Trouble sharpening from belly to tip

A

Against_The_Wind

Joined
Feb 15, 2022
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I have very medicore sharpening abilites, but when I do have some luck and get a knife sharp, I often fail to get that same consistent sharpness when I go from the belly of a blade to the tip of the blade.

I also notice that on some of my knives that came with very sharp factory edges, are not as sharp, when getting close to the tip of the blade.

Is it generally accepted for a blade to not be as sharp when getting close to the tip?

I recently just picked up a Opinel no.8 Stainless while traveling in Tennessee at SMKW. The knife was actually quite dull, but it was the last one in stock, so I bought it any way.

I was suprisingly able to get the knife quickly shaving sharp on my Sharpmaker, but the last half inch of the blade going towards the tip is still very dull. And I tried just focusing on that section only.

I also always lift up a little as I encounter the belly to the tip and with no success.

Using a sharpie, it looks like on just one side of the blade I may not be getting the edge, but its very close, hard to even tell with the sharpie.

If I'm not hitting the edge, I'm not very well versed on how to adapt, and I know the sharpmaker without the diamond stones is not very aggressive at removing metal.

I do also have the worksharp guided sharpener with more aggressive grit, but have not used it.

Again, I was able to get this Opinel very satisfyingly sharp, just not towards the tip, which will not even start to cut paper.
 
The angle of the edge often changes as you go along for various reasons ..
No matter the method , this is just the way of things .
Sometimes factory grinds are just Bad ( FUBAR ) .
And you have no choice but to lay down a new bevel / edge .
Problems with factory edges Usually are :
At the tip or forward part of the blade and toward the rear of the blade near the grip .
Simply because most knives are done on a belt grinder . And humans are not perfect .
So the resulting edge is not perfect . And any distraction or change in body posture or timing can result in FUBAR . ( Dips or hollows / changes in angle or something else like edge burn ! )
Anyone can FUBAR a edge ! No matter how skilled , just takes a fraction of a second on a belt grinder .
And a lot of these imperfections only show up when you re sharpen and some don't because of the re sharpening method .
 
You already know what is wrong because you tried "lifting up a little".
Maybe it's time you learned to free hand?
 
The belly and tip of the edge are sometimes ground at a much wider angle than in portions aft of the belly. This is usually because an upswept grind to the tip will be further into thicker steel nearer to the spine of the blade (assuming a tapered grind from a thicker spine down to a thin edge, as most blades will be). In an effort to make the edge bevels appear uniform in width along the full length of the edge grind, a wider held angle is necessary in the thicker portions. If the grinding angle were held exactly the same along the full length, the portions in the thicker steel will have noticeably wider bevels, which wouldn't look as attractive to most buyers.

All the above is to say: You might have to lift more than just a little, and maybe a LOT, when getting into the belly and tip of the blade. The Sharpie method mentioned earlier can help to see how much you need to lift, and if it's enough. For a visual training aid, I'd also suggest just holding different portions of the edge flush and still against a flat & smooth surface, like glass, and inspecting closely with a magnifier to see if the edge in that portion is making contact with the smooth surface. That'll open your eyes as to how much you might have to increase the held angle against the hones when sharpening in different portions of the edge grind.
 
He just found the weakness of that type of sharpening system, I assume it's rods or triangles that stand in a base?
To keep a consistent angle he needs to raise the handle as the edge bellys towards the tip. If not the edge from belly to tip will be more acute than the rest of the blade, that is once he forms a new angle there.
Opinals take a pretty quick turn in the last quarter or so of the blade, so it's not an easy thing.
 
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