Knives that are difficult to sharpen?

T

TN Jack

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Nov 10, 2018
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Any one ever have a knife that is really difficult to sharpen? I have 3 that are really testing my patience. I have tried the Lansky sharpening system, a Smith quick sharpener, and an old school Arkansas stone. None seem to work on 2 Case knives and 1 Bear and Son knife. Maybe those knives are just duds?
 
Whenever i have that happen (more often than id admit) i slow down and go back to basics and my coarse stone. Raise a good burr along the whole edge then flip it a few times and then move up the grits and finish on a strop.
 
I had a Winchester Black Box knife that seemed to have a monstrously hard set of blades. Even on a course 300 grit diamond sharpener, the blade felt like it just skated across the stone. It finally took an edge, but it literally took 4 times as long as any other knife I remember.
 
Either your not getting a clean apex on the edge or the knife is too soft.

I have a Bear and Sons trapper that won’t take an edge. It just flops back and forth and eventually breaks off.

All my Case knives seem fine though.
 
A knife can be hard to sharpen for many reasons. It can be due to the blade and edge geometry and steel type and also be hard because of what the person sharpening is doing. Those are just a few examples.

Knowing these makers I would assume the knives in question have steel with easy grindability so we should be able to eliminate that as an issue. What approximate angle are you sharpening at, and approximately how much force are you using? Are you sharpening to a burr? Burrs are bad for a number of reasons so you want to minimize the amount of burr you raise to as little as possible. Are you keeping the angle consistent? Is there light reflecting from the edge when you look at it straight on?
 
TheChunk91 said:
A knife can be hard to sharpen for many reasons. It can be due to the blade and edge geometry and steel type and also be hard because of what the person sharpening is doing. Those are just a few examples.

Knowing these makers I would assume the knives in question have steel with easy grindability so we should be able to eliminate that as an issue. What approximate angle are you sharpening at, and approximately how much force are you using? Are you sharpening to a burr? Burrs are bad for a number of reasons so you want to minimize the amount of burr you raise to as little as possible. Are you keeping the angle consistent? Is there light reflecting from the edge when you look at it straight on?
Click to expand...

I take serious exception to the statement that burrs are bad.

You sure do not want a burr on the edge when it is time to use it, BUT, the failure to get a burr on the entire edge on first one side and then the other is the single most frequent reason that people do not get knives really sharp.
If a burr is not raised ALONG THE ENTIRE EDGE, you have not ground down to the edge. The burr is your indicator that you are done on that side of the blade - remember along the ENTIRE edge, not just at one spot on the edge.

Then, and only then, sharpen to a burr on the other side.

Repeat until you have used the finest stone you will use. (Actually you really don't need anything finer than a Norton India stone - about 800grit - to get a shaving sharp edge.) Then with light strokes, and maintaining your sharpening angle, do several strokes on each side, until no or at least very little burr can be felt.

Then strop. Easiest strop to make - denim stuck down with double sided carpet tape, dressed with green or white stropping compound (very best - Rick's White Lightnin' - Google it)

DO NOT flip the knife at the end of every stropping stroke. If you do, you will anticipate that flip, and be dragging your edge at too steep of an angle towards the end of it, and thereby wreck the edge (I have seen dozens - maybe hundreds of people strop incorrectly).
Don't flip it at all. Just give it 20 firm strokes on one side being absolutely fanatical about maintaining the sharpening angle throughout the entire stroke, the repeat going the other way. Back to the first side 20 more, and the other side 20 more.

I have taught 100s of people from 9yrs old to about 90 to get edges that they could literally shave with following this procedure.

Do not be afraid that you will ruin the knife doing this. You will not, and even if you did, but learned to sharpen in the process, it would be worth it.
 
Mr. Chips said:
I take serious exception to the statement that burrs are bad.

You sure do not want a burr on the edge when it is time to use it, BUT, the failure to get a burr on the entire edge on first one side and then the other is the single most frequent reason that people do not get knives really sharp.
If a burr is not raised ALONG THE ENTIRE EDGE, you have not ground down to the edge. The burr is your indicator that you are done on that side of the blade - remember along the ENTIRE edge, not just at one spot on the edge.

Then, and only then, sharpen to a burr on the other side.

Repeat until you have used the finest stone you will use. (Actually you really don't need anything finer than a Norton India stone - about 800grit - to get a shaving sharp edge.) Then with light strokes, and maintaining your sharpening angle, do several strokes on each side, until no or at least very little burr can be felt.

Then strop. Easiest strop to make - denim stuck down with double sided carpet tape, dressed with green or white stropping compound (very best - Rick's White Lightnin' - Google it)

DO NOT flip the knife at the end of every stropping stroke. If you do, you will anticipate that flip, and be dragging your edge at too steep of an angle towards the end of it, and thereby wreck the edge (I have seen dozens - maybe hundreds of people strop incorrectly).
Don't flip it at all. Just give it 20 firm strokes on one side being absolutely fanatical about maintaining the sharpening angle throughout the entire stroke, the repeat going the other way. Back to the first side 20 more, and the other side 20 more.

I have taught 100s of people from 9yrs old to about 90 to get edges that they could literally shave with following this procedure.

Do not be afraid that you will ruin the knife doing this. You will not, and even if you did, but learned to sharpen in the process, it would be worth it.
Click to expand...

They are bad because a burr is weakened steel that is a result of over sharpening to the point that the apex loses its strength, collapses and flops over. There is no reason to raise a large burr, it wastes steel and hurts edge retention.

Now there is no way to sharpen without raising a burr, it’s plain impossible, but my point is the degree of which it is raised can be controlled to the minimum. This is very important. You want to sharpen up to the point just before raising the burr, then increase the angle a few degrees and sharpen the microbevel with just one stroke on each side. This is the cleanest way to form an edge. It allows you to minimize the burr as much as you can possibly do so.

You don’t have to do any this to make a knife sharp and be useful, but it is definitely a better way for the lifespan and performance of the blade.
 
Well, we are in agreement.
It is impossible to really sharpen a knife without raising a burr, as you said.
And I agree, there is no point in an excessively large burr, BUT there are a lot of people who are trying and failing to get their knives sharp because they do not get the burr in the process. If you want to cut with your knife, it would be better to get a somewhat larger burr than is necessary, and then remove it by stone and stropping.

If you would rather just look at your knife, well then, by all means keep it pristine.
 
It's been a few days since I owned one ... 1965? 1966? :..
ONTARIO 499 "Jet Pilot Survival Knife" (Army/Navy surplus) was darn near impossible to get sharp.
The thick edge had a lot to do with that, of course. I never did get around to reprofiling the edge on that.

Pre -1999 Buck 110 with 440C blades and before the Edge 2000 edge geometry. Those were a pain in the sitter to sharpen using an Medium and hard Arkansas stone.
I sometimes wonder if the un-ease of sharpening the early 110's is what gave the Old Timer 7OT a place in the market.
The "Schrade Plus" 440A and the 1095 were a bunch easier to sharpen. (I'd guess they still are.)
 
Thanks for this thread. I rate my sharpening skills as pretty good, and I can get most knives shaving sharp, but my Mundial kitchen knives never want to play the game. I also have a Sabatier carving knife that laughs at my attempts to sharpen it. No idea what I am doing wrong - its exacerbating. I might go with the coarser stone approach.
 
Some steels are harder to sharpen, whether they need diamond stones or just a lot of patience.
Recurved edges are also not my favorite to freehand.
 
I know exactly what is wrong. The factory blade grinds! They are too thick and probably uneven. You need to use your Lansky coarse stone and reprofile them to a consistent and better angle. Use a Sharpie or magic marker on the edge so you can see where the stones are grinding.
 
AndreLinoge: You made me smile. A very true statement. :)

Sometimes it just happens that you get a weird blade. You'll work your way into a good edge most times. But I do have fairly high quality knives (GEC #68 especially) where the difference is remarkable between identical looking knives. I have one that is a chore to sharpen and one that just takes an edge easily and has a higher edge quality.

It happens. And it is hard to explain sometimes.

Good luck,
Will
 
Get yourself a Norton JB8 and a Sharpie.

Start course, get an apex and a sharp edge or any higher grit is moot. I love my Arkansas stones but they are for honing that actual sharpening. I keep up with my kitchen knives so I get away with just taking them to a soft but that's because I've already profiled and apexed them on a course stone.

These days I rarely use higher grits. I tend to live in the 300-600 grit range. But the point is, you have to have a sharp edge off the course stone. You can wrap some paper around the stone and strop on that when you're done. For these steels it should be enough to remove the burr.
 
TheChunk91 said:
Now there is no way to sharpen without raising a burr, it’s plain impossible
Click to expand...
Hey there,
Along this point, I recently watched a sharpening video that stated a burr is only produced when sharpening "away" from the edge. That is referring to the direction one uses with passes on a stone-- towards or away from the edge.

I don't have much sharpening experience outside of ceramic rods, but I was intrigued by watching this. I was also under the impression that a burr was a key step in getting a good edge. This states that sharpening "towards" the edge produces no burr ??

Worth a look.

 
I have two hawkbills that I cannot sharpen for the life of me. Only two knives I have never been able to sharpen
 
Pinemoon said:
Hey there,
Along this point, I recently watched a sharpening video that stated a burr is only produced when sharpening "away" from the edge. That is referring to the direction one uses with passes on a stone-- towards or away from the edge.

I don't have much sharpening experience outside of ceramic rods, but I was intrigued by watching this. I was also under the impression that a burr was a key step in getting a good edge. This states that sharpening "towards" the edge produces no burr ??

Worth a look.

Click to expand...

Due to the fact that he is sharpening towards the edge and alternating sides, burr formation will be minimal but not eliminated.

If you sharpen one side at a time, either towards or against the edge, you will form a more substantial burr than if you alternated sides.

I think this is beneficial because it allows you to see and feel that the burr is consistent along the edge before moving to the other side. Either method works though.
 
Super steels drive me crazy. I have a Syderco PM2 in S30V and Buck 110 in S35VN. I thought these knives would never get sharp. I was use to D2, 1095, O1 ect. It takes forever to get through the edge the first time with super steels. They also do not feel as sharp when they are really sharp. D2, 1095 and O1 feel razor sharp when they are sharp. The new powder steels do not feel sharp, yet they cut like crazy. That's my experience anyway. I am a knife user so I do like more traditional steels that are easy to sharpen in the field.
 
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