Finishing Grit For Face (Primary Bevel) Grinds?

[Karl H]

I am looking to start grinding down the primary bevels of my knives that have high flat primary bevels and a secondary edge bevel.

While there is quite a bit of information on the benefits of different finishing grits for edge grinds, I haven't found much information on preferred finishing grits for face or primary bevel grinds.

Is there any noticeable increase in performance associated with finishing a face grind with a finer grit than 100-250? Or is it merely a cosmetic consideration?

For the sake of focused discussion, lets consider applications like push cuts through wood, cheese, or any other high friction materials that might stick to the face grind increasing the energy required to complete the cut.

 

[sickpuppy1]

I see a lot of knives finished to 6-800 grit. I imagine it’s it’s too smooth you’d get sticking issues

 

[bgentry]

I see a lot of knives finished to 6-800 grit. I imagine it’s it’s too smooth you’d get sticking issues

That's a really interesting thought. Counter-intuitive. Rough or "bumpy" surfaces won't stick to things because they are composed of lots of high and low spots. So there's limited level area to stick to something. But highly polished flat metal is the opposite: Less bumps, more flat consistent area. Perfect for sticking to things.

I guess if you wanted a polished surface you'd want some kind of texture or wave or bump to it to minimize sticking. Interesting....

Brian.

 

[Karl H]

I should also mention that I plan on doing this for both stainless steels (S30V) and low chromium tool steels (3V and REX 45).

So, corrosion is a concern. However, these materials are also relatively wear resistant. So, it would also require a lot of time and grinding materials to get a fine polished or mirror finish.

 

[Mr.Wizard]

I guess if you wanted a polished surface you'd want some kind of texture or wave or bump to it to minimize sticking. Interesting....

That's how the polished hammered finish on Shun Premier knives is marketed. I haven't used one myself.

 

[sickpuppy1]

That's a really interesting thought. Counter-intuitive. Rough or "bumpy"

That's a really interesting thought. Counter-intuitive. Rough or "bumpy" surfaces won't stick to things because they are composed of lots of high and low spots. So there's limited level area to stick to something. But highly polished flat metal is the opposite: Less bumps, more flat consistent area. Perfect for sticking to things.

I guess if you wanted a polished surface you'd want some kind of texture or wave or bump to it to minimize sticking. Interesting....

Brian.

The logic behind it is that when you slice most foods you don’t notice, but with chees and such, it will tend to stick or suction to a super smooth surface. Kind of creates a vacuum. The rougher surface allows air gap and breaks that vacuum effect. The screen protector on your phone works the same way.