What is it?

Never really noticed it before this thread, you learn something new every day. Maybe that's one of the shuttle things about the knife that makes it so great. It's so comfortable in the hand, almost like an extension of the hand. So, I would guess it about ergonomics. Just like the top of the knife has an ever so slight arc, that has been mentioned. Subtleness that makes it a sebenza
 
Are you thinking that I meant rectify, as in fix? Like, grind the shape of the pommel in order to rectify the shape? :D

Because I most certainly did not. I intended to use rectify as in coming to terms with mentally or making sense...

I meant "make sense of".

And the more I think about it, it's a pretty silly idea to try. I think a design can and should incorporate a bit of artistic impression, and it is a little arrogant to think it needs to be explained, rationalized or defended, but that is just my current thought.
 
I think you would be surprised at how different the knife would look if that "little bit of pointless nothingness" wasn't there....but what do I know ? :)

I agree with Haze. The more I look at it the more I realize how the knife would be different without it. Assuming the machine that cuts this can only move in a true arc, and cannot transition during the cut (IE cut a parabola), the arc would have to be a bigger radius to meet the lockbar access cutout and keep the existing handle thickness. That would make the knife flatter on the bottom, due to the bigger arc, and you might lose a bit of that nice curve towards the but-end. The other option would be to keep the arc the same radius, but reposition it to have it cut further into the handle before swinging around to the lockbar access cut out. This would make for a thinner handle, and change the look.

I think what we are seeing is a compromise in design to achieve the great proportion and ergos of the 21, based on what CRK's technology could do at the time the 21 was introduced. The latest machinery could likely do something more seemless and fancy, but if it ain't broke.........
 
I agree with Haze. The more I look at it the more I realize how the knife would be different without it. Assuming the machine that cuts this can only move in a true arc, and cannot transition during the cut (IE cut a parabola), the arc would have to be a bigger radius to meet the lockbar access cutout and keep the existing handle thickness. That would make the knife flatter on the bottom, due to the bigger arc, and you might lose a bit of that nice curve towards the but-end. The other option would be to keep the arc the same radius, but reposition it to have it cut further into the handle before swinging around to the lockbar access cut out. This would make for a thinner handle, and change the look.

I think what we are seeing is a compromise in design to achieve the great proportion and ergos of the 21, based on what CRK's technology could do at the time the 21 was introduced. The latest machinery could likely do something more seemless and fancy, but if it ain't broke.........

There is no such limitation on any CNC that I am aware of..Where there is a limitation from my experience is XZ and YZ arcs with very large diameters..but those limitations don't exist on the machines that CRK uses..Just on the ones I use now and then.. :mad:

Here is a video to try and resolve some of myths about CNC's being the issue..Just assume that 3 axis machines have the same limitations as this 5 axis machine...very few beside an imagination.

Watch this..

[video=youtube;KDPA06D1r_8]https://www.youtube.com/watch?v=KDPA06D1r_8[/video]
 
Yes it does - checked my 21 with CF scale.
Wasn't really aware of it, but it feels good.
My guess is it's there on purpose.
Thank You for adding another aspect to my Sebenza.
red mag
 
There is no such limitation on any CNC that I am aware of..Where there is a limitation from my experience is XZ and YZ arcs with very large diameters..but those limitations don't exist on the machines that CRK uses..Just on the ones I use now and then.. :mad:

Here is a video to try and resolve some of myths about CNC's being the issue..Just assume that 3 axis machines have the same limitations as this 5 axis machine...very few beside an imagination.

Watch this..

[video=youtube;KDPA06D1r_8]https://www.youtube.com/watch?v=KDPA06D1r_8[/video]

Cool stuff Hyde. I guess what I was putting forth is that maybe when the 21 was first designed, CRK had limitations in the machine they had. If you look at the knife, all the primary, basic cuts, are simple arcs or straight. The bevel/chamfer is more intricate with the details around the screw-heads etc, so maybe they had two machines involved. I still think there is possibly a manufacturing argument for 'the hump' that may no longer be valid, but carries on as part of the design. Who knows? Let the mystery be I suppose.
 
Perhaps it is there to follow the natural curve one's hand makes when curling your fingers as you would when grasping a knife.

Hold your hand palm up, then watch what happens when your curl your fingers around towards your palm. It is not straight, it bends a slight amount.

So his knife handle design follows what is already naturally occurring. That's what I think is happening here.
 
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You may well be right Cody...I will sometimes design a flat on parts intentionally to have a feature that is orthogonal to ease manufacturability for something to locate on for additional operations..The Sebenza has these features built-in with the holes in the scales...But it's plausible.

Glad you liked the vid..It's hard for most people to understand why machining is so expensive..When you look around your house, you cannot easily find something that doesn't have it's roots in a machined part in one form or another. It's truly an amazing time to be living in :)
 
You may well be right Cody...I will sometimes design a flat on parts intentionally to have a feature that is orthogonal to ease manufacturability for something to locate on for additional operations..The Sebenza has these features built-in with the holes in the scales...But it's plausible.

Glad you liked the vid..It's hard for most people to understand why machining is so expensive..When you look around your house, you cannot easily find something that doesn't have it's roots in a machined part in one form or another. It's truly an amazing time to be living in :)

Thanks for the Vid, Mr. bhyde! Nice.

My own interpretation to OP's question - it enhances my grip and I leave it at that. :thumbup:
 
I guess I agree with Somber that is is hard to easily explain away, and don't think he's totally nuts to ask the question. The "hump" is too dicreet to really be an aesthetic feature, at least in my opinion, but I can offer no more ideas than have already been put forward. Here is the thread where is was previously, and tirelessly dissected: http://www.bladeforums.com/forums/showthread.php/1234817-Start-of-Mod-on-large-Insingo

Interestingly, the Micarta inlay is cut to match the "hump", so everything is quite deliberate, or simply necessary, when it comes to this detail (maybe this shows up in my picture?). Maybe Chris just put it there to give the real CRK devotees something to discuss! :D

DSCF3953_zps625e8401.jpg

Great photo Cody!
 
I noticed that little hump on my small 21 a couple years ago, but never thought much of it. Interestingly enough, it is also found on my small "P" Sebenza.
 
That's weird! Even my carbon fiber sebenza 21 has this bump. You can't see it with your eye, but you can feel it with your finger.
 
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