Sharpening is hard

T

THG

Joined
May 18, 2008
Messages
3,644
I can't seem to get it right. I bought a DMT Diamond Whetstone - Fine grit. I have a kitchen sharpener rod which I assume is rather coarse. I can get my knives quite sharp with it. Then I take it to my new Fine Whetstone... And my edge just goes to hell. How do you guys do it? It's really frustrating.
 
what is happening to your edge?

new DMTs are coarser than advertised, they need a little break in.
 
hardheart said:
what is happening to your edge?

new DMTs are coarser than advertised, they need a little break in.
Click to expand...

I don't know what's happening... It's getting dull as hell; that's all I can say. It doesn't catch my fingernail, and it doesn't slice through paper.

I don't know how to describe my sharpener rod. I'm sure it's a kitchen sharpener. It's made of metal, so I'm pretty sure it's not ceramic.

Dunno what the deal is, though. I can slice paper and catch my nail easily with the rod, but this "Fine" whetstone doesn't seem to do shit. I'm sure my angle is consistent. Maybe I should just return it?
 
It sounds like you're forming a burr, but not getting it off again. Do you know about raising a burr, then removing it?
 
When you sharpen one side of a knife, eventually you will have removed enough material that a burr is formed. This happens when the edge you are sharpening is sharpened down to the point where it meets the other edge and forms a burr where the two angles meet. When you sharpen, the goal is to sharpen one side while maintaining as constant an angle as possible, untill a burr is formed along the ENTIRE edge. Then, flip it over and repeat the process, again, untill you have a burr along the entire edge. Once you get to this point, it's time to switch to a finer stone to REMOVE the burr. A burr left on the blade is what's known as a wire edge. It's very sharp, but it will fold over and become dull in a heatrbeat. At this point, on your finer stone, make one stroke, lightly on each side, alternating for 3-4 strokes. Stop and check for a burr. The easiest way to check is ot use your fingernail right at the edge to see if it catches. The burr must be removed from the entire edge to be sharp. Be sure to check both sides. You can also increase your angle slightly and hake a couple of alternate strokes. This method is called "double edging" and it works really well, it's the method I personally use, and alot of other folks arround here too. Hope this helps, if you need any more info, drop me a line, I'll be glad to help. Good luck.
 
But after removing the burr, the blade should still catch the nail, right?
 
Yes, after the burr is removed you will have a sharp knife. As long as you didn't round over the edge.
 
Well I guess I don't have a sharp knife then... lol

I think I just need practice... Thanks for your help.
 
A good place to start would be to buy the book The razor edge book of sharpening, by John Juranitch. That's the Bible of modern knife sharpening. Just remember: you don't have to buy his product to sharpen knives. Whetstones are fine, they were good enough for our fathers and grandfathers, and they could sharpen as good or better than most people today. The book is full of good info, and really teaches the basics very well. It's the best money you'll ever spend, except maybe for some new whet stones and knives.
 
I usually start with a coarse DMT hone (blue), then a medium (red). Once a burr is formed I go to the fine (green). If the blade is just lightly used then just the green will do, most of the time. Hope this helps.
 
THG said:
Well I guess I don't have a sharp knife then... lol

I think I just need practice... Thanks for your help.
Click to expand...

Do you know anyone who can sharpen a knife freehand? If you do then have them show you. It is usually easier to be shown than have it explained. If not then read the books and practice.
 
I would also recommend the book by Juranitch. It will teach you the trick with the burr and its subsequent removal. You'll have a shaving sharp blade with a bit of patience (important!) even if the blade doesn't look too pretty afterwards.
The author does however basically claim that his sharpening method is the one and only way, which is simply not true. None the less it's the way I started sharpening properly and can recommend in highly.

btw. you're right, sharpening is hard, but I think that's why I do it :)

Spitz
 
Sharpening is hard, that's true. But it is not rocket science either. You need to learn about the basics of knife sharpening (what is going on in your edge when you sharpen it) before you can really sharpen anything. I recommend you getting one of those books the guys are telling you about or just spending a lot of time reading here.

Mikel
 
You can also practice hand sharpening by taking a blade that you consider sharp, applying permanent marker to the edge bevel, and then doing it one stroke at a time. You will be able to see where you are removing metal as the marker will get worn away. When you are removing the full width of the black marker and no more or less, you'll at least have got the hang of the angle you are shooting for and how to hold the knife to keep that angle. From that point, its just a matter of progressing through the stones.

...or you could get a sharpening device like a lansky, sharpmaker, or edgepro.
 
smitty0331 said:
When you sharpen one side of a knife, eventually you will have removed enough material that a burr is formed. This happens when the edge you are sharpening is sharpened down to the point where it meets the other edge and forms a burr where the two angles meet. When you sharpen, the goal is to sharpen one side while maintaining as constant an angle as possible, untill a burr is formed along the ENTIRE edge. Then, flip it over and repeat the process, again, untill you have a burr along the entire edge. Once you get to this point, it's time to switch to a finer stone to REMOVE the burr. A burr left on the blade is what's known as a wire edge. It's very sharp, but it will fold over and become dull in a heatrbeat. At this point, on your finer stone, make one stroke, lightly on each side, alternating for 3-4 strokes. Stop and check for a burr. The easiest way to check is ot use your fingernail right at the edge to see if it catches. The burr must be removed from the entire edge to be sharp. Be sure to check both sides. You can also increase your angle slightly and hake a couple of alternate strokes. This method is called "double edging" and it works really well, it's the method I personally use, and alot of other folks arround here too. Hope this helps, if you need any more info, drop me a line, I'll be glad to help. Good luck.
Click to expand...

That's exactly what has to be done. I would only add this: light hand, slow move. No need to put strength, you would lose precision and tear off the diamonds from the sheet of nickel of the DMT whetstone.

dantzk.
 
A comment on the stones versus DMT brought up above. It is absolutely true that our forefathers used stones to great effect, and they're still capable of doing an excellent job.....on SOME knives. For the most part, you'll be okay with Norton/Arkansas stones if you're sharpening kitchen knives or less expensive modern hunting knives that use simpler alloys. They also work well as finishing tools on an edge that's already mostly sharp and just needs final touchup.
All that said, though, higher end knives are run higher on the Rockwell scale than they were "back in the old days." You can test old WW2 kabars, Marble's hunting knives, or modern Randalls (which still use very similar steels and heat treat methods to what they used 60 years ago) and they test out in the mid 50s HRC. Stones do fine on that. Modern cutlery is genereall run much harder, though. Also, they're more complicated alloys with higher wear resistance in many cases. If you're trying to do serious metal removal on 3V, D2 or BG-42 on a coarse Arkansas, you're going to be at it a LONG time, and you're also going to wear your stone down pretty fast. Also, the longer the process is, the harder it is to keep your attention on it and you're technique will likely suffer.

So, don't ditch your DMT---it's a really superb sharpening implement, its abrasives are much harder than any steel can ever become, and its surface is non-deforming, meaning that while it will, eventually, lose the ability to cut well (though I've had several for years and they're still trucking along) it will remain flat and consistent for you to form an edge against. And no, I'm not saying 'stay away from traditional stones' by any means. Just don't get into the thinking that something is better simply because it's traditional. I guarantee there were a bunch of grumpy old guys at the beginning the Iron Age who would tell any young guy they could grab that if bronze was good enough for their fathers... ;)
 
Over time I have tried different methods for sharpening knifes, after a while I had too many methods in my head and wasn't sure which was the best. Juranitch's book straightened me out and made me realize that I knew how to sharpen a knife just fine but I had to forget all of the other hype and superstitions about sharpening. I like a coarse diamond whetstone when I re-profile a blade. It's not that I think that the original bevel is bad all the time it's just that I can't reproduce that bevel by hand. I know the compound bevel that my hand produces and I can recreate it in the dark (that does bother my wife when I sharpen knives by the glow of the television while watching Law & Order re-runs). I've still got some techniques to master to keep from scratching a blade sometimes but with concentration I get it done.
 
+1 for The Razor Edge Book of Sharpening.

Before I bought the book I was getting good sharpening advice from knife forum members, but it was all in bits and pieces. I didn't get the "big picture", and finally fully understand sharpening theory and practice, until I read the book. It took the mystery and complexity out of sharpening. I now see sharpening as quite simple, and my knives are sharp. The book has lots of diagrams and photos, and it's easy to understand. I highly recommend it (and the Razor Edge hones).
 
IMGP0242.jpg
[/IMG]

There's my equipment. I have no idea what the rod is, although I can put a magnet to it and it'll stick. It must be made of steel, then.

Still, I am able to get a really sharp edge with this rod, but my stone (marked "Fine") completely screws it up.
 
You must log in or register to reply here.
Back
Top