Small Sebenza : S30V

[Cliff Stamp]

The small Sebenza has a blade length of 2.94", made by stock removal out of 0.125" S30V stainless steel through hardened to 58/59 HRC with an overall length of 6.875" when opened. The handle maderial is 6Al4V Titanium.

This one weighs 80 g and the steel is 0.118" thick at maximum. The blade has a maximum width of 2.2 cm with a 1.75 cm high primary hollow grind which tapers to an edge ground at 0.012-0.014" thick and beveled at 14.6 +/- 0.9 degrees per side.

The primary hollow grind is very deep. At 1/8" back from the edge the blade is only 0.018" thick and even back another 1/8", 1/4" in total , the thifkness has only increased to 0.025, many utility folders like the Point Guard are this thick right at the very edge.

David Boye grinds his folders with thinner edges, he gets down to 0.005-0.010" but his hollow grinds are not as deep. Spyderco runs some high flat grinds on thin edges but not quite as thin as the profile on the Sebenza. A shot of this one alongside the Byrd Meadowlark :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_meadowlark.jpg

Stock testing :

New in box the small Sebenza could shave ok, but not perfectly smooth and could not catch hair above the skin. It could cut newsprint on a draw but not push cut it from a dead stop. On light thread it took 125 +/- 12 grams to make a cut, significantly sharper through the tip than near the choil. On light cotton the aggression was low, under 200 grams of tension the edge needed 0.68 +/- 0.04 cm to make a cut.

With the new in box edge the small Sebenza push cut 3/8" hemp with 22.5 +/- 1.0 lbs and had no aggression on a slice which correlates well to the cotton performance which also showed low slicing aggression. Whittling hardwoods, the Sebenaza did well able to make a one inch point on birch hardwood in 5.6 +/- 0.4 cuts, and 6.1 +/- 0.5 slices on basswood dowel.

The point on the small Sebenza is 0.725" wide with a 1.09" taper at 3.1 degrees. This sim and tapered design has high penetration ability which is readily illustrated by some phone book work. It achieves 229 +/- 4 pages with a 50 lbs push, and 664 +/- 26 pages with a hard vertical stab.

Food preperation :

The small Sebenza works very well as a fine paring knife. The cutting ability is high due to the thin and narrow edge and the deep primary grind. It peels potatos very well :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_potatoes.jpg

It cuts into the potato with light force and is also very comfortable in hand due to the edge being close to the grip so there are no leverage issues. The handle is well suited to the sideways grip normally used for paring and similar cutting :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_pinch.jpg

The point is also very fine and thin and easily able to do precision coring and remove small defects in potatoes and remove root stems. This is one of the better folding paring knives seen, it is in the same class as the U2 for general cutting and handling attributes.

The small Sebenza works well on soft vegetables, easily dicing up a green onion :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_green_onions.jpg

some carrots :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_carrots.jpg

and can dice up an onion easily, readily slicing through the onion sideways unlike some thicker knives which can't do this at all and have to stand the onion on its side to make the necessary cuts :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_oinions.jpg

It also works well slicing up small sections of meat, gliding easily through a section of beef heart :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_heart.jpg

In general though there are some problems in slicing up the thicker vegetables in regards to binding as the hollow grind tends to wedge excessively. On potatoes while the japanese utility from Lee Valley makes thin slices with about a pound of force applied the small Sebenza takes around five as it sticks badly.

On vegetables which tend to crack and open up a little more it does much better in comparison. On small to medium carrots where the japanese utility takes around three lbs, the small Sebenza is around five.

The small Sebenza is too small to work well on deep cuts of meat or thick slices of bread, just a limitation on blade length mainly. The profile would work well if it was a lot longer.

Grasses and light brush

The small Sebenza cuts light grasses well when sharp, however the very short blade really reduces efficiency. The performance can be raised by fashioning it into a small billhook by lashing it to a piece of wood which gives much greater reach. An example with a Meadowlark :

http://i7.photobucket.com/albums/y269/CliffStamp/Spyderco/Byrd/meadowlark_baton.jpg

The only concern here would be accidently hitting a rock which which is covered by the grasses as the very thin hollow grind on the Sebenza combined with the brittle nature of S30V would likely lead to gross blade failure.

woody vegetation :

The small Sebenza has little mass and thus can't chop effectively and like other small folders like the Meadowlark can cut down softer woods faster by slicing into them rather than attempting to chop. The slicing ability is very high as noted on the stock whittling work and the small Sebenza easily takes a piece of pine and converts it into a pile of shavings for tinder :


http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_shavings.jpg



Lock :

The small Sebenza has an integral lock, which is essentially a verson of the Walker liner lock which uses one of the handle slabs for the liner, hence the lock is integral to the handle.

The lockup was stable under light to moderate spine whacks which readily dented clear pine. White knuckling was not a problem outside of grips which ran the handle straigt across the second joint of the index finger which would allow the lock to be released readily in a tight grip.

Handle :

In a hammer grip, the handle "hot spots" readily, mainly due to the squarish nature of the clip. While the spine of the blade is well rounded, the clip is not and thus presents a high pressure point profile :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_hammer.jpg

In reverse grip there are similar issues, plus the apex of the transition between the grind of the handle along the top where it forms the triangle at the front is rather sharp. A complete smooth arc would be more ergonomic in general :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_reverse.jpg

A choked up grip with thumb on the spine really shows the use of the fully rounded spine as the comfort is high:

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_thumb.jpg

The handle slabs in general could be more rounded like the blade spine, however they are at least broken on the inside of the slabs and many folders leave that area almost perfectly squarish such as the Byrd Meadowlark, where as on the small Sebenza it is beveled just like the outside.

A lot more work is planned, edge retention comparisons against other S30V knives, as well as other steels, much more cutting both regular EDC as well as a lot of wood work.

-Cliff

 

[GarageBoy]

Can't wait for the conclusions!

 

[thombrogan]

Great preview of the small Sebenza. Luckily for my wallet, the pictures don't match those of LawrenceM's. Very glad to read that a high-end knife is designed with high-end cutting ability.

Two asinine asides:

1. Isn't there a hell for people who photograph the CRK knives together with knives made in Chinese factories?*

2. How does flick?

*= I think it's "The Hell Where People Who EDC William Henry and $3 Sheffield Lockbacks Are Sent."

 

[Cliff Stamp]

Very glad to read that a high-end knife is designed with high-end cutting ability.

Maybe I got lucky for once and got one that was ground thinner than normal, but given the tight tolerances Reeve is known for, aside from the slight random difference you could assume from the edge finishing I would assume this is pretty standard.

This is one of the thinnest hollow grinds I have seen, it is deeper than Dozier's K2 significantly, and almost to the point where Alvin might not call it an axe if you could get him to forget about it being stainless long enough to actually look at it, and not tell him it is only 58/59 HRC.

Isn't there a hell for people who photograph the CRK knives together with knives made in Chinese factories?

Yes, it is the hell of being cut to pieces.

How does flick?

You had to know as soon as I opened it I went for the flick, not a chance you might as well try to flick open a SAK. I don't even think Jim March could budge this one.

-Cliff

 

[mete]

CRK states that the Sebenza is NOT designed for 'flicking' and doesn't recommend it !

 

[thombrogan]

True, Robert, but the BFC Forumite known as "Scott Dog" agreed to cover any flicking-related damage Cliff might cause.

Cliff,

Now your description is becoming as painful as the other pics. Hopefully, you won't be reviewing a Mnandi.

 

[Cliff Stamp]

CRK states that the Sebenza is NOT designed for 'flicking' and doesn't recommend it !

What! Someone should have told me, I would never do anything with a knife if it was not designed to do it.

Hopefully, you won't be reviewing a Mnandi.

No, I don't know how to pronounce that so if someone asked me what I was carrying I would obviously be forced to deanimate them.

The Sebenza tends to grow on you, well it grows on me anyway, but when any knife cuts well I start to ignore almost everything else, or at the very least it starts to become really less important. Until you use another knife which cuts as well or better anyway and doesn't have the drawbacks.

It does work really nice as an EDC. It has the same blade length as the Paramilitary but take both out in a store to cut on an apple and watch what happens. Or even have someone just ask you what each is called, "Sebenza" doesn't freak most people, especially if you precurse it with small/baby. Maybe I should start calling the para the baby military.

The biggest difference between the two knives is the size of the handles. Not only is the paramilitarie's longer directly, but because it integrates smoothly with the choil which forms a natural extension of the handle, the effective grip length is about 30% longer than the small sebenza. This makes the grip dynamics very different even though the blade lengths are near identical.

As for the lock, I have refered to in the past the problems of integrals with torques and impacts and after using this one for a few days it is apparent why people tend to not get this issue with the Sebenza as with this blade profile you can't really actually stress the blade in that manner as the edge is way too thin, you twist this in a piece of wood and you could leave a large piece of the blade behind.

Which bring up the whole heavy/hard use label, this is really out of place on this knife, the blade profile is designed purely as a low stress cutting knife which is not intended to handle even light/moderate lateral stress. Great knife for some work, but that label is just really out of place. It would be like calling something like the Fulcrum a great paring knife.

I like the blade finish on the Sebenza though, its like getting a pre-scratched up knife, though I would wonder about the corrosion compared to a hard ceramic bead blast. The handle finish is kind of interesting, as a user it has a decent grip feel, but for those constantly raving about the fit and finish it makes little sense as with just a few days carry it has huge scratches.

It would also be nice to have the blade labeled with S30V, when you have different steels it would be nice for the user to be able to tell them apart on the secondary market. I also meant to note that the lock engagement is way over half way, I like this as the whole "break in" arguement I find insensible.

-Cliff

 

[OwenM]

It does work really nice as an EDC. It has the same blade length as the Paramilitary

Those are the two knives that I carry almost exclusively right now. The small Sebenza away from work, and the Paramilitary on the job because it's easier to get out quick, and with gloves on, and the handles are more secure with wet or muddy hands/gloves.
I've long wondered about the statements about the Sebenza's lock security, and was going to suggest that you leave that for last in your testing, because the blade may very well break before the lock gives.
The large and two small Sebenzas I've owned were all BG-42, so I'm curious as to how well the S30V does compared to Spydercos in edgeholding since it's apparently a point or two softer. I don't think it will make a huge difference, though I think ease of sharpening and rolling vs. chipping with a slightly softer steel decreases maintenance time, and could indeed be considered "better" edgeholding depending on perspective and actual use.
I've cut through some large containers at work with my first small Sebenza that were very thick, and had me using one hand on the knife, the other hand over it, and my full body weight forcing the blade into the cut without damage, even though there was considerable torque involved, too, so even though it's ground thin, durability has not been an issue with anything that I would normally use the knife for.
Nice to see the details on the light work, which is where the knife truly excels, IMO.

 

[DaveH]

Bridget mailed me back to say that the first 300 hundred S30V blades were not marked and on some of the later others the S marking is very faint.

I'd say is if had a born date at or around the switchover (whenever that was) it might be hard to say.

 

[Cliff Stamp]

[paramilitary]

...it's easier to get out quick, and with gloves on, and the handles are more secure with wet or muddy hands/gloves.

Yeah, exactly how I see it. It is also nice for heavy cutting to not have the handle inside your hand because if it is then the end will form a high pressure point. This was a problem I had with mini knives from Griffith.

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_sabre.jpg

vs
http://i7.photobucket.com/albums/y269/CliffStamp/Spyderco/paramilitary/paramilitary_sabre.jpg

I'm curious as to how well the S30V does compared to Spydercos in edgeholding ...

Yeah, sharpening will be interesting as well, any difference in ease of machining as well as burr formation. I am also going to have Wilson rehardening something and compare that as well.

....though it's ground thin, durability has not been an issue with anything that I would normally use the knife for.

Yeah I don't think most cutting would be a problem, unless you get an accidental twist. You can do a lot of work with it no problem, for example :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_joint.jpg

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_flippers.jpg

That is a bunch of joint seperation on seal flippers. Cut around the meat, reverse the blade so the spine is down and use the point to pop the seal on the joint and cut away the tissue.

My point about the heavy duty comment was mainly one of general utility, compare the profile in terms of robustness to something like the para which isn't a pry bar by any means but is many times over more durable.

This of course isn't a bad thing, Alvin's knives are not even as durable as the Sebenza, they are thinner still, so likely is the U2 that Krein modified. Just look at the knives it generally gets compared to with the "hard use" label.

I'd say is if had a born date at or around the switchover (whenever that was) it might be hard to say.

This one was this year. March 2005.

-Cliff

 

[Cliff Stamp]

As a followup to what I meant about heavy duty, cutting isn't really a problem, even fairly heavy cutting. This is a bunch of pop bottles cut in half including right through the bottom.

It takes ~45 lbs to cut through the small ones, on the one and two litres it takes 75 lbs and I needed a glove as the handle on the small sebenza was really high pressure pointing.

I did a couple of cuts with the K2 and interestingly there was no significant force difference. The K2 has a thicker hollow primary profile, but the edge is more acute, so it tends to balance out.

The grip on the K2 is much mor ergonomic though, no glove necessary :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_k2_plastic.jpg

The small Sebenza was then used to cut through a pepsi can, no effect, opened a large apple juice can, the edge was visibly reflecting light, chipping was small, ~0.1 mm deep :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_tin_open.jpg

I then cut a piece right out the side of the can, this takes a fair amount of force, about 20 lbs, much more than opening the top. It also is really difficult to cut well because the can is ridged and it is very easy to twist the blade so you really have to watch yourself here. :

http://i7.photobucket.com/albums/y269/CliffStamp/reeve/small%20sebenza/sebenza_apple_tin.jpg

This broke a small piece of the tip, just a fraction of a mm, the edge was chipped out in several places, 0.2-0.3 mm deep.

Sharpening revealed a major problem, while the primary edge grind is decently acute, however there is a fairly obtuse secondary edge bevel at 20+ degrees. The Sharpmake just hits the shoulder. Being curious I reprofiled one side to 20 on the medium rods (corners).

I was going to cut it down to 15 but decided to first do a quick run to even up the bevels at 20. 1050 passes passes later one side of the edge was at 20 degrees. I then recut the other side with an x-coarse DMT hone with 150 passes.

I don't think I'll bring it down to 15 on the Sharpmaker, x-coarse waterstone will cut it down to 10 shortly.

-Cliff

 

[Nordic Viking]

This broke a small piece of the tip, just a fraction of a mm, the edge was chipped out in several places, 0.2-0.3 mm deep.

Sharpening revealed a major problem, while the primary edge grind is decently acute, however there is a fairly obtuse secondary edge bevel at 20+ degrees. The Sharpmake just hits the shoulder. Being curious I reprofiled one side to 20 on the medium rods (corners).

How about posting a pic of the chipped tip if you can? (I'm curious to see how it looks like.)

 

[Cliff Stamp]

You would need a far better zoom than I have to show a defects which are a fraction of a mm in scope.

-Cliff

 

[Nordic Viking]

You would need a far better zoom than I have to show a defects which are a fraction of a mm in scope.

-Cliff

LOL, my bad - didn't see the . before the 2mm. You should get a better camera though

 

[OwenM]

This one weighs 80 g and the steel is 0.118" thick at maximum. The blade has a maximum width of 2.2 cm with a 1.75 cm high primary hollow grind which tapers to an edge ground at 0.012-0.014" thick and beveled at 14.6 +/- 0.9 degrees per side.

The primary hollow grind is very deep. At 1/8" back from the edge the blade is only 0.018" thick and even back another 1/8", 1/4" in total , the thifkness has only increased to 0.025, many utility folders like the Point Guard are this thick right at the very edge.

Rereading this, those measurements struck me as being rather small.
My BG-42 small Sebenza measures .121" at the top of the grind all the way out to where it tapers toward the tip.
The edge bevel is .019-.021" at the top, and 1/4" behind the edge the blade measures .034-.035".
I know the blades are hand ground and there will be some slight variation, but that strikes me as more than "slight". Wonder if they're intentionally grinding the S30V ones thinner?
Or yours is ground thin, mine is ground thick-who knows?
Anybody want to put the calipers to their small Sebenzas just to see?

 

[Cliff Stamp]

I was wondering the same thing Owen so I asked in the main forum and also asked Reeve directly. Reeve noted the edges are spec'ed at 0.020 and 0.023" for the small/large Sebenza. However I am not the only one with a really thin under grind :

http://www.bladeforums.com/forums/showpost.php?p=3126353&postcount=18

Yes, that seems like a large difference to me as well, you are looking at double the thickness which will obviously have a large influence in scope of work. I like this grind on the small and would constrain it to ligher work, but on a large I would prefer something a bit heavier to allow harder wood work.

Differences this large would obviously allow for hugely different perspectives on the cutting ability and durability of the knives. You could mic the edge as fast as you could give the knives a "birthday card" unless it is unreasonable to expect a lower variance in hollow grinding.

-Cliff

 

[DaveH]

Just curious, how do you position the mic to get that reading, it it right where the sharpened edge tarnsitions into the blade proper?

Heh, I can see it now. Bunches of sebenzas arriving at the shop, "Please make mine .012 or less please"

 

[Cliff Stamp]

Just curious, how do you position the mic to get that reading, it it right where the sharpened edge tarnsitions into the blade proper

Yeah, it gets difficult on blades where the point is buffed heavily, Hossom for example does this so there is no crisp distinction. On them the best you can do is measure a specific distance from the edge and note that.

You should get a better camera though

Yeah, it is always camera or knife, knife usually wins.

-Cliff

 

[Ebbtide]

Yeah, it gets difficult on blades where the point is buffed heavily, Hossom for example does this so there is no crisp distinction.

And all this time I thought Mr. Hossom used a hollow grind with a Moran/slack belt/convex/appleseed edge.

Not the beveled edge found on the CRK.

sigh.

 

[Cliff Stamp]

And all this time I thought Mr. Hossom used a hollow grind with a Moran/slack belt/convex/appleseed edge.

Reeve actually does the same, primary hollow with edge convex, belt edge hit with a buffing wheel. You can't notice the curvature as the edges are so thin.

In the above I was talking about the transition from the primary to edge grind, on some knives this is buffed and thus it can't be easily pin pointed, Hossom is one maker who does it.

It isn't even relevant to the question Dave asked as to the nature of the primary/edge grind. Hossom has even done sabre flat grinds on some of his knives and I assume he still buffs the transition line.

Busse does it as well on their satin finished convex blades so you can't see a distinct primary/secondary edge grind.


-Cliff