new apex. The steel was not hard to grind but, due to the unevenness, some parts needed lots more work than other parts. After I had was sure of having formed an apex by creating a burr on either side of the edge, I removed as much of the burr as I could by using alternate and high angle strokes. The burr flip flopped from site to side a lot and was not easy to cut of. Once I had removed most of the burr on the extra coarse hone I repeated the procedure on the fine DMT with the same difficulty in removing the burr. At that time the edge would slice receipt paper well but I have had better edges.

From past experiences I know that often a new knife needs to be sharpened a few times before the edge reaches its full sharpness and edge holding potential. So, this did not disturb me much. It was to early for conclusions.

I proceeded to cut up some cardboard before repeating most of the afore mentioned sharpening procedure. Only this time I finished on the diamond side of the Fallknives DC4, one of my favorite hones, to an edge that would just split head hair. Removing the burr and finishing the edge had become a bit easier this time around. Over the following days I carried this knife and used it for my normal cutting tasks. Mostly cutting paper cardboard and plastic packaging material and perhaps a bread bun for lunch. A funny thing I noticed: the edge its cutting ability seemed to first increase, then settle down, before slowly starting to dull!

After about a week of use the edge would still work for most of my cutting tasks but had lost some of its sharpness. I decided to resharpen the edge with just the diamond side of the Fallkniven hone again. Getting it sharp enough to shave arm hair was easy but getting it to split head hair still proved to be a bit fiddly, although I did managed it in the end. By comparison: my Elmax Squeak went from not biting in to the hair to cutting the hair with much less effort. A few passes on the hone did the trick there.

Normally I would have put the knife in pocket pocket as it was sharp enough for me use, but out of curiosity and to check my findings I resharpened it once more. I had become a bit easier to remove the burr and to make the edge arm hair shaving sharp. But to get the edge to split head hair was still a challenge. With other knives like my Maniago Spyderco’s in N690 and Elmax and, for instance, my Victorinox Bantam this had never been this difficult.

Overall the Spyderco Polestar is an enjoyable and capable knife: flipping the blade open with the middle finger is still fun and the handle works well, it handled my cutting tasks fine ones I got it sharp, but I am not impressed with the condition of the steel at the edge on my example. Still, it was interesting playing around with a knife that is so different from my usual fare!

JD

JD’S SPYDERCO LADYBUG IN SUPER BLUE STEEL LGYP3E

JD LADYBUG
 

Thanks to my friend Nemo I have had a chance to check out the Spyderco C(SB) steel with a full flat grind(ffg). This is my first ffg Ladybug and my first experience of Super Blue steel. Let me tell you what I found!


I have had a Ladybug before. The VG10 model with the saber grind.I did not like how it cut, for my taste it was far to thick at the edge and the back. I ground the bevels flat so now it has a singe bevel grind. It cut much better but I did not use it much.

The day I brought the Ladybug SB in to service I put a fob on it, Spyderco Jur style, to give me a little extra to hold on to. I oiled the joint with a little Nano Oil. The mid-lock was smooth and easy to operate. There was just a little vertical blade play. Which is not uncommon on mid-locks and back-locks. My older Ladybug was the same in that regard.

I then sharpened it, as the edge was only cutting note book paper roughly. At the same time I lowered the edge angle. When I sharpened the back the of blade, the part above the Spyderco hole, was about 1mm above the hone. This gave me a final edge that was just below 10dps(degrees per side) blended into the main bevel.

My idea is that a knife this small should cut with very little resistence. You are not going to put much force on the blade as the handle is to small for that. So, thin and sharp is the way to go! Grinding the whole blade flat on the stone would make it cut even better but is just to much work for me.

I cut a little cardboard just so see how well it would cut, how the edge would respond, and how the handle would feel in the hand. The blade cut well with little resistance but the edge had collapsed. After de-stressing the edge (lightly cutting in to a stone to remove the damaged steel) and resharpening it I cut some more cardboard. The edge seemed to be stable but more cardboard cutting revealed a small section had collapsed again. It took a few times de-stressing and resharpening to stabilize also this part of the edge. It has been my experience that often a knife need to be sharpened a few times before you see its full potential.

These sharpening sessions gave me the opportunity to use different hones to sharpen the blade. And I must say: this is a very nice steel to sharpen! No matter the hone. I sharpened with diamonds, a Norton fine India hone, and different ceramics. After de-stressing it could be apexed quickly with hardly any burrs forming. The burrs that did form could be removed with just a few light, high angle, passes into the stone. It was not just easy to sharpen, but easily took very sharp, hungry, edge! 🙂

The handle is large enough for me to get a two and a halve finger grip. During the cutting task I used the knife for, I found the handle to give me a good grip and precise control of the edge. I did find the handle small and fiddly for opening the knife with the thump in the Spyderco hole. So, usually I opened the knife in a different way.

The last few weeks I cut medium size apples, cardboard, I opened mail, cut open and removed the seed from and avocado, trimmed a nail here and there, and cut plastic food packaging. The knife handled all these task without much of a fuss, though the apple was at the limit of its abilities due to the length of the edge and the size of apple. Some of these task would have been easier or faster done with a larger knife, but you do not alway have that option. In those cases it is nice to know that this, slightly modified, ffg Ladybug will get the job done. As the saying goes: „I does not have to be big, just sharp!” As for the steel…It takes a great edge! 🙂

Text and Photos by JD.