How To Get Sharp Knives

Mister Coffee said:
Took forever to get a burr on each side. It was after the fourth time of getting a burr on each side but no edge on the knife that I lost my temper and really went at it. This knife had the factory edge when I started. A full flat grind to the apex. I tried everything: micro-bevel, bevel, raising the bevel. I used a Sharpie throughout, and checked the edge with a loupe as I went along. The stone was brand new and cleaned after every sharpening. After the third sharpening, I stropped the edge, and it took a polish, which I didn't even want.
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Yeah. You’re not overdoing it at all.👌
 
Best to hone your knives when you're not pressured. I sharpen freehand and usually start with a coarse grit (220 DMT) if I need to set the bevel (an angle guide helps), then proceed to finer grits, usually no more than DMT red (600 grit). I find the DMT green (1200) grit great for a polished edge on high carbon steel wood carving tools, but high carbide volume powder steels like S30V and cousins cut better with a slightly coarser edge.
 
Alberta Ed said:
Best to hone your knives when you're not pressured. I sharpen freehand and usually start with a coarse grit (220 DMT) if I need to set the bevel (an angle guide helps), then proceed to finer grits, usually no more than DMT red (600 grit). I find the DMT green (1200) grit great for a polished edge on high carbon steel wood carving tools, but high carbide volume powder steels like S30V and cousins cut better with a slightly coarser edge.
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Thanks, Ed. I lost patience somewhere during the fourth sharpening session, and just did anything to see if the knife would respond. Which it did not. So, I have to step back and think things through once again. By the way, 220 DMT is not Course. It is Extra Course. If I had had one of those, I'm pretty sure I could have ruined the knife in only three sharpening sessions.
 
D DavidABQ Thanks, Dave. It's a frustrating moment, but I'll figure it out. Sharpening is fun for me because it allows me to learn something new (I don't work in a profession that uses knives). This is just a setback. Like Obsessed with Edges Obsessed with Edges with edges said, I could step back for a bit and regroup.
 
Blues said:
Unless there is something wrong with the heat treat or steel...it's probably down to a combination of technique and possibly either not creating a burr...or failing to properly remove it.
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I know I got a burr on both sides. As for "failing to properly remove it," I don't know. If you can't feel anything on either side, and you've stropped the knife, and drawn the edge across a piece of wood, what do you do?

Blues said:
It takes time...but don't give up. It's worth learning.
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I agree. Thanks for the words of encouragement, Blues. I value what you say.

Blues said:
I'd recommend using the bench stones to thin the bevel and reach the edge, (creating a burr),...and when you think you're just about there...finish on the Sharpmaker, (light alternate strokes), and see if it's sharp then.
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Finish on the Sharpmaker? But that's cheating, isn't it?
 
Tuna said:
I had the same struggles for a long time. I never got great edges until I used the Sharpie trick to draw on the bevel to see where I was actually grinding with the stone. Once you determine what angle you need to grind at to reach the tip of the bevel, grind that angle until you form a full length burr. Flip and repeat. Once you remove the burr after forming one on both sides your blade should be shaving sharp.

also if youve been going at it with the same stone for a while, maybe it needs to be cleaned off so it cuts the metal efficiently again
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Tuna Tuna xbander xbander Thanks for the posts. I did use the Sharpie trick. And I stopped frequently to examine the edge under 8x magnification. The edge looked like a mess, even before I started, so I decided to raise the bevel. I got it to look clean and regular. Still wouldn't cut, though.
 
The zwilling edge looks well ground, so far so good! The steel is softish which makes it easy to grind. Of course you can feel the burr?
 
A real simple set of tests for assessing your edge:

•Look at the knife edge-up under bright light. Any spots that reflect are dull.

•Rest the edge lightly on your thumbnail and rock it side to side. If it sticks in both directions, that zone is sharp. If it glides in one direction but slides in the other, the sticky side has a burr on it that needs fixing, so work on that side with a few stroke to even it up and retest. If it slides in both directions it's dead dull.

•Once the edge passes the thumbnail test, see if it'll shave arm hair. If good and crisp, it should at this point. If not, use a few light finishing strokes per side on a fine stone.
 
Obsessed with Edges said:
Take a breather for a few days. Fall back & regroup. Eat well and sleep well. Let it all percolate in your mind while doing so. But don't stress over it. The pieces will begin to fall into place if you allow yourself the time & the rest to let it happen. I'm pretty sure everyone goes through this learning curve in a similarly frustrating fashion. I know I did. It'll start to click, in time.

When I was learning, I spent a fair portion of the 'off-time' just stropping a blade on a paddle strop with green compound, while relaxing in an easy chair in front of the TV and sipping from a glass of wine after a good dinner. Just that simple routine of sort of casually, almost absent-mindedly stropping that blade managed to get my hands conditioned to the feel of the bevels in flush contact. Didn't realize how valuable that would be at the time. But I discovered later that my hands had 'learned' much of the touch for sharpening by doing this, even if my conscious mind still felt like I didn't know how to progress. It just happened, and that surprised me.
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Freehand sharpening is all about feel, you got it from stropping! For me it was first polishing bevels by hand, practicing sharpening,then grinding on a platen that finally gave me that feel of flat.
 
FortyTwoBlades said:
•Look at the knife edge-up under bright light. Any spots that reflect are dull.
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yee. the reflective spot is either dull (as in "rounded, not apexed") or it is macroburr. just by seeing reflections edge-up, one cannot tell for sure if it is macroburr or a non-apexed ("flat") spot.

and if one cannot see reflective spots edge-up anymore, then it only means that the edge has been apexed yes and that there is no more macroburr. however, there can still be microburr right on top of the very apex. it is invisible thru the edge-up lighting test per definitionem. a cute gal 😘 on this forum introduced this definition for distinction. in theory it is not necessary to distinguish between macroburr and microburr (and master sharpeners doht do so and to me either is just "burr") but in conversation and in practice it makes sense to
 
Mister Coffee said:
Thanks for the posts. I did use the Sharpie trick. And I stopped frequently to examine the edge under 8x magnification. The edge looked like a mess, even before I started, so I decided to raise the bevel. I got it to look clean and regular. Still wouldn't cut, though.
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What steel are you sharpening and what kind of stone are you using? What do you mean by raise the bevel?
 
Mister Coffee said:
Buy new ones.







Gentlemen, the sharpening game has got me beat. I've spent a week trying to sharpen one knife, and all I have done is make it more dull. I've tried bench stones, the Sharpmaker, strops, ceramic rods. The whole situation is baffling to me. Extremely frustrating. I just can't figure this out.
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Geometry geometry geometry geometry geometry geometry.

I rarely meet a factory grind that sits well on a stone.

Don't make things complicated, and don't be too slow and precise, and don't work on too fine a stone. Your only goal when you first touch a knife that has never seen a stone before is to grind down to the edge at any angle you so please. That requires a coarse stone, and sometimes a good deal of patience.

You don't need to measure angles, or have any silly guiding contraption, or anything. I recommend starting with a medium, or combination fine/coarse Norton India stone and 3-in-1 oil. Both are cheap, easy to learn on, and inexpensive. Oil stones also have the advantage of raising a burr more noticeably, which is good for beginners as it indicates that you've ground down to the cutting edge.

Grind, grind, grind on one side until you feel a burr. Do the same on the other side, a roughly equal amount. Don't mess around counting strokes or alternating every pass. You can do that when you have the geometry down, and all those little nicks and cracks ground out of your blade. (Actually, definitely *don't* alternate every pass if you are trying to raise and are feeling for a burr, or you'll never get one...)

Even if you have ground the geometry down correctly, if you don't take out any little nicks in it, it will not cut smoothly or seem sharp. It will hang up when trying to slice through paper, and act dullish on other materials. You can know there are nicks in the blade by looking at it and seeing light reflect back in spots, or by feeling it catch when you run it through paper.

Then, alternate between sides to refine the edge and remove the burr, getting lighter as you progress, and do this until your knife cuts cleanly through a sheet of paper.

Once you get the basics down, you can refine that process. But the number one mistake I see beginners make is starting with too fine a stone, and not grinding down enough, because a factory grind, and especially a factory grind that has had years of wear and chipping, will require work -- sometimes a lot of work -- when it first meets a stone. Hence the need to start with a coarse stone, and preferably one that is flat and will stay flat for a while. If your stone is dished, as water stones quickly become if not flattened, it will be difficult for you to establish a consistently ground bevel, and it will make your life a lot harder as a beginner.

In the end, to help refine the edge and remove any burr, which may be a little difficult at first on a coarse stone, you can strop it on a newspaper or piece of leather on top of a hard wood table, but this is not necessary.

Here's a really straight forward and simple video I made on this, trying to cut through a lot of the confusion and things I see beginners struggle with. If nothing else, just watching someone demonstrate and explain helps:

When I first started sharpening, I struggled with a 1000 grit waterstone and a soft arkansas. Both were simply too fine to do the kind of grinding that needed to be done to set the geometry I needed (granted, I was sharpening woodworking tools, not knives), and the waterstone (which I didn't know I needed to flatten with a diamond plate when I bought it) wore unevenly very quickly such that I was never able to establish the geometry (perfectly flat back face) that I needed on my chisel and plane iron... So, I quickly learned the importance of a coarse stone, and a flat stones.
 
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Mister Coffee said:
Finish on the Sharpmaker? But that's cheating, isn't it?
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There is no cheating. Only getting a sharp knife, or not. I often do 99% of my sharpening freehand on my stones / plates...and finish with a few light passes on the Sharpmaker.

It's simple and effective. But it's only a suggestion. Do as you wish.
 
Blues said:
There is no cheating. Only getting a sharp knife, or not. I often do 99% of my sharpening freehand on my stones / plates...and finish with a few light passes on the Sharpmaker.

It's simple and effective. But it's only a suggestion. Do as you wish.
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Agree with the above. The SM is an effective tool. And using it after learning freehand on stones is making the best use of the tools available. Using the SM gets easier and works better with an acquired touch for freehand. That's the beauty and the epiphany of learning freehand sharpening - EVERYTHING works better after doing so, including all of the tools meant to make the process simpler for everyone.

I also utilize the SM after setting new edges by freehand on stones, and also for quick touchups after the fact. It's an enhancement device - not a cheating device.
 
Blues said:
There is no cheating. Only getting a sharp knife, or not. I often do 99% of my sharpening freehand on my stones / plates...and finish with a few light passes on the Sharpmaker.

It's simple and effective. But it's only a suggestion. Do as you wish.
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I was half kidding. :) Do you go through all four sharpening steps on the Sharpmaker, or just a a few light passes on the flat part lof the white rods?
 
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Tuna said:
What steel are you sharpening and what kind of stone are you using? What do you mean by raise the bevel?
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It's a Zwilling J.A. Henckels stainless steel. Not sure beyond that. I was using a DMT Course for the most part. "Raise the bevel" to me means sharpening at an acute angle—more acute than what was on there. What does it mean to you?

Edit: Maybe the correct term is "re-profiling." Not sure. I'm new around here.
 
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