Different grinds

[L2bravo]

There seems to be a couple of threads going right now, that are close, but not exact to what I am in question about.

I recently bought a Sharpmaker. I have also bought the extra diamond stones, and the extra fine as well.
I have always been into knives somewhat, but am way deep now (read OCD).

I have a Spyderco Salt 1, and a hollow grind Endura in question here. Here is what I did sharpening these knives.

Salt 1:
30 degree - medium, fine, extra fine stones.

40 degree - light micro bevel, medium, fine, extra fine stones.

The edge is mirror polished, and cuts like a razor. No complaints.

Endura:
30 degree - diamond stones, which put a hell of a coarse grind on it. I then followed with a little work on the fine stones.
There are still very light grind marks present. This knife too will shave, push cut phone book paper, etc. But, cutting cardboard and such, this thing cuts like a banshee!

What is going on here? How can I use such different techniques, get similar sharpness results, but the performance is so widely ranging?

Somebody smarter than me, please explain the mechanics of this. Also, would I be well served, by coming back with something like the extra fine stones, and putting a 40 degree micro bevel on the Endura?

Thanks for the insight guys!

 

[9blades]

First off, Could you please expand on how the performance differs between the two?

 

[L2bravo]

Sorry 9blades. When I say they're different, they are very different. Say for instance, when cutting cardboard, the Salt1, cuts like you would think a "normally" sharp knife would. When using the Endura, it cuts a lot more "aggressively", I would say. Its like they are not even close to being in the same ballpark.

I'm sorry, I am trying to better explain, but there isnt an easy way to do so. They both shave very easily. They both push cut phone book paper with ease. They both are sharp as hell. But when you are cutting something of any real significance, they are different.

 

[Obsessed with Edges]

There seems to be a couple of threads going right now, that are close, but not exact to what I am in question about.

I recently bought a Sharpmaker. I have also bought the extra diamond stones, and the extra fine as well.
I have always been into knives somewhat, but am way deep now (read OCD).

I have a Spyderco Salt 1, and a hollow grind Endura in question here. Here is what I did sharpening these knives.

Salt 1:
30 degree - medium, fine, extra fine stones.

40 degree - light micro bevel, medium, fine, extra fine stones.

The edge is mirror polished, and cuts like a razor. No complaints.

Endura:
30 degree - diamond stones, which put a hell of a coarse grind on it. I then followed with a little work on the fine stones.
There are still very light grind marks present. This knife too will shave, push cut phone book paper, etc. But, cutting cardboard and such, this thing cuts like a banshee!

What is going on here? How can I use such different techniques, get similar sharpness results, but the performance is so widely ranging?

Somebody smarter than me, please explain the mechanics of this. Also, would I be well served, by coming back with something like the extra fine stones, and putting a 40 degree micro bevel on the Endura?

Thanks for the insight guys!

Sorry 9blades. When I say they're different, they are very different. Say for instance, when cutting cardboard, the Salt1, cuts like you would think a "normally" sharp knife would. When using the Endura, it cuts a lot more "aggressively", I would say. Its like they are not even close to being in the same ballpark.

I'm sorry, I am trying to better explain, but there isnt an easy way to do so. They both shave very easily. They both push cut phone book paper with ease. They both are sharp as hell. But when you are cutting something of any real significance, they are different.

There was another thread recently, in which another member did something quite similar to the bolded part in your description quoted above (see quoted post below for comparison). Also very similar results in cutting. A rather low-grit, coarse & toothy edge applied first, followed by some polishing done with a higher grit ceramic. In effect, the low-grit 'teeth' add bite in draw-cutting coarse material (cardboard), and the light polishing smooths the segments of bevel between the low-grit grooves. Sort of like a polished saw blade, in that it has a lot of aggressive bite and the slicker bevels reduce friction. I think this may be why you're seeing it cut with greater ease in the cardboard.

Interesting stuff guys.*




This edge here:

Is on my Contego. I used a 120 grit SiC, followed by a 1200 grit ceramic.*
It's one of the most aggressive, slicers I've ever produced. You can easily see a reflection in the edge, but clearly there are also some left over grooves in the finish. What's going on with this that is making it so much better than other knives that have the same geometry?

David

 

[9blades]

Sorry 9blades. When I say they're different, they are very different. Say for instance, when cutting cardboard, the Salt1, cuts like you would think a "normally" sharp knife would. When using the Endura, it cuts a lot more "aggressively", I would say. Its like they are not even close to being in the same ballpark.

I'm sorry, I am trying to better explain, but there isnt an easy way to do so. They both shave very easily. They both push cut phone book paper with ease. They both are sharp as hell. But when you are cutting something of any real significance, they are different.

No need to apologize. David probably explained it better than I could haha!

 

[L2bravo]

This makes a lot of sense. This seems to be a pretty unique way bring out an edge that is toothy. Hell, I'm thinking about sharpening all my knives this way! Whats not to like??? Thanks for the help guys. Thats twice today......

 

[Obsessed with Edges]

This makes a lot of sense. This seems to be a pretty unique way bring out an edge that is toothy. Hell, I'm thinking about sharpening all my knives this way! Whats not to like??? Thanks for the help guys. Thats twice today......

Sort of has me curious as well. Found it interesting that you seem to see similar results with the same method posted in the earlier thread. I seem to vaguely recall some expression about one occurrance is just chance, two are a coincidence, and three are a trend (or a pattern, or something like that). Might have to try it myself.


David

 

[BluntCut MetalWorks]

Hollow grind or FFG Endura, please clarify? Either way, the saber grind Salt1 probably wedge cardboard more than Endura. Plus Endura blade has distal tapering. So both of these geometry variables favor the Endura over Salt1.

 

[L2bravo]

Hollow grind or FFG Endura, please clarify? Either way, the saber grind Salt1 probably wedge cardboard more than Endura. Plus Endura blade has distal tapering. So both of these geometry variables favor the Endura over Salt1.

Itls a Hollow grind Endura. So both knives are the same grind. Good point though. I could see a FFG being much better at slicing, but that isn't in play here though.