View Full Version : Recent problems sharpening tip.. Also sharp but not cutting?

08-11-2012, 04:01 PM
Hey guys,

So recently I have had issues with the tips of a few knives. I get an even burr along te whole egde including very tip while sharpening.

When I go to slice about 2mm from the tip just won't cut the rest of the blade is fine?

Also have one knife I know Is sharp will cut onions just fine an tomatoes but when it comes to slicing red bell peppers or something it just won't cut all the way trough even with more pressure I can't figure out why??

Any ideas?

08-11-2012, 04:04 PM
what stones are you using? Do you have closeup pics of the tips of your knives (both sides)?

08-11-2012, 04:16 PM
Well the last time it had a full sharpen it was gesshin 400, 1k, red aoto, and Takashima

I normally only touch it up on the Takashima though which is what I did today and I can get some tonight when I get home.

Do you think it'd been from an uneven bevel?

08-11-2012, 04:42 PM
it could be... or it could be a faceting issue that is effecting performance (due to pressure since the stones you're using are pretty soft). It could also be not cleaning up the edge enough, edge fatigue that hasnt been taken care of, or a number of other things.

Eamon Burke
08-11-2012, 05:51 PM
I'm going to guess that you are using too much pressure and/or rounding over the edge from not adjusting your angle when sharpening the tip. Tips flex very easily and the curve of the profile means you will need to adjust the knife position relative to the stone.

Have you tried the sharpie trick to see where you are hitting?

As far as cutting the bell peppers, try a pull cut instead of a push cut or straight chop.

Dave Martell
08-11-2012, 10:07 PM
#1 - Make 100% sure that you've created a burr to the very tip.

#2 - Make 100% sure that you've removed the burr to the very tip.

08-12-2012, 08:26 AM
I will try this today again.

Have tried sharpie metho this is a recent problem with a knife I've never had problems with before, just the last two sharpening sessions.

I'm thinking it's either burr not removed or formed or Fatigued metal.

Will report later.

Eamon Burke
08-12-2012, 06:19 PM
Don't take this as me being a jerk, I sincerely don't mean to. This isn't really even directed at you, OP, since you clearly are just having trouble diagnosing the technique flaw that is causing the problem. But I had this thread pop into my mind a few times, as this a prime opportunity to point out the nature of sharpening.

Sharpening is easy.

You build a burr, you remove the burr. Polish what is left, the same way you made the burr.

There is really nothing else to it, it's just a lot of methods and tricks and skill builders. But the principles never change.

Unless you are doing a repair, changing the edge type, or altering the profile/symmetry, this is the entire world of sharpening. Build a burr->remove the burr->polish.

If I ever have a sharpening class, I think I will call it a Build-A-Burr Workshop.