Whatever the method you use, the main thing people who "can't sharpen" need to understand is what you're trying to accomplish.  It doesn't change with the method. 

Going left to right, a magnified cross section of your blade.  Left is dull with the ideal edge geometry in red.  That red geometry needs to be consistent, it doesn't necessarily need to be flat, or concave, or convex - it needs to be consistent along the length of the blade.  Next to the right, the stone/belt/diamond/whatever in green, establishing your bevel.  The blue line is the burr.  The burr is formed because your grinding tool requires a particular amount of pressure to cut, no matter what kind of cutting instrument it is, it needs pressure.  The steel can only support itself at a certain thickness before the pressure necessary to cut overwhelms it, and it flexes away.  This is also referred to as the wire edge and it's important.  I've drawn it flexing to the left.  You know the right side is "sharp" when you put your finger under the left side and can feel that burr as you pull your fingertip across it.  No burr?  Not sharp.  Keep stoning.  It's called a wire edge because in the next step, with many alloys, when you strop this away, it will often peel right off in a thin wire that you can see.  It's generally .001" or .0005" thick, depending on the alloy, angle, and method of sharpening.  Stropping removes it by 2 actions, bending it away from the base metal, back and forth until it fatigues, and also if you're using a compound, through another abrasive process.  Note the green line is a more obtuse angle than the sharpening line.  This is necessary to really remove the burr rather than creating a false edge with a burr that rolls over the first time you cut with it.

When you're done, you get the right most in blue, and that's sharp.  The degree of sharpness will be the product of a number of different variables, such as how polished the edge is, the alloy and thickness behind the edge, and angle of the bevel will determine how thin of a point can be sustained.


This might be elementary to most but I find a lot of people don't understand the burr and the importance of it in sharpening.  If you haven't "worked up a burr" you haven't taken the edge far enough down to be sharp.  If you haven't removed the burr, it may have rolled over and is performing like it's dull.

He already has a not very sharp knife.

This is good stuff.

Read it, learn it, live it.

I've had good luck with Edge Pro. I did get a little carried away. I built my own stones buying blanks from congress tools. Got way to O.C.D. about carrying a scalpel sharp knife. Built leather strops with different compounds. Then balsa with diamond spray down to .5 micron. I have had no problems sharpening any of the so called Super Steel ie. S90v, s110v, cpm 10v, CTS 204P, and k390 to a mirror finish.  Warning sharpening steel can become very addicting. Attached File

Tell me more about this diamond spray. 

Love the Gayle Bradley and S110v Manix. Great knives

.5 Micron Diamond Spray https://www.amazon.com/dp/B006WRH3IM/ref=cm_sw_r_sms_apa_esMSybW9BY9E5?tag=vglnk-c102-20

After looking on their website they now have a .25 micron


Thanks i really like my Bradley I did a wave mod that duel functions as a bottle opener its one of my favorites, and I love CPM-m4.

Thank you. 

M4 is like steel with a cheat code. It. Just refuses to dull. Wood, cardboard, plastic or copper it just refuses to dull.

It's got a nice ballance and doesn't get chipped like my s110v if I abuse it a little. A chipped edge on s110v even if small can take a while to reprofile.

Do you run into the same issues with synthetic Japanese water stones?

I've got a set of Shapton stones and a set of Choseras.

The only super steel I have right now is S30V, and I was able to put a very nice edge on it with my current stones, but I'm looking at getting some knives in M390 and S110V etc.

There's just no point.  Synthetic diamonds cut everything and the do it faster for longer for less cost over the life of the tool.

I don't understand why people outside of die makers even bother with stones, synthetic or natural.

I have more experience sharpening woodworking chisels and plane irons than knives.  Typically, the tools are made from A2 steel or Oil hardening steel.

I have found the fastest way to sharpen by hand is mostly using diamond stones, but that only gets me to about 1200 grit.  That simply doesn't produce a sharp enough edge in woodworking tools.  I follow this with a 5000 grit and then a 8000 grit Japanese water stone.  (Japanese water stones are flattened by the course diamond stone first.)  The chisels and plane irons will shave hair at that point.  Stroke it on a leather strop charged with green chromium oxide and you get a more consistent shave across the width of the entire tool.  Edge is more perfectly polished as are the backs.  Stropping added a next level of perfection and ease of sharpening that was worthwhile.

After the tools are sharp, frequent stropping will keep them that way or occasionally dropping back to the 5000 and 8000 grit Japanese stones. 

The chisels and planes will cut end grain like a salami slicer at that point.  A joy to work with sharp tools once the meaning of sharp was understood.

One day, I will buy a nice wide 25 or 30 mm Japanese chisel made with laminated steel.  I feel I can extract the value of the steel now that I am better at sharpening.

i don't have any knife guides, so I use the same system for knives.  I can get a knife to shave hairs this way, but I believe one of the guided systems might make it a little easier.  It's the final 8000 grit and/or stropping that puts that finishes the tool or knife to incredible sharpness.  I don't spend a lot of time at the final stages as by that point your tool is already shaped and you are polishing the blade and removing the bur.

If you ever need more blanks, Home Depot sells the same size aluminum strip. Cut off a piece for the bottom and bevel the ends, cut off a piece for the top, smooth the cut edges. Stick them together with 3M 77 spray adhesive and clamp them. That's what I did to use the 3M microabrasive PSA film on my Edgepro.

I use the Veritas jig for my chisels and plane blades. It ain't cheap, but it works well.

Sharpmaker is your answer.