Kershaw Blur in SG2 steel. Weekend testing review

[STR]

Hi folks. This is long. Its three days worth of notes all in two posts. I hope you like reading.

First Impressions:

Blade measures 3 and 3/8" and is 1" wide blade in plain edge, with a primary grind thickness measurment of.023" right above the edge bevel. It is a very nice grind uniform and the same thickness plus or minus .005 over the length of the blade. I found more variance in other knives from Kershaw and other manufacturers than this but this one is basically the same thickness on the tip third as it is in the middle third as it is at the back third of the blade based on my digital caliper. Its as sharp out of the box as any knife I've seen to date from Kershaw. The pocket clip flipped to tip up for me no problem and mounts both positions just fine. Pretty smart the way Kershaw incorporated the same clip used on the Leek in this design.

Overall fit and finish is excellent as is typical of the knives I have seen from Kai. All pins and screws are centered perfectly. The recess depth of the stop pin is the same on both sides of the folder and the pin does not move back and forth when the blade is moved off it to free it up like I have seen on other models and as a result it doesn't rattle which is good. It weighs in at 3.8 ounces which is a nice heft and yet still light weight enough for comfortable carry. The brown color is particularly appealing and the grip inserts are comfortable and attractive. Blade opens with authority, and there is no play at all with the blade either vertically or laterally.


I note on the Blur that the detent ball works because you can see the lock move in when the ball falls in the hole as the blade is closed. Good move on Kai'/Kershaw's part there. I like seeing that. Its good that Kershaw is now using the detent ball on these assisted openers as you would on any non assisted liner or frame locking knife. I talked with Ken Onion about this years ago on his forum suggesting that Kershaw do this when I noticed my own Scallion did not have the hole drilled in the blade for the ball to fall into. I always thought this was a recipe for a knife opening in the pocket if the spring ever broke, particularly in tip up carry mode. Sure enough it was because I experienced having to make one of my own AO knives a safe queen while waiting for Kershaw to mail out a new spring for it the first time it broke on me. It was either that or tighten the pivot down to make it hard to open or drill the detent hole in the blade, which I did do eventually anyway. I should point out that I have also drilled the hole in the blade to activate the detent on more than a handful of AO Kershaw knives for forum members over the years. Ken and I discussed this on his forum about the Scallion I owned then and he told me then that the only reason a detent was used was to make it smoother opening than it would be rubbing the whole side of the lock as the blade pivots. I agreed with that reasoning but suggested to him in a private message at that time that he and Kershaw consider the gravity knife factor for when the spring breaks. I'm not sure he ever saw it because the thread died after that and he never replied to me about the PM. Maybe he didn't appreciate it I don't know. Then again perhaps he never saw it.


Ok, thats some thoughts on the knife. Now on to use tests.

Hemp cutting with the SG2 blade:

My initial thoughts right after getting it and cutting with it in some hemp rope were that the edge was showing early signs of some reflection in sunlight. Continuing on, after 15 slices it surprised me once again at how much blunted edge reflected back at me already under the light at the tip third portion of the blade which is what I used on the SG2 blade to do the cuts. I made note of it and went on though. The real surprise came after 165 more push cuts and slices clean through the half inch hemp using that same tip third of the blade only to do all my cutting. To my surprise the edge at that section still looked exactly the same to me as it did after the first 15 cuts. In other words those early deflections I saw initially had no negative affect in cutting performance and remained relatively unchanged.


All these cuts were bare handed by the way. If there is one thing worth noting right away its that the Blur is very comfortable to use. Right up there with, if not surpassing the comfort in the hand that I get with the JYDII which I think is the best knife Kershaw currently makes in a folder for a number of reasons. I did a lot of cuts bare handed with this one. In fact it was so comfortable that it surprised me how far I could go with it bare handed. Thanks to that comfort and the edge keeping I made it farther than ever before when cutting hemp with a Kershaw knife bare handed. Finally after around 130 bare hand pushes into the hemp the blade and handle did begin to wear into me causing some discomfort on my hand and fingers to where I noticed it like other knife handles have with much fewer cuts.


I started to write that it was getting harder to cut from the blade dulling down at around 125/130 slices on up to the end.

However, I am left wondering if it actually was more difficult due to dulling or if maybe I was just getting muscle fatique after all 180 cuts with this blade bare handed. I wondered to myself mumbling if the increase in effort I percieved was due to my own fatique from doing so many cuts and not anything to do with the blade dulling. The blade appears to still have lots and lots of life left in it and does not need a touch up at this point after that many cuts in the hemp. Due to this I believe the knife is fine and that the percieved increase in difficulty was more with me than the edge. Now to find that out. For this I'm going to do another type of test.

Moving on to cardboard since I was fatiqued: Here the blade also excelled well. I only do this test when I have the supplies and when I am fatiqued. What I do is save my old toilet paper roll cardboard centers from both our bathrooms. These old cardboard roll centers are wonderful for getting an idea of how much an edge changes with use without having to wear yourself out to worry so much about that fatique factor changing the perception of difficulty. It appears the blade is capable of going farther in hemp than a human being is before the knife wears him out so this will help me know if that is the case or not. In other words I am thinking the blade is far more capable than the user here. The knife did so well in the hemp that I wanted to gauge another view of the edge so I could decide if the edge was really dulling any or if it was just me. I moved on to this test that I have done before with good results in order to find that out. The only difference here is that the blade wasn't fresh but used first for other cuts in hemp.

You can do this two ways with the cardoard TP holders. Some cut rings off the ends making like tomato slices over and over but I hold the cardboard center upright so its vertical and slice down letting the knife do the work.The first two slices cut the tube of cardboard in half length wise. It requires very little force for this test because physical exertion is nil. But it requires a very sharp edge to do it continually and some mental focus since very little pressure is being applied and you are slicing thin delicate slices of card. The SG2 blade steel is impressive starting out here doing this even after all the hemp cutting!

After I reached roll number 25 I began to see some changes in the edge. By the way, each roll consisted on average of 12 to 15 slices each before moving onto the next one. Once the tube was cut in half I then half it again and then slice off thin slivers from the sides of each half until the slices are so small its hard to hold onto the remaining card standing upright the height of the original paper roll and even harder for the blade to cut it rather than kink it. The blade was finally beginning to show signs of folding or kinking the cardboard down consistantly rather than cut into it to start the cut after getting midway through roll number 25 or after around 336 to 350 slices plus or minus which are the first indicators that the edge is blunting a bit and starting to be affected by the cardboard, and in this case the hemp also since that was cut first with the blade before moving to this test. Cardboard of this type that is recycled is full of fibers both natural and man made, as well as untold amounts of silica, mica, and glues, among other things and can be a good medium to test the edge of a knife with.

The delicate nature of this thin card these rolls are made of allows me to see pretty close to exactly when the knife's edge changes and not so much when I get fatiqued or sore. This way I have what I feel is a better idea of when the blade is no longer as sharp with little worry that it might be my own fatique that is causing me to think the blade changed in performance. Granted this is no CATRA test but its the best way I could figure to judge the edge here. The SG2 blade did quite well here, especially when you consider that it cut 180 times in half inch hemp rope with that same tip third that I did these cardboard cuts with.

For all the testing so far only the 1 and 1/8" tip third of the blade was used to do any cutting, both the belly third and the back third of the blade are still factory fresh at this stage of the testing. I ended up using up all 28 cardboard rolls I had saved over time and had quite a pile of sliced cardboard on the floor when done. The last three rolls required a bit more focus to insure I didn't cut myself though since the blade steadily got harder and harder to get started in a new slice without kinking the card over rather than cut into it. Once I started seeing the rim of the roll kink rather than the blade slide through effortlessly I can count up how many cuts it made before dulling down to gauge it against others I've done this with. As it sits I did between 336 and 350 slices of thin strips of card board with it after doing 180push cuts, bottom slices through half inch hemp rope. In the past some knives have only made it to 15 rolls from a fresh start. Going back to the hemp after taking this break to push cut five more times through a left over I can see that it did dull down a good bit at this point. Its much harder now to cut the hemp rope than it was before I stopped the rope cutting in the first series of cuts.

I like this method of testing the edge because it allows me to zero in on one area of the blade only so I only use the one specific area for all the cutting I am doing leaving the other two thirds of the blade edge pristine. I sometimes actually mark the thirds of the blades with a Sharpy magic marker as was the case here. When I start to think I'm seeing a difference in cutting performance in the area of the blade I'm cutting with I can then cut once in the roll or the rope, carpet or whatever with the factory fresh third of the blade in a new spot to gauge a comparison. Using a different third of the knife blade to get a comparison going in my mind so I can see life expectancy of the edge is not so important in this case as it was to determine if what I was seeing was blade dulling or Steve dulling. But in my mind this allows me to compare it with other steels I've done this with. Bottom line here is that the SG2 has a very impressive showing so far.

What this test with the cardboard tells me is that the increased effort I was feeling in rope cutting was me and that the blade still had lots and lots of clean cuts with less effort in it when I switched tests. The percieved effort increase cutting the hemp had to be me getting tired, sore and worn from doing it so many times bare handed. This is a pretty good blade steel folks!

I don't think it would be a problem to cut 1000 or 1500 times in half inch hemp rope using this blade if you used the entire blade in thirds in this manner. In fact I'm sure it could do that and then some after using it. It appears to me to be award winning performance here for edge holding.

 

[STR]

Saturday testing continued:

AM testing.

Moving on to thicker cardboard boxes: The handle again was very comfortable and the lock seemed secure and strong all through the cutting. At no point did I note the lock bending as I have with the Spyderco Miliary, or the Rat Trap folder for example when doing this same test. Not that this is a bad thing mind you, just noted for the record. The main thing is the lock slipping to look out for here. That is bad! I did not see any evidence of the lock slipping across the interface at all during hard cuts with the Blur.

Cutting cardboard boxes with liner locks always scares me because binding in the cut can make the lock fail miserably so I dawned my kevlar gloves for this test based on experience but the lock showed no signs of this weakness even when twisting it in hard cuts through corners and folded over edges and through double thickness parts of the box. I cut this stuff aggressively. So much so that the blade heated up from the cardboard friction. One time when I stopped to close the blade the lock stuck a bit, and then something I have never seen occurred. I guess in the twisting torque of the cuts I managed to almost move the torsion spring out of the hole in the blade because for a second it was no longer connected and had no spring tension or resistance on the blade. I thought for a second that I broke the spring already. Then from moving the blade it suddenly caught in the hole again and went back to normal to where I could once again feel the spring resistance when moving the blade to close it. Somehow it freed itself up there momentarily.


PM testing Saturday: For this the belly was used for the first time in testing.

Wood whittling:

The tip thrid is pretty dull at this writing, but I'll use it to compare to the factory edge as I continue. On hard woods forget it! The Blur is not set up for this. It slices it but it is not easy, and for the first time it was a tad uncomforable on a job when I tried push cutting it with precision two hand wood carving cutting techniques. None of the slices were very large or deep and after about 5 minutes of this I think my left thumb had had enough holding the edge to push cut the blade in attempts to whittle with it on hard wood. I used pecan wood for this and it was quite hard to make the thicker edge go through this stuff. I whipped it down to the sharper section of the blade to try that part of the edge in it since it was still factory fresh and sharp and although it was easier it is still obviously not the right profile for this type work.

On softer pine it sliced better of course. In both woods edge keeping, deflection of the edge and all was not an issue. What I did here didn't affect it but due to the thickness of the factory profile this type work is not this Blurs forte'. Doing much of this will wear out your thumb, hand and grip pretty quick without a reprofile of the edge. Hard push cutting in harder mediums like wood will require a thinner edge profile. I'm sure that is down the road.


For full blade length full force slicing cuts through the pine block taking off big slices was not a problem and the knife made short work of a 2x2 pine block 6" long. These were done standing up really leaning into the folder to force it through in sweep slices taking off as big a cut as I could muster bare handed. Once again after doing these cuts the lock stuck a little to close the knife. The spring release situation did not show its face again though after these hard cuts twisting out bigger flakes of wood with the blade. The knife does ok for this but its just the more controlled push cuts like you do for carving where the knife begins to show weakness and get uncomfortable. For most folks this is not an issue at all anyway since not everyone is a wood whittler. To make quick tent stakes in a pinch or make some bigger slices of dry wood to start a fire it is not a problem at all. The Blur can handle that fine, but you won't be carving any wooden faces on walking sticks with this one.

On the way into the house I used the blade to cut down five thick ragweed plants growing around my storm shelter that have been bothering the wife. Everyone of these plants was upwards of 7 feet tall or more from all the recent rain and had very thick fibrous stocks at the base. They were so well rooted in the ground that I could not pull them up with all my strength. The knife sailed through them with ease leaving clean cuts and no little strings.


Once in the house I washed up the blade and used it to slice up tomatoes in the kitchen for our salsa. One thing about lots of rain is that tomatoes love it. We have 150 tomatoes of various kinds here ready to eat or getting ripe in the windows and decided since we've given away all we can to neighbors to the point they don't want or need anymore that it was time to do something else with them. Salsa time in Oklahoma and the SG2 sliced and diced as well as any folder I've used in the kitchen. It made short work of a bunch of tomatoes, onions, as well as some pepprocini peppers and a skirt steak for our stir fry where it was used to slice the meat thin and remove excess fat before cooking it for dinner this evening.


Sunday testing continued:


I took the knife back to the shop after three light swipes on a ceramic to bring the edge back to a nice bite and to straighten out those deflected areas. That part of the blade I had done the most work with was quite bent over by now and it straightened right back up fairly easy. At this time the bite the blade has appears to be right up there as good as it was from the moment I opened up the box. This time I took it through 200 fairly effortless slices and cuts through the hemp testing more of the edge than just the tip third. The tip portion did not deflect as it did yesterday but instead looked fairly good all along the parts used to cut throughout which indicated to me that the initial deflection of some carbides was probably just getting rid of some flaking from heat treat maybe or from the newness factor. Its possible that one part of that old dirty rope I have had some crap in it that dinged the blade on the first few cuts also. Whatever the cause, the point is it didn't reoccur on the part I touched up with the ceramic during the second series of hemp rope cuts today, and although it seemed as sharp on the tip I don't think it was. Yesterdays cutting did dull it back some because today cutting with that tip third vs the belly and back third was slightly more effort to get through the hemp. Still it did well though.


On softer materials this knife push cuts as well as anything else I've used from Kershaw and cleanly cuts the hemp (when sharp) probably better than any other knife so far tested from Kershaw. I cut the full three strand hemp rope a couple of times with it this morning. Thats three strands of hemp, 1/2" thick each and it cut them as cleanly as I have ever seen any folder do in my tests. This was right after finishing the 200 half inch cuts and after giving it a touch up on my Lansky ceramic. I lopped off that rope like nothing I've seen since doing it with the big Dog Father chopper in a big chop and this was a controlled force down cut and slice all in one motion. Very impressive. This thing would cut a seat belt or rope bridge down in seconds flat even after all this use.


After some initial run throughs over the last three days I've come to the following conclusions:


I don't know the hardness of the SG2 blade but it seems damn hard to me. The edge holding on this test blade is as good as any knife I have ever tested or owned when cutting these materials. Its right up there in super knife category in my opinion for the blade steel and certainly seems to be neck and neck with ZDP189 and the super hard 13C26 Storm II and my Japanese White Steel and Blue steel wood carving knives for edge keeping. All of these above mentioned steels are 64 plus on the Rockwell hardness scale so I would have to conclude that the SG2 has to be up there also.

Stability of the edge seems superior to me over S30V especially, but I don't know that its quite as stable as 13C26. I know very little about this SG2 steel and have not read up on it but it seems to be what everyone had hoped S30V would be in regard to edge stability when it first came out. It seems to cut and keep its edge as tenaciously as ZDP189 to me but based on the touch up sharpening I'm inclinded to believe at this point that its eaiser to maintain and sharpen than ZDP is. I'll know more on that later. I wish I had a knife in ZDP steel around the same size and shape as this one to compare side by side with new fresh edges ready to go at the same profile and edge geometry. Two Blurs, one with ZDP, one with SG2 would be a good battle of the super steels.


In the rope and cardboard I found the SG2 to be a great push cutter as I said before, but not so much in the woods though and here both my ZDP Krein regrind and reprofiled Storm II kick its butt due to the thinner edge profiles and stropping and nothing else. One thing the Blur has over both these though is the better handle comfort. One of the reasons I love the JYDII is the comfort it provides the user but the JYDII can't keep up with this cutting performance done here using the SG2 blade. I would rate the Blur handle as just as nice for grip comfort as any knife to date that I've tested from Kershaw.

No staining or visible signs of any pitting by fruit or vegetable acid is apparent on the SG2 blade or the edge from the uses I put it through in the kitchen. I can't say that for the D2 or ZDP blades used in the kitchen over time. I thought that ZDP suffered noticably from the acid of tomatoes and oranges personally and every bit as bad as D2 did. I've also seen some rust form on ZDP. It will be interesting to see how this SG2 does there also.


The SG2 blade cleaned up with soap and water well, and didn't seem affected as much at the edge by cutting all the tomatoes, onions, peppers or the meat but I did think that cutting these things dulled the bite down some. The bite came right back with relative ease though when compared to ZDP189which has sometimes been very difficult for me to get that same bite back on. I can say that about some regular VG10 I've owned also.

Conclusion. This SG2 Blur is a winner for edge keeping, sharpening ease seems to be a plus also. Looks are top shelf, comfort in the hand in very tough jobs is an A +. It is a knife I'd recommend and what I would call an all around great performer.

I'd love to see a thicker lock in the Blur and a flipper also, more akin to the JYDII lock thickness and flipper that have spoiled me and I'd also like to see the traction grooves for grip to aid the thumb carried out a bit more on the blade for when its open. What is there is noticed and helpful but lacks enough grip to keep the thumb in place when you need them in harder cuts. Just my opinion of course.

Sorry for the length.

Thanks for reading.

STR

 

[jvan]

Thanks so much for the excellent detailed review, I always look forward to your reviews.

John

 

[nygiantsfan3342]

Great review, but we need pics!

 

[kneedeep]

Great review, thanks for taking the time to share the info!

 

[STR]

I believe you are right Kneep.

I've scratched the tar out of the blade. Sorry, but its been run through the testing phase here. Probably seen the abuse and use of a two and a half month old folder in two and half days and I'm afraid it shows.

STR

 

[kneedeep]

Considering what you described it's been through, it doesn't look too bad.

I can't wait to get one... just need to find one in stock somewhere.

That is still the factory grind on it, isn't it?

Do you think you'll try to re-profile it down the road a bit?

 

[PatriotDan]

Thanks for a very comprehensive review :thumbup:
(a summary at the very beginning would have been great because I'm a lazy dog)

I tried to search for SG2 and it's a laminate steel. Does anyone know the steels used in core and sides? What is the consensus on the use of this steel? Small utility cutters? Hunting knives? Bushcraft knives?


Edited to add: is the SG2 a Kershaw proprietary steel?

 

[STR]

Considering what you described it's been through, it doesn't look too bad.

I can't wait to get one... just need to find one in stock somewhere.

That is still the factory grind on it, isn't it?

Do you think you'll try to re-profile it down the road a bit?

Those pics were scanned about mid way through testing I just didn't think to post it earilier.

STR

 

[thombrogan]

is the SG2 a Kershaw proprietary steel?

No sir. It's made by Takefu Special Steel Company. It's usually found on high-end kitchen cutlery made in Japan (Shun's Elite and Kaji lines use it and well as Ryusen's Blazen, V-Metal, and V-Slim lines. I think Tojiro used to use it for some of their rarer sets, but they apparently value terse people to answer their emails) and will occasionally make itself shown in knives from Kershaw and Fallkniven.

STR,

Great review! Do you think it would be worth your time to take the 120 grit EdgePro stone to the edge and thin it down or keep it as is for a robust edge that rarely dulls?

You mentioned the detent ball in the lockup setup. Do you know if that would allow for safe use of the Blur (SG-2 or otherwise) should someone accidentally disassemble his Blur and tear out the assisted opening switch?

 

[jaislandboy]

thanx for the detailed review Steve.... :thumbup:

 

[STR]

No problem on the review. I enjoyed using it and being amazed by it.

Thom, yes to your question. When the spring broke on my Scallion there was nothing in the way of a prevention from the blade opening other than the lock which I never used anyway. A simple 1/16" carbide drill from Jantz supply was all it took to activate the detent ball by simply taking the blade out and marking the place right above the line the detent ball created on the blade from rotating it as it opened and closed. Once the spring came having the detent active did not inhibit the action at all.

It is probably Kershaw's view that the lock makes it unnecessary for the detent on those models which makes sense but to me those locks, good as they are take away the one hand operation which I can't live with personally.

STR

 

[offsetlover]

that was a great review STR. now i need to get this one! maybe i could get it for a late grad pressent from my buddy peter..........

 

[STR]

Oh boy. Just realized I skipped out on the reprofile question. Sorry Thom.

My bad there. I like the knife as is right at the moment but I do like being able to whittle and carve with my frequent use knives. Most of the Spydercos come ready to do that right out of the box and perhaps I've been somewhat spoiled there. I may yet take this one down but not sure yet how far. I'm thinking around the level you took the Storm II down to when you had it. We'll see. Right now its keeping its edge so well that I hate to mess with it further. I can always use another knife for my carving needs.

STR

 

[JSR]

Wow, that's some testing and review STR, thanks!

You seem to mention your StormII has better edge retention than your JYDII, is that correct?...or am I reading that wrong? If so, how is that so as both use 13C26?

Thanks.

 

[Thomas W]

JSR,
STR is referring to a 64 Rc Storm test piece that had been reprofiled (aaahhh...the BF memories with that knife, hopefully I can sleep tonight). The JYD II was a regular production version.


Ok I just showered off that past recollection, I think I'll be alright.

 

[allenC]

Great review!
I appeciate the time and effort you took too.

I think the Blur has one of the most comfortable handles ever!

 

[STR]

Yes my StormII is a very unique one that was never a production so I probably should stop mentioning it comparing it to other production folders. I just have found it to be a super knife and rate it very highly, both for how I feel about it in my own arsenal of carry knives and how it performs.

Thanks Thomas. And thanks for the comments. I think the SG2 blade steel is a real winner. The Blur handle is so nice in the hand too. I am really liking this knife a lot as of late.

I got a Boker Turbine sent to me a few weeks ago to look over and of course that one is in their version of the rust proof steel similar to H1. I had been carrying it pretty much religiously until this Blur arrived. Haven't even looked at that Boker since that Blur came.


STR