Hapstone R2 Uneven Bevels

[crn3371]

I’m new to sharpening and have the Hapstone R2 with the angled clamps. What I’ve noticed on the last couple of knives is that I’m getting uneven edge bevels, one side has a wider edge than the other. Is this because of ffg blades? I’m trying to clamp on a square cut part of the tang where possible. Is this just to be expected with ffg blades? Besides cosmetics, does it really matter? Thanks.

 

[000Robert]

Are you using a digital angle cube to check your angles with?

 

[crn3371]

I’m using an angle cube, but only to check the initial angle on one side. Should I check both sides and adjust clamps as needed?

 

[cudgee]

I’m getting uneven edge bevels, one side has a wider edge than the other.

Normally that is 2 things. The bevels came uneven from the factory, and you are just repeating their mistake, or your angles are not the same in the sharpeners blade holder. EG. one side is 17deg, the other side is 21deg.

 

[000Robert]

I’m using an angle cube, but only to check the initial angle on one side. Should I check both sides and adjust clamps as needed?

I've never used a Hapstone system, but yes, anytime you move the clamp, or move the blade in the clamp, you should recheck the angle with your angle cube. I recheck my angles even when changing stones.

 

[Old Biker]

Also you may need to read this article and adjust your machine.

O.B.

 

[sickpuppy1]

It’s possible to have knife in the clamp slightly off also. That would cause the e even angles

 

[yoko]

I also have an r2 and had the same issue

I use my angle cube on both sides and adjust each flip

Since I've done that I have had 0 bevel problems!

(I have notice my ffg blades can sit more one way or the other, you can initially get your angle even on both sides before you fully tighten your clamps too)

 

[kreisler]

and adjust each flip

i'd do that too!
that's the only way to get even beveles

 

[scottc3]

Also you may need to read this article and adjust your machine.

O.B.

good detail and methods in Gritomatic's article, that can be applied to any clamping kit. Thx for the reference-

 

[crn3371]

+1 on the article! Got it pinned to my Home Screen for quick reference. Although I understand the process of adjusting the angle every time you flip the knife, I couldn’t imagine doing that on a reprofile, much rather get it clamped accurately to begin with. I also like what they said at the end of the article - “Don’t waste a lot of time to completely eliminate the angle difference. It does not affect the consistency of the sharpening.”

 

[777 Edge]

I’m new to sharpening and have the Hapstone R2 with the angled clamps. What I’ve noticed on the last couple of knives is that I’m getting uneven edge bevels, one side has a wider edge than the other. Is this because of ffg blades? I’m trying to clamp on a square cut part of the tang where possible. Is this just to be expected with ffg blades? Besides cosmetics, does it really matter? Thanks.

cudgee is almost there to hit the nail on the head for you with what he said about the factory grind. Not necessarily only because one side may have a different angle, as ground from the factory, but more likely because the edge is not in the center of the blade.

Imagine for a moment a tall rectangle with its top cut off on both sides to form a point. You can easily cut both sides of the rectangle at exactly the same angle, but you can cut one side off smaller than the other side. To form the point, you now cut the other side of the rectangle off at the same angle as the first small offcut, but a much bigger section. The top of your original rectangle can still have a perfect point with (for example) 15 degrees on both sides, but that point can be almost completely to one side.

Think of how a chisel is ground as an example of this done on purpose. All ground on one side, and the edge is completely off to the one side. You would want that type of grind in a chisel, but not necessarily on your favorite EDC knife.

Most knives, as they come ground from the factory, have extremely inconsistent and uneven bevels. It's definitely not an issue with your Hapstone system at all. The incredibly slight change in angle measured when you flip your rotating clamp over will NOT make any real significant difference at all. Don't measure and re-adjust the sharpening angle every time you flip the blade. This is NOT going to solve your problem at all. By doing that, you will be chasing your tail in circles and you won't get as good of an end result. DO measure your angle on the same side of the blade every time you swap stones, but NOT every time you flip sides.

BTW, you are clamping your FFG blade correctly by using the flat tang area for one clamp. This is the best way, keep doing it that way.

What you need to do to solve your problem, is spend a lot more time with your low grit stone to grind the smaller bevel further back, until it is about the same size as the bevel with the bigger side. This will then bring your edge into alignment with the center of the blade, with even bevels on both sides.

FYI, it's actually also a very common mistake a lot of guys make when they spend too much time re-profiling one side of a blade alone until they feel the burr on the opposite side, then when they finally start reprofiling the other side, the edge is ground out of alignment with the center of the blade. That's why (if you do it incorrectly), you could sometimes get the burr on one side much quicker than the other side when you re-profile a factory edge.

I suggest spending a good amount of time re-profiling and aligning your edge with the bevels ground visually the same on both sides. When you do this, don't be hasty when you feel a big burr forming, just keep going until your bevel is even, then continue sharpening normally after this. This will solve your problem.

 

[000Robert]

Most knives, as they come ground from the factory, have extremely inconsistent and uneven bevels.

I disagree unless you're buying gas station knives. Most edges that I have seen on knives that I buy are pretty even. I just assume that a dry belt was used on them and reprofile the edges to make sure the edges are on some good steel.

 

[777 Edge]

I disagree unless you're buying gas station knives. Most edges that I have seen on knives that I buy are pretty even. I just assume that a dry belt was used on them and reprofile the edges to make sure the edges are on some good steel.

It all depends on one's own standards of what one regards as "pretty even". Even the most expensive sought after factory knives I sharpen, have quite uneven edge bevels before I re-profile them. Won't mention any brands here, but they pretty much all suffer from the same issue.

It is true that it won't necessarily affect the sharpness of the blade in all cases, and also true that most people don't care about it too much or even visually see the uneven edge bevels but for the ones of us who are obsessed with edges, it just won't do.

 

[000Robert]

It all depends on one's own standards of what one regards as "pretty even". Even the most expensive sought after factory knives I sharpen, have quite uneven edge bevels before I re-profile them. Won't mention any brands here, but they pretty much all suffer from the same issue.

It is true that it won't necessarily affect the sharpness of the blade in all cases, and also true that most people don't care about it too much or even visually see the uneven edge bevels but for the ones of us who are obsessed with edges, it just won't do.

Except for Carothers Performance Knives, when I buy a knife, I already know that I'm going to reprofile the edges as soon as it gets here. Unless it's real sharp and the edges don't look too bad. Then I might wait until it needs sharpened.

 

[crn3371]

OP here. I’ve read everyone’s suggestions, and set up the R2 per the linked article from Gritomatic and it’s within their recommended specs. Most times there’s about a 1° angle difference between sides when I flip the knives and I’m assuming that’s clamping error dealing with ffg blades. On the occasions where I have that much difference between sides I’m adjusting arm angle every time I flip, using the angle cube to assure both sides are sharpened at the same angle. Even doing this I’m ending up with the bevel on one side being wider than the other. Now, I’m to the point that I really don’t care as the end result is satisfyingly sharp knives. But, my analytical side still would like to know why this is still happening.

 

[777 Edge]

OP here. I’ve read everyone’s suggestions, and set up the R2 per the linked article from Gritomatic and it’s within their recommended specs. Most times there’s about a 1° angle difference between sides when I flip the knives and I’m assuming that’s clamping error dealing with ffg blades. On the occasions where I have that much difference between sides I’m adjusting arm angle every time I flip, using the angle cube to assure both sides are sharpened at the same angle. Even doing this I’m ending up with the bevel on one side being wider than the other. Now, I’m to the point that I really don’t care as the end result is satisfyingly sharp knives. But, my analytical side still would like to know why this is still happening.

Adjusting the angle every time you flip is not necessary, and in fact can be counter productive. Until you've evened out the edge bevel, don't be too obsessed with chasing the angle both sides. Just spend a lot more time on the narrow bevel side to grind it away more. Try to "forget" about the wide edge bevel side for now, and just spend some good time grinding away the narrow edge bevel until it visually matches what you want.

FYI as a side note, a difference of 1 degree as measured from one side to the other won't be visible at all on your edge, and won't affect your sharpening. What IS visible on the edge bevels, is if the edge is not aligned with the center of the blade.

For a blade sharpened at 15 degrees per side, vs 16 degrees per side (assuming as an example a thickness behind the edge of 0.2 inch), the difference in edge bevel length will only be 0.0023 inch. That's about the diameter of a strand of hair. Obviously not perceptible with the naked eye.

As you can see from the math, a 1 degree difference from side to side is negligible to the edge bevel, assuming it is aligned with the center of the blade.

Have a read again in my post #12 above.

 

[cudgee]

But, my analytical side still would like to know why this is still happening.

Understandable.

Just spend a lot more time on the narrow bevel side to grind it away more. Try to "forget" about the wide edge bevel side for now, and just spend some good time grinding away the narrow edge bevel until it visually matches what you want.

This is good information. Start on the side with the narrower bevel till a burr forms along the length of the blade, then repeat on the other[ thicker bevel ] side. This will take far fewer strokes, so the bevel will eventually even out, just start on the narrower bevel till this happens every time you sharpen the knife. Also, when you achieve even bevels, whenever you sharpen the knife start on alternating sides each time, it takes longer to get a burr on your first side, if you do alternate sides this will keep the bevels even.

 

[crn3371]

Thanks again everyone. Nice to know there’s no need to adjust angle every time I flip, doable without the fine tuning adapter, but still a pita. I’ll try starting on the side with the narrower bevel and see how that works out. Ultimately it’s more cosmetics than anything as the end result is still a sharp knife.

 

[cudgee]

Thanks again everyone. Nice to know there’s no need to adjust angle every time I flip, doable without the fine tuning adapter, but still a pita. I’ll try starting on the side with the narrower bevel and see how that works out. Ultimately it’s more cosmetics than anything as the end result is still a sharp knife.

Let us know how things go.