Simple question about blade terminology (primary, secondary bezel, grind)

[the kid]

I thought I understood primary and secondary bezel but after reading Wikipedia and some sharpening threads with pictures here I'm not so sure.

I made a picture to show what I think is the right terminology:

The blue (primary bezel) is the sharp part of the knife and when you sharpen (or re-profile) an edge this is what you are actually altering.
The red (secondary bezel) is not necessary but could help with keeping an sharp edge longer.

Assuming this is correct how does this relate to the Wikipedia page?

For example.
A convex edge is when the blue (and red) part (aka the edge) is rounded. Basically you have a primary and secondary bezel in one round edge.

But if I look at the Wikipedia page where they call it a convex grind it seems the convex starts at the second black arrow in my picture.

Can I assume a convex edge is not the same as a convex grind? aka the pictures on that Wikipedia page do not zoom in on the edges but only show the two black arrows in my picture?


I apologize for the bad writing but English is not my main language and I'm having difficulty when I have to explain technical stuff.

EDIT.
I made another picture based on the feedback.

 

[Scurvy092]

Top question mark is the 'flat'

Bottom question mark is the primary grind/bevel.

What you have listed as the primary bevel is the secondary bevel and on the majority of knives it just goes straight to the edge.

What you have listed as the secondary bevel is not very common and would normally be called a micro bevel.

 

[daizee]

'bevel', not 'bezel'

http://en.wikipedia.org/wiki/Bezel

North American terminology is consistent with Scurvy's description. Your picture has one more bevel than is typical. Apparently Japanese terminology swaps primary and secondary (primary being the one that cuts in that case).

 

[the kid]

Top question mark is the 'flat'

Bottom question mark is the primary grind/bevel.

What you have listed as the primary bevel is the secondary bevel and on the majority of knives it just goes straight to the edge.

What you have listed as the secondary bevel is not very common and would normally be called a micro bevel.

Ah! But now I'm really confused.

I've read a secondary bezel is not standard procedure but in fact all my knives from the factory come with a secondary bezel. A lot of pocketknives don't even have a flat. So this means if I don't want a secondary bezel I sharpen the whole blade from top to bottom?!

 

[Scurvy092]

Ah! But now I'm really confused.

I've read a secondary bezel is not standard procedure but in fact all my knives from the factory come with a secondary bezel. A lot of pocketknives don't even have a flat. So this means if I don't want a secondary bezel I sharpen the whole blade from top to bottom?!

A blade with no flat and no secondary bevel is called a Scandi grind.

 

[the kid]

Is it safe to say in general pocket knives come with a secondary beVel and fixed blades don't?


This is really odd, like finding out the earth is flat after all.

I wont be able to post for a few days but will update the thread with more pictures and more questions off course.

I think I will have a lot more fun (free hand) sharpening with this information. Thanks guys.:thumbup:

 

[G. Scott H.]

There isn't 100% agreement on terminology. I learned it like the pic below, but some use the exact opposite terms, calling the small edge bevel the primary and the larger bevel above it the secondary.

edit: Also, what you have marked as the "secondary" bevel in your pic is what I would call a "microbevel." Does that add to the confusion?

edit 2: I think of the first bevel that is ground into the knife as the "primary" and the second, smaller bevel ground at the very edge as the "secondary." I think this is why this terminology appeals to me more than the opposite. I believe the reasoning behind the opposite terminology is that the edge that actually initiates the cut should be considered the "primary," while the bevel behind it that simply continues the cut (by spreading the material being cut) should be called the "secondary." I guess it depends upon how you look at it. I still prefer the terms as used in the pic I posted, and I think these terms are more commonly accepted.

 

[daizee]

Ah! But now I'm really confused.

I've read a secondary bezel is not standard procedure but in fact all my knives from the factory come with a secondary bezel. A lot of pocketknives don't even have a flat. So this means if I don't want a secondary bezel I sharpen the whole blade from top to bottom?!

The single-bevel design is often called a 'Scandinavian grind', which may be common where you are from. It is much less common in the USA. Here in the USA, most pocket knives have a flat or hollow ground primary bevel as in GHScott's post, with a secondary 'V' edge bevel. Many fixed blades sold as 'bushcraft' knives in our market (again, USA) have the single-bevel (not 'bezel') scandinavian-style grind.

-Daizee

 

[Smokinape]

Best thread ever! There is alot of term confusion...

 

[the kid]

I'm back from my short trip to Germany

I made another picture and updated the original post. I hope I got it right this time.

Also I took a picture from my unsharpened Condor fixed blade and my Case Sodbuster because I think it shows the differences.
The case does not have a flat. The condor does not have a secondary bevel.
This is correct, right?

I still have a few questions though.
If I want to sharpen the condor I remove material from the primary bevel, aka the whole not coated shiny bit in the picture?

The Wikipedia page does not mention secondary bevels. I can put a convex secondary bevel on a flat grind? Or a flat secondary bevel on a hollow grind? What is considered "normal" for secondary bevels? I notice some of my pocket knives have a hollow grind but a flat secondary bevel.

And as a bonus question out of curiosity: How does one sharpen a hollow grind without a secondary bevel