Sharpening to a burr, but still not "sharp"

Joined
Feb 15, 2012
Messages
370
Maybe I'm not doing things properly, but it seems like when I sharpen a knife, it gets sharp, it passes the "3-finger" test, but it doesn't really seem to shave well.

My method, without going into stone progression or anything, is to sharpen both sides a bit at a time until I get a burr to form, in which case I get it to form on the other side, and then I sharpen each side lightly and with small amounts of passes until the burr ceases to exist. This, I thought, was how you get your knife to it's sharpest point. Like I said, these knives pass the three finger test with ease, but shaving with them doesn't seem to work very well. In fact, I just sharpened my Griptilian for the first time after having it for a little less than a week, and while it didn't need much work, it shaved better BEFORE I brought it to a burr :confused:
More info on the method used for this particular knife: I only used a DMT Diafold Fine and I kept it at factory angle (which my guess is in the 25-30º range). It took me about 90 seconds to get a burr to form, and it was quite a small one. Do I need to form a large burr? I've heard the phrase "pre-burr" before but I'm not sure what that is/means. Once it formed I flipped the knife over and formed the same size burr on the other side, then worked on each side very lightly until I couldn't detect the burr with my finger or fingernail anymore. As a side not, the knife DOES shave, it just seems to pass over the lighter hairs on my arm, and seems to be shave less hairs off per pass now. I haven't stropped yet, and I don't believe I have a finer-grit stone than what I used

I've never gotten a knife to pop hair, and frankly I don't think I need to. However, my general rule is that my EDC knives need to be able to shave my arm hairs before I'll carry them. Any suggestions for improvement on my technique or ideas on what I may be doing wrong would be greatly appreciated!


UPDATE: I decided to try out my fine oilstone for a bit (again only spending a couple minutes), then a few light strokes on the Diafold (as it feels to have less draw), then I stropped it and now it's shaving better, but I still feel I should be getting more satisfactory results lol.
When looking at the blade it's obvious I haven't taken that much steel off, as I can still see some of the deeper remnants (lines) of the initial sharpening on the edge. Would you guys recommend using a coarse stone to get more steel off and get the whole edge to that mirrored finish? Obviously I'll do it eventually, but if it'd do something for me other than make it look more aesthetically pleasing I'm game to taking a bit more metal off now

(If you can't tell, I'm babying my Grip even though I want to use it as a handle-whatever-I-need to type of EDC)
 
Last edited:
What blade are you using as a example? What steel?

Are you completely erasing the factory grind marks?

First problem I see is factory angle, most of the time its 40-50 inclusive and that's not really easy to get a high degree of sharpness from such a thick edge angle. Add in the freehand wobble and you eventuality make it too steep to sharpen. You are probably getting as much sharpness as would be expected from the current edge angle so first solution would be to lower the angle.

Your method sound spot on though I think you may be relying on the burr too much without viewing the edge as a whole.
 
I agree with knifenut1013. I just spent several hours over the last 2 days resetting the factory edge bevel angle on a traditional folder (D2). MUCH easier to sharpen now.
 
What blade are you using as a example? What steel?

Are you completely erasing the factory grind marks?
Benchmade 551 Griptilian with 154cm

No I am not lol. This is the first knife I've bought that was worth more than $50 (though I have ones worth more) and I guess I'm just worried about hurting it, so I'm going really light on it haha. Tomorrow I'll try lowering the angle a little bit, but I'm going to take my time on it and make sure I don't get the bevels uneven (I am crazy weird about symmetry).

I bought this knife because I knew it could take a beating and I'm treating it like it's made of thin glass :rolleyes:. I guess I have to get over the price tag and just treat it as a great tool.


Also, can you elaborate on this last part:
Your method sound spot on though I think you may be relying on the burr too much without viewing the edge as a whole.
 
I have used and abused my ZT 0551 and its a limited run folder with a value over $200, and I still carry it everyday. Once you can look past the price you will gain more enjoyment from your knife.

If you are not removing the previous grind marks you are only scuffing the surface. Need to grind further to make it work correctly.

In the last part I mean exactly what it sounds like. Your focus was so high on the burr that the bevel as a whole was neglected in the sharpening process, you must sharpen the bevel as a whole instead of just looking for the burr.
 
I'd add that some factory bevel are concave/hollow, if they use wheels. Hand sharpening usually result in slight convex. To get to the bevel thoroughly might need some work as you're changing the bevel from )( to () (exaggerated). You'll see that the edge and shoulder got touched but not the middel of the bevel. Like this : |) .. the straight line only touched the shoulder and edge. To get to the middle of the hollow, you'll have to remove material from the 'tails' of ) until it's |.

You're luckier if the factory uses belt that result in slight convex. You'll see that somewhere in the bevel got touched but not the rest. Like this |(.
If you touched the edge, but it's more convex than your sharpening method (assuming using jig = flat) then the rest of the bevel would not be touched. To get it conforming to your |, you hve to remove the 'belly' of ( until it gets |.

Both this examples assumes | is your stone and ) is the concave/hollow of the blade bevel, while ( is when it's convex. Stone at the left side, blade edge at right side. Hope this is not confusing :)

Use the sharpie marker trick, you'll find out which one is which.
 
Last edited:
Thanks Knifenut, I'll be hitting the coarse stone in a couple minutes and I'll pay more attention to getting an evenly ground bevel.

@Chris: This is an interesting thing to note. I'll have to say mine must have been concave a little bit, as it does seem untouched in the middle of the bevel. Thanks for the "illustrations" :D I didn't find them confusing at all
 
...you must sharpen the bevel as a whole instead of just looking for the burr.

That's true. Just getting a burr doesn't really mean a whole lot; a burr can easily be formed on a very coarsely ground, 1" thick 90-degree edge (as an extreme example). That doesn't make a very good knife edge ;)

Whether sharpening, honing, or polishing an entire blade, the most important step is to get the scratch pattern straight, evenly flat or evenly convexed, and consistent at your coarsest grit before moving up to the next-finer grit. Regardless of any burr.

It seems like extra work at the outset, but things actually go much quicker overall and you get much better results if you start with a great "foundation". Using a Sharpie or layout dye helps, using a magnifying glass or jeweler's loupe helps even more.
 
As water is a lot cheaper than oil (free) I've been using water on my oil stone, and just washing it off after honing for awhile. Is this going to work well, or should I stick to oil? If it's cool to use water, would keeping it in a water bath like people do with their stones be a good idea?

EDIT: Whoops, forgot to reply to you, James. I do use the Sharpie method, and I've been paying close attention to making sure my scratch pattern is the only one I see and that I've got a consistent burr across the whole blade. After an hour and a half on the coarse stone I've got it down to about an inch around the tip and about a half centimeter and the very bottom of the blade that I'm still working on getting down.

I've noticed that despite trying to remain even on both sides, the bevel on one side is still larger than the other side. Is is just that I'm not using the same angle on both sides or what?


EDIT 2: Well it seemed like things were going well but after I stropped it it seems to be barely shaving and not even push-cutting paper. I think I'm going to hit the fine stone again and skip the strop as I guess I'm not using it properly and rounding the edge

EDIT >9000: I've worked it with the fine stone again and it's shaving decently. I don't think I took it down to a low enough angle though, as I only dropped it a couple of degrees. I'll probably keep it where it is until it needs some work again and then drop it as I just spent the last 2 hours and 45 minutes sharpening it ;)
This oughta be the last update of the night. I use edits instead of double+ posting as I've learned it really really annoys some folks haha
 
Last edited:
Great it worked out! When I thinned down my 9Cr13MoV Navy (labelled as 440C but I think it's Chinese steel), it also took me hours. However, once you're set, touching up and maintenance is a breeze.
 
Last edited:
Breaking out this old thread because I don't want to start a new one. I think I found out that the problem was the stone I was using. I just sharpened up an old slipjoint I've had since forever ago and I just couldn't seem to get the knife sharp! I raised a burr on both sides a couple seperate times, and filed away slowly until I couldn't detect it anymore. I grabbed some paper, went to cut it, and it was HARD to cut through it... I decided I'd just use my DMT Diafold Fine as it sharpens faster than an oilstone, and the scratch pattern became MUCH smaller and the knife started slicing through the paper like it wasn't even there...

I guess when you buy a stone for like $7 you get what you pay for. My next investment will DEFINITELY be the double-sided DiaSharps from DMT...!
 
My method I use the DMT coarse (blue) on really dull knives and to re-profile.I bring it to a burr on both sides and then move to the fine (red) and do the same thing. Finally I knock the burr off and polish with the very fine(green) and fine polish with the Ultra fine (white). I use the the very fine and ultra fine for touch ups after sharp.
 
Back
Top