Wicked Edge / Edge Pro

[singularity35]

1. Set the angle desired
2. Put Blade on the table, on the Hilt, that's the flat spot of the blade by the handle
3. Carefully make a flat spot on the edge with light passes until a burr is formed
4. Mark the Flat spot with a sharpie
5. Adjust the angle up
6. Put the blade back on the table with the edge flat now
7. Test the angle and adjust as needed until the sharpie mark is gone
8. Now the angle is set correctly and you can sharpen at the correct angle.

Thanks!

 

[clayallison]

The bevel cross section still increases towards the tip. Either way it's ugly and it looks unprofessional.

I'm trying to visualize why that is. Can it really keep the same angle? Or is it bisecting at a more acute angle to produce a larger cross-section? As mentioned, it may also be the thicker steel at the tip. I'm guess a combination of thicker steel and a more acute angle. Dammit, I'm trying to think of it mathematically- it's a plane (sharpening stone) bisecting an object. Sort of like how a cone can be bisected by a plane to produce either a circle, ellipse, parabola, or even a triangle.

The answer has to do with the curvature of the blade. On an entirely straight blade with no thickening, the angle and cross section remain constant out to any distance. The more curvature there is, the more the effect you're describing will be exaggerated. In the WE, you would correct for it by clamping the knife off center, closer to the tip. The angle remains constant along the straight portion of the blade so it doesn't matter how far back you clamp the knife. I can post some images tomorrow when I've got my camera up and running. For the EP, you would move the tip over the center of the table. you have to rotate the handle away from yourself so that the edge of the blade stays at the same distance from the pivot point.

 

[Medic1210]

The bevel cross section still increases towards the tip. Either way it's ugly and it looks unprofessional.

I'm trying to visualize why that is. Can it really keep the same angle? Or is it bisecting at a more acute angle to produce a larger cross-section? As mentioned, it may also be the thicker steel at the tip. I'm guess a combination of thicker steel and a more acute angle. Dammit, I'm trying to think of it mathematically- it's a plane (sharpening stone) bisecting an object. Sort of like how a cone can be bisected by a plane to produce either a circle, ellipse, parabola, or even a triangle.

Have you not seen the photo of the BM710 posted early in the thread? It was done on the EP, and it has a wider bevel near the tip as has already been explained in this thread.

 

[Medic1210]

We need to get some videos of W.E. sharpened knives cutting things, come on people .

Have you even looked at any of the videos I've linked to? One shows him ruin a Chef's knife edge with a bastard file, and restoring it to razor sharp, slicing paper and a soft tomato in less than 5 minutes, and another shows him sharpening a CCK cleaver, and slicing the thinnest slices of carrot and tomato I've ever seen. Other videos shows him shaving his face with a hunting knife, and another shows him sharpening a Sushi chef's knife, followed by the chef slicing fish. There are videos out there if you look.

Oh, and looking at the W.E. design- It actually does look like it has continuously variable angles- or at the vary least it appears you can choose half-degrees if you don't screw down the angle guide into the pre-drilled holes? Anyone want to weigh in on that?

You are correct. Not only can you change the angles by degree, you can tighten the rod down at any point you want on the guide. If you have a digital angle gauge, or an iPod touch (Tilt Meter is a great app), you can set it to any angle you want.

 

[ricklee4570]

In theory, you would think that trying to pivot the Edge Pro to keep the edge parallel in the center of the table would be hard to accuratly duplicate for perfect edges. Especially since you remove the knife and turn it over after every swipe of the stone.

With that said, it doesn't seem to matter. I have purposely moved the tip at slightly different parts of the table and the edged seem just as sharp. My guess is the slight variations are so minor as not to really matter.

 

[ricklee4570]

My previous post should read "pivot the knife on the table of the Edge Pro", not pivot the Edge Pro. My computer wouldn't let me edit that for some reason!

 

[fockewul]

The answer has to do with the curvature of the blade. On an entirely straight blade with no thickening, the angle and cross section remain constant out to any distance. The more curvature there is, the more the effect you're describing will be exaggerated.

I believe your explanation is correct and it makes perfect sense.

For the EP, you would move the tip over the center of the table. you have to rotate the handle away from yourself so that the edge of the blade stays at the same distance from the pivot point.

That is what I said before, but you worded it better than I did :thumbup:

Having said this and having watched the WE video where an angle gauge clearly demonstrates that the angle remains constant, I believe that this "angle variation" problem about guided systems is a false one. What actually occurs is a widening of the bevel due to the reasons explained above.

However, I'm having trouble understanding why should the WE be any different than other guided systems in this regard. The fact that the knife is clampled vertically changes none of the geometrical principles that rule guided systems of the WE, EP, Lansky, DTM Aligner, etc. sort.

 

[cbwx34]

However, I'm having trouble understanding why should the WE be any different that other guided systems in this regard. The fact that the knife is clampled vertically changes none of the geometrical principles that rule guided systems of the WE, EP, Lansky, DTM Aligner, etc. sort.

That's just it, (if I understand your question) it doesn't. I used to think this too, until someone pointed it out on the Lansky, that where the clamp is positioned doesn't change the angle, it only changes as it moves around the curve.

Also, you can't exactly include the EP in this, since the blade can be moved during sharpening (unless of course you're holding it in one position).

cbw

 

[BladeChemist]

Medic1210

I'm not talking about the videos the manufacturers made to sell their system, I'm talking about user-submitted reviews and videos of either the system being used or more importantly- images and cutting tests of the resulting blade edge. You and others in this thread have purchased the system so I was hoping someone would demonstrate how it performs. This isn't a malicious request- I'm genuinely curious about, for instance, what grit begins to produce what cutting effect. What do the bevels look like for a variety of blades? If you've already purchased the W.E., would you recommend buying the strops for it right off the bat as I assume they're needed for the finest edge possible?

E.P./W.E. bevel increase

For the E.P. I believe this is only applicable for knives where the blade is thicker near the tip-bevel than the rest of the knife. Used properly, the E.P. will have no problem putting a perfect bevel on the curved portion of a uniform ground blade- Ankerson's images demonstrate that with the Spydercos. The W.E. will have the same problem with blades that are thicker at the tip, but the effect will be compounded by the design of the system.

Explanation:

Sometimes, if one wishes to convince themselves an effect is real you have to imagine an impossible scenario (bear with me here ). Imagine a blade one mile long clamped to the W.E. with a one mile long guide-rod to match. Moving out near the tip the stone and guide-rod are practically parallel with the blade and the bevel in effect is the blade. That would also mean the resulting edge is being sharpened at a very tiny inclusive angle.

Throw that scenario away and imagine a normal long-bladed knife in the W.E. The bevel will still increase near the tip and the inclusive angle will be smaller, but as someone already mentioned the effect isn't very large. But that's still a counterpoint to clayallison's claim that the angle and bevel remain unchanged for straight-edged knives out to any distance.

I'm still trying to imagine the curved-blade effect on the bevel and angle. Does that mean if you sharpen a long blade with a thick curved tip the resulting bevel will be widened by three different factors?

Maybe that's the ultimate nemesis of the W.E. system- a long bendy FFG blade with a thick curved tip. The resulting blade would look like it was sharpened by a highly caffeinated funhouse clown .

 

[clayallison]

Medic1210

I'm not talking about the videos the manufacturers made to sell their system, I'm talking about user-submitted reviews and videos of either the system being used or more importantly- images and cutting tests of the resulting blade edge. You and others in this thread have purchased the system so I was hoping someone would demonstrate how it performs. This isn't a malicious request- I'm genuinely curious about, for instance, what grit begins to produce what cutting effect. What do the bevels look like for a variety of blades? If you've already purchased the W.E., would you recommend buying the strops for it right off the bat as I assume they're needed for the finest edge possible?

E.P./W.E. bevel increase

For the E.P. I believe this is only applicable for knives where the blade is thicker near the tip-bevel than the rest of the knife. Used properly, the E.P. will have no problem putting a perfect bevel on the curved portion of a uniform ground blade- Ankerson's images demonstrate that with the Spydercos. The W.E. will have the same problem with blades that are thicker at the tip, but the effect will be compounded by the design of the system.

Explanation:

Sometimes, if one wishes to convince themselves an effect is real you have to imagine an impossible scenario (bear with me here ). Imagine a blade one mile long clamped to the W.E. with a one mile long guide-rod to match. Moving out near the tip the stone and guide-rod are practically parallel with the blade and the bevel in effect is the blade. That would also mean the resulting edge is being sharpened at a very tiny inclusive angle.

Throw that scenario away and imagine a normal long-bladed knife in the W.E. The bevel will still increase near the tip and the inclusive angle will be smaller, but as someone already mentioned the effect isn't very large. But that's still a counterpoint to clayallison's claim that the angle and bevel remain unchanged for straight-edged knives out to any distance.

I'm still trying to imagine the curved-blade effect on the bevel and angle. Does that mean if you sharpen a long blade with a thick curved tip the resulting bevel will be widened by three different factors?

Maybe that's the ultimate nemesis of the W.E. system- a long bendy FFG blade with a thick curved tip. The resulting blade would look like it was sharpened by a highly caffeinated funhouse clown .

Though it's counterintuitive, the angle really does remain constant along the straight line, owing to the fact that the plane of the stone against the blade remains constant without regard to the distance from the pivot point. Consider the following diagrams:

http://4.bp.blogspot.com/_mxfsoGTLz...AMY/rknOSPdzJWM/s320/Constant+Angle-+pt+7.png

Look at the two identical triangles and imagine the plane that exists along the line of their hypotenuses - that is the plane along which the sharpening stone travels respective to the knife.

Below you can see how, by moving the blade back in the clamp so that the tip is closer to the pivot point, you can substantially mitigate the effect caused by the curvature:

The angle is getting a little more narrow toward the heel as the blade widens and the edge rises slightly higher above the pivot point. Rotating the blade to level it would reduce that effect if desired.

 

[clayallison]

Medic1210

I'm not talking about the videos the manufacturers made to sell their system, I'm talking about user-submitted reviews and videos of either the system being used or more importantly- images and cutting tests of the resulting blade edge. You and others in this thread have purchased the system so I was hoping someone would demonstrate how it performs. This isn't a malicious request- I'm genuinely curious about, for instance, what grit begins to produce what cutting effect. What do the bevels look like for a variety of blades? If you've already purchased the W.E., would you recommend buying the strops for it right off the bat as I assume they're needed for the finest edge possible?

E.P./W.E. bevel increase

For the E.P. I believe this is only applicable for knives where the blade is thicker near the tip-bevel than the rest of the knife. Used properly, the E.P. will have no problem putting a perfect bevel on the curved portion of a uniform ground blade- Ankerson's images demonstrate that with the Spydercos. The W.E. will have the same problem with blades that are thicker at the tip, but the effect will be compounded by the design of the system.

Explanation:

Sometimes, if one wishes to convince themselves an effect is real you have to imagine an impossible scenario (bear with me here ). Imagine a blade one mile long clamped to the W.E. with a one mile long guide-rod to match. Moving out near the tip the stone and guide-rod are practically parallel with the blade and the bevel in effect is the blade. That would also mean the resulting edge is being sharpened at a very tiny inclusive angle.

Throw that scenario away and imagine a normal long-bladed knife in the W.E. The bevel will still increase near the tip and the inclusive angle will be smaller, but as someone already mentioned the effect isn't very large. But that's still a counterpoint to clayallison's claim that the angle and bevel remain unchanged for straight-edged knives out to any distance.

I'm still trying to imagine the curved-blade effect on the bevel and angle. Does that mean if you sharpen a long blade with a thick curved tip the resulting bevel will be widened by three different factors?

Maybe that's the ultimate nemesis of the W.E. system- a long bendy FFG blade with a thick curved tip. The resulting blade would look like it was sharpened by a highly caffeinated funhouse clown .

You got me very curious about the effects of curvature and thickening in relation to bevel cross section. On my CR Umnumzaan, the widening bevel is apparent to the eye though the angle remains approximately constant (+/- .2°.) I measured the thickness at the shoulder of the bevel at the heel and in the curve toward the tip. The blade thickness toward the heel is 0.024". Toward the tip on the curve it is 0.054" thick. Without compensating for the curvature by mounting the blade further back in the clamp, you would be dealing with both factors for bevel widening; curvature effect and blade thickening.

 

[ricklee4570]

We appreciate your participation in this thread Clay. Thanks for the information!

 

[hardheart]

here is why knives thicken near the tip
[youtube]XkZuO1LDfOk[/youtube]
This is by a custom maker, but industrial automatic grinding machine aren't going to follow blade profiles either. Since the edge turns up as it approaches the tip, it is in a thicker part of the grind. Without a distal taper, the tip is thicker. That has nothing to do with sharpening equipment. But, to keep the bevel even along the edge, yes, the angle must increase closer to the tip. Sharpening at a consistent angle then widens the bevel - just like if you send a knife to a maker for a regrind, and the primary grind gets wider.

The length of the rod is going to change the angle, and the length from the pivot to the edge changes as the blade sweeps around the belly and as you get farther from the center of the clamp or Edgepro base. If at any point the stone contacts the edge at a point closer or further from where you set it, then the angle will be different. The difference in that distance will directly affect the sharpening angle.

I think this has been covered well, a little too well really.

 

[BladeChemist]

Though it's counterintuitive, the angle really does remain constant along the straight line, owing to the fact that the plane of the stone against the blade remains constant without regard to the distance from the pivot point. Consider the following diagrams:

http://4.bp.blogspot.com/_mxfsoGTLz...AMY/rknOSPdzJWM/s320/Constant+Angle-+pt+7.png

Look at the two identical triangles and imagine the plane that exists along the line of their hypotenuses - that is the plane along which the sharpening stone travels respective to the knife.

Below you can see how, by moving the blade back in the clamp so that the tip is closer to the pivot point, you can substantially mitigate the effect caused by the curvature:

The angle is getting a little more narrow toward the heel as the blade widens and the edge rises slightly higher above the pivot point. Rotating the blade to level it would reduce that effect if desired.

Your drawings are misleading. You're not taking into account that your vector (guide rod) is 3-dimensional and the 2-d component normal to the edge decreases as you move towards the tip. Redraw the image looking down the blade and take into account the changing vector and only then should you apply trig and solve for the sharpening angle. It kind of looks like you were naughty and made a CAD drawing and had it read the same angle from two identical triangles .

When in doubt reread the "extreme" example I wrote in my last post to convince yourself. The bevel increases and sharpening angle decreases as you move toward the tip. We can't move on to discussing the consequence of this effect if we can't agree on the reality of the W.E.'s design.

 

[hardheart]

if the lines are the same length, the sharpening angle is the same. move the knife in the clamp

 

[BladeChemist]

if the lines are the same length, the sharpening angle is the same. move the knife in the clamp

No. You drew 2-d lines on an obviously 3-d perspective image. I want desperately to convince you this is incorrect- that the angle and bevel have to change because of the design of the system. Yes, the effect is small for shorter knives but it does exist and should not be ignored. You're an experienced member here so it worries me that others will choose to draw their conclusions based on postcount or reputation.

 

[hardheart]

No, the angle and bevel do not have to change. You can reposition the guide rod pivot, or move the blade in the clamp. The angle can be maintained, it is just a matter of it being worth the hassle. There is a 2D image at work here, the right triangle created from the vertical plane the blade is on, the hypotenuse of guide rod and stone, and the distance from the base to the guide rod pivot. One angle is going to stay the same, but you can change the other two angles and the length of any of the legs just how I said - by moving the blade, or even changing the pivot position. The triangle does not merely shift left or right, it rotates about the leg of the graduated bar of the device. So like I've said several times, you'd have to move the knife so the tip is exactly along the arc created as the stone is laid over - without moving the stone in or out and thereby changing the angle created between the surface of the stone and the centerline of the blade.

Somehow, I haven't lost grasp of the fact that knives are three dimensional objects.

 

[stitchawl]

No, the angle and bevel do not have to change. You can reposition the guide rod pivot, or move the blade in the clamp.

I have a feeling that that point is where people are having difficulties. Those saying the bevel can remain the same are moving or adjusting something. Those saying the bevel with change are not.

In order to maintain the same angle, something has to be changed, be it the blade position or the guide rod pivot. Keeping the blade locked in and not moving the guide rod pivot position will result in an increasing angle as the contact point moves further away laterally from the pivot point.


Stitchawl

 

[hardheart]

Well, to me, the point is that for everything else, you move/adjust something anyway. If the blade is long or the belly very deep, you reposition it on the Edgepro when you approach the tip. If the blade isn't a wharncliffe of sheepsfoot, you adjust your wrist relative to the stone when freehanding. There's no reason to not reposition the blade in a Wicked Edge, and the fact that the angle will change if you don't change some other measure is pretty basic to all sharpening methods.

 

[BladeChemist]

No, the angle and bevel do not have to change. You can reposition the guide rod pivot, or move the blade in the clamp. The angle can be maintained, it is just a matter of it being worth the hassle. There is a 2D image at work here, the right triangle created from the vertical plane the blade is on, the hypotenuse of guide rod and stone, and the distance from the base to the guide rod pivot. One angle is going to stay the same, but you can change the other two angles and the length of any of the legs just how I said - by moving the blade, or even changing the pivot position. The triangle does not merely shift left or right, it rotates about the leg of the graduated bar of the device. So like I've said several times, you'd have to move the knife so the tip is exactly along the arc created as the stone is laid over - without moving the stone in or out and thereby changing the angle created between the surface of the stone and the centerline of the blade.

Somehow, I haven't lost grasp of the fact that knives are three dimensional objects.

If what you're saying is that the W.E. can be used essentially as an E.P. to maintain an exact angle and bevel by continuously repositioning the blade and reclamping you would be correct- but I believe it's a very disingenuous thing to emphasize. One of the high-points of the system and one that is clearly marketed by the manufacturer and commented on by owners in other threads is the ability to keep the blade firmly clamped. This allows for the very rapid 'speed demon' nature of this system to work its magic by flipping the stones to a different grit or quickly sliding on and off a new stone set. It has also been mentioned that a log of how the blade was previously clamped would allow one to rapidly reclamp and resharpen the blade as it had been done before and in what looks like an exacting manner. If the point you were trying to make was that the W.E. can technically be used in a manner to nullify some of its design disadvantages then I have no disagreement with you, and I was most certainly not questioning your ability to understand that knives have more than two physical dimensions.

However, I'm still not sure if you're correctly understanding the point I've been trying to make, and if I could ask one thing of you it would be to explain why the previously described 'one mile long knife/guide rod' example is false. I believe it's very clear that the system as it stands produces an edge whose angle becomes lower and bevel becomes larger as it nears the tip- but that the effect isn't necessarily significant.

I also plan on contacting the company and explaining my stance regarding their claim, posted on their website, that the system produces an edge whose angle "...does not change along the length of the blade". It appears their claim was based not on the fundamentals of the system but on some rather shaky testing (pictured on the same page). Thus it is technically misleading and I believe they should clarify what they mean. Before anyone jumps on me for doing that, I just want to share one of my recent thoughts that I believe this system (and I won't say this lightly) will revolutionize the knife world. Not because it's based on any revolutionary type of sharpening, but because its very straightforward/user friendly/high performance and high speed nature is going to get a lot of people who wouldn't otherwise purchase a high-end system involved in sharpening knives, and that is a very, very good thing. It's going to get more people interested in sharpening, more sharp knives in people's kitchens and pockets, and heck I hope it gets the E.P.'s inventor Ben to sell a larger variety of more affordable diamond stones. And for all its worth the company could or maybe should just as well claim that the system produces an edge that "get's slightly sharper towards the tip".