New WE owner/sharpener…. The more I learn 2/5

[Braden Wright]

Intro/Question 1 are here: https://knife.wickededgeusa.com/forum/6-techniques-and-sharpening-strategies/13343-new-we-owner-sharpener-the-more-i-learn-1-5

(2) What level of finish do people use for different knives/tasks? And can too much finish be a bad thing?

Background:
For progression I’ve tried out using (a) 100-1k diamonds -> ceramic (b) 100-1k diamonds -> ceramic -> 2/3k choseras (c) 100-1k diamonds -> ceramic -> 2/3k choseras -> 5/10k choseras. I noticed when dragging my thumb over the blade that at different point in the progression the sharpness feels different. I tried to do things like cutting a piece of paper or shaving arm hair but was having trouble. However I used the knife a little and it seemed really sharp. I did some push cut tests on cardboard and it was sliding through like a hot knife through butter.

Which lead me to question, can too much finish be a negative thing (I know its not always needed) but can it actually be “less sharp for a task” b/c someone went to .025 micron diamond spray lapping (or its just overkill that may not be needed)

[Zamfir]

I think so yes.

On my EDC knife I now finish with the 1K plates to leave a toothy edge..This is where you feel it and it is like it pulls at your thumb..it “feels sharper” to me.. But I can not split a hair with it. If I move on my my grit progression and strop more heavily, I can get to hair splitting..but it is now more of a razor edge and smooth..Those micro serrations left by the 1K help me to cut the things I usually cut with an edc… That almost indestructible plastic crap they put around tools that you almost can not cut with normal scissors…cardboard tape cloth rope plastic bands around boxes etc. The serrations help to bite better rather than just gliding off the plastic and such. Will still slice paper nice..but just not hair splitting..but I would rather have the teeth. At some point I will experiment with leaving off on the 800 and do some very light passes with the ceramics to polish the teeth a bit but keep them in tact..

Many people here can get hair splitting and shave sharp with just the 1K stone finish with the teeth..I am just not that good yet..And the plates need to break in some also.

If I am feeling fancy about a knife..and thin the edge a bit I may polish it then put on the mini bevel..not micro where you can not even see it..but a wider bevel like say Thinned to 15 or 17 then sharpened to 20 and left toothy as I did on my hunting knife. It looks neat to me..and the polished edge is smooth so things pass over it easily after cutting is done by the 20 deg apex.. But mirror is just for looks I think.. you can get a functional almost mirror surface with the ceramics..

The nice thing is you now have the sharpener..and on your knifes..you can try different things. Someone here told me to just ignore the micro bevel stuff at first..work on single bevels and get those real good..you can always add a wider micro bevel later.. Use the knifes..see if the edge is doing what you want..then try something else.. This will also bridge to your other question on what angle for what blades and such..no magic number..it all depends on what the steel is and what you intend to do with the knife is what I am learning. But a general rule of thumb seems to be..around 20-22 for EDC with good hard steel..But you can get away with less with the real hard stronger stuff..zdp189 and such..There are so many combinations it boggles the mind. I ended up settling on 17dps on most everything..it is a middle ground of what people like to have on the higher end steels..some love 15 some love 20..I settled on 17 for testing reasons..I am playing with different types of steel and seeing how they perform..well..I am trying them all at 17 to see how they hold up. at some point I will change them up one way or another depending on what I am using them for or..well just how I feel that day..lol. Because I can.. :silly:

[tcmeyer]

The first serious knife I sharpened was, of course, my old Buck 110. I gave it the full treatment, all the way up to 1600 and then polished it with my leather strops with the 5 & 3.5 micron diamond paste. Wow! That sucker was sharp. Next opportunity I had, I reached for it when I needed to cut a 3/4″ hemp rope out in my garage. I was absolutely stunned when the knife simply wouldn’t begin to cut this stuff. Then I read a little bit about how knives had to have a “toothy” edge to cut into tough, fibrous material. I found that was true in the kitchen too.

The polished bevel is of great benefit to promote ease of progress through the stock being cut. But a “toothy” edge helps pick up fibers and promotes good cutting efficiency through most materials.

For most knives, I take the very edge up to 800 or 1000 grit, then polish the “back shoulders” to a good shine. Or I’ll finish to 1000, then give the bevels a light polish using the micro-fine stones (1.4 & 0.6 micron ceramic) – maybe 5-10 very light strokes. The objective is to leave the micro-serrations produced by the 800/1000 stones, but polish out the high-friction finish on the main bevel faces. This is also a reason many go to a micro-bevel.

[Mr.Wizard]

bwright, here is an entire thread on this subject: The perfect combination of toothy and polished

The first serious knife I sharpened was, of course, my old Buck 110. I gave it the full treatment, all the way up to 1600 and then polished it with my leather strops with the 5 & 3.5 micron diamond paste. Wow! That sucker was sharp. Next opportunity I had, I reached for it when I needed to cut a 3/4″ hemp rope out in my garage. I was absolutely stunned when the knife simply wouldn’t begin to cut this stuff. Then I read a little bit about how knives had to have a “toothy” edge to cut into tough, fibrous material. I found that was true in the kitchen too.

It is possible that you rounded the edge while you polished it? Here I go quoting Cliff Stamp again, but he does write quotable things.

… I went to cut some paracord to see how it would perform and though it will easily push through it, the cord would slick along the length of the edge. This was extremely sharp but not aggressive enough though you could feel the ‘grab’ when you felt the edge with your finger.

As an honest question, why would you call the edge sharp if it just slid along the paracord? Put it another way, if you left an edge really coarse, and after use it had dulled it would likely do the same. Both edges can’t cut the paracord, why is one dull and the other one sharp when they both physically behave the same way if you try to slice the rope?

Here is a simple experiment :

-take a piece of rope (or something similar)
-sharpen a knife with a very coarse grit, say 36
-make a slice for a specific length and record the amount of force used

Now increase the grit and repeat until very high grits (8k+) or you become bored. The force should keep decreasing until it hits some point at which a draw isn’t needed as it will just sink through the rope once that force is applied.

If at any time it slips then the knife didn’t get sharper, for some reason it was dulled by the higher grit, often through apex rounding. Now a lower grit finish in some cases may (will) produce higher edge retention, but it can’t produce higher initial sharpness.

The main reason it is often argued that it does is because there is an over reliance of strops/buffers to produce polishes which tend to rounding apexes. Often was is being compared then is a coarse edge with a V-formed apex vs a polished edge with a rounded one.

As a point of interest/reference, with 1/2″ hemp you should be able to do a cut with a 2″ draw with a load of 4-5 lbs with a very sharp edge (with a thin cross section). With a very coarse edge the force will by higher, ~10 lbs with a 36 grit edge.[/quote]

[Braden Wright]

Thanks everyone good input…. gives me a few more things to try.

I think part of my confusion of can to much finish be bad is summed up here…. so maybe I missing something…. b/c I had been through posts “The perfect combination of toothy and polished” and some others…. and to me seemed like a lot of people like toothier edges for slicing…. But the in Cliff’s quote above…. he asks why it would be sharp if it can’t cut paracord…. and purposes that every girt you increase to test and that it should cut with less force which to me means its getting sharper every grit you go up which sounds like the opposite to me?

Being a noobie its very possible that I’m rounding my apex with my higher grit I supposed (I did read recently with water stones sounds like too much slurry, paste can round the edges, I haven’t lapped but I know that can round it).

I have an angle cube I’ve been trying to keep it within .20 degrees I’m thinking maybe this isn’t accurate enough?

I think I need to start doing some consistent tests to see how I’m doing I like the idea of cutting hemp and someone post a video of whittling wood.

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