Convex edges are not stronger than v edge

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PlumasDePan

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Hi sorry to everyone that reads this post... i was confused about something but got corrected...

Please if mod, remove the post
 
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That is the whole point of a convex edge: to get better cutting with a V-edge, you to go to a smaller angle, and thus a weaker edge, than a convex edge.
 
Your construction is unrealistic.
In your first figure you drew the flat grind outside of the convex, but could have drawn it inside, meeting only at the edge and the spine.
Beginning the grind, in practice you have a fixed thickness of stock. You start by flat grinding. At some stage you make a choice. You can convex to a zero edge, or continue flat grinding until close to zero, but then usually put in a secondary bevel, which you didn't consider.
 
PlumasDePan said:
Which having into account that the edge is the weakest part of a knife. It means a convex will be almost identically strong as the V edge while having better edge retention and being a better cutter because of the smooth transition and the less amount of steel.
Click to expand...

So you get better performance from a knife with less steel, if that knife is convex ground? Sounds like that knife is stronger.

It's hard to tell, because you never really define "Strong"
 
Take your first graph and zoom all the way in, centered on the origin of the Cartesian plane. It will make sense then.
 
I was going to say.....nah forget it,you can believe whatever you want
 
PlumasDePan said:
A popular thing that i have heard a lot is that convex edges are stronger than a normal V edge.


Here we have someone from bark river saying that

Here there is a youtube video with over 100.000 views where we also have this

And if i do more searching i will find tons of more people saying the same thing.

Now that doesn't make any sense from a geometry standpoint

Here is what would be the half of a 27 degrees edge
BZTHFeE.png


As we see the tangent also has the same angle 27 degrees.... The red line is the equivalent of that covex in a totally flat V edge

However in all the draw there is no point where the convex is thicker than the V edge so there is no way the context has more material to support the edge

Now what I think is great about the convex is that the more closeto the spine of the knife we go the closest the angle tends to 0
MxAF87e.png

QYaUqWN


So if we calculate the area. The closest we are to the apex the close the two areas are to be the same so comparatively the convex edge has almost about the same material as the V edge close to the edge.

If we compare the Convex edge and the V edge after the 14 inch the distance between the point "I" and the point is "L" is almost the same as the distance to the center of the knife




Which having into account that the edge is the weakest part of a knife. It means a convex will be almost identically strong as the V edge while having better edge retention and being a better cutter because of the smooth transition and the less amount of steel.
Click to expand...
You have chosen to draw a convex grind that is thinner at every point than the V grind you have chosen to draw, thus demonstrating the possibility that one convex grind could be weaker than one V grind at all points. However, that is not how people in the real world do convex grinds and V grinds.
 
A Hamaguri grind is full height convex, as opposed to a convex grind which is in relation to the edge.


I just wanted to type Hamaguri.


Also, the OP would only be correct if the flat grind was at an incredibly high angle, which is not great for knives.
 
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