Serration idea/question

[Evil D]

I'm trying to wrap my mind around something that seems like it should have a simple answer, but I just can't intellectualize this. Serrations are always chisel cut. This leads to having the edge off to one side of the center line of the blade, and thus as a chisel grind cuts they tend to "walk" through a cut, such as when cutting through cardboard.

So my question is, is there a way to grind the serrations and/or blade in such a way that the V of those serrations ends up being centered as a plain edge blade would be, to avoid this behavior? Seems like you could change the grind of the blade, maybe instead of grinding a standard V flat grind with the center line of the blade being right in the middle, you would grind it offset towards the side that the serrations will be cut on. Wouldn't this result in a more centered edge? If so why doesn't anyone grind a serrated blade this way?

[Bugout Bill]

I'm pretty sure this is how Chris Reeve's serrations work.

[spyderHS08]

I' have owned probably a couple hundred knives in my time and I've never seen this. However the way you say it does make it seem obtainable. But I'm guessing it is much easier and more cost efficient to do serrations with a chisel grind. I think there are some custom knives out there like this but I'm willing to bet they're few and far in between. It would be cool to see though as I have personally experienced the walking of the blade when cutting heavy plastic and cardboard. It would be nice to hear an answer from the big guy as to why they're ground this way.

[Evil D]

Well, the serrations would still be chisel cut, but the offset grind of the blade itself would (I think) move the center line of the blade itself over to one side enough that the offset of the chisel grind would land the edge in the center as opposed to off to the side like the usually are.

[Surfingringo]

I would imagine the "walking" is much more a product shape of the grind itself than it's centering. I could be wrong but I believe that regardless of centering, a chisel grind will always pull to the flat side; same as an actual chisel. I don't have an issue with it in real world use but i don't tend to cut things like cardboard where this behavior probably becomes much more notable. If I put my mind to looking for a solution, all I can come up with is grinding from both sides which I'd imagine is a good bit more complicated when it comes to serrations.

[Evil D]

I would imagine the "walking" is much more a product shape of the grind itself than it's centering. I could be wrong but I believe that regardless of centering, a chisel grind will always pull to the flat side; same as an actual chisel. I don't have an issue with it in real world use but i don't tend to cut things like cardboard where this behavior probably becomes much more notable. If I put my mind to looking for a solution, all I can come up with is grinding from both sides which I'd imagine is a good bit more complicated when it comes to serrations.

Yeah, you're right the walking doesn't have to do with centering, it's the chisel grind. What I'm trying to imagine is less about centering and more about making the V of the chisel grind more "V like" in the way that a PE blade is. I'm just not sure it's even possible since the angle of the serrations is so steep that to offset it with the grind of the blade it would take an equally steep angle, which may not be possible.

I think in the end few people will care or give this as much thought as I have.

[Blerv]

I'm sure anything is possible. It's a matter if it's possible on a larger manufacturing scale. My best guess is the depth of the teeth might be different or the geometry wouldn't be similar.

Symmetry and graceful cutting has never been the draw of the SpyderEdge. In my limited experience I've yet to try a knife with that same bite even if their teeth were prettier. Given Spyderco's experience with the processing and their inclination to avoid chisel edges whenever possible...I would think they would have tried a different way by now. Then again, that's probably just lazy fanboy/shill delusion. :)

[Evil D]

Here's an idea....what if you took a blade that was chisel ground with the flat side on the left (as in the "spyder" side of the blade), and then you ground chisel cut serrations into that blade from the typical side. I wonder if that would be enough to center up the angle of the V?

[Fancier]

I have kitchen knives that are double cut serrated that cut straight, and others that are single cut serrated that tend to wander off opposite the bevel. Both are possible, and my double cut serrated knives aren't noticeably more expensive than my single cut ones. Obviously it takes more work to cut the serrations evenly from both sides. For single cut bevels I prefer to have the bevel on the right hand side.

[razorsharp]

I think I recall sal saying something about V serrations and them being rather difficult to do so they dont ... something like that

[paladin]

Double sided serrations would work better...

However, it would seem that it would be a tall order to grind a SpyderEdge on both sides ... with all the peaks & valleys indexing precisely on both sides...

Imprecise alignment would look pretty snaggletoothed, I imagine :eek:

I wonder if use would be adversely affected with an ugly, poorly aligned, double-sided grind? :confused:

Picture in your mind one side with SpyderEdge, the other side ground with the SpyderEdge with the two patterns indexed off by 50%...

Would it be a nightmare, or a SuperSerratedSpyderEdge? :eek: :spyder: :D Good thread!

[ChapmanPreferred]

As you sharpen your serrations on the 204 Triangle Sharpmaker, using equal strokes (1 to 1 ratio) you will effectively start to grind in a bevel on the non-ground side of the edge. This will also help to reduce/eliminate the "walk" during the cut.

[Evil D]

As you sharpen your serrations on the 204 Triangle Sharpmaker, using equal strokes (1 to 1 ratio) you will effectively start to grind in a bevel on the non-ground side of the edge. This will also help to reduce/eliminate the "walk" during the cut.

I've tried this on other knives, but I don't like that it cuts down so much on the points, which are usually the first thing to start wearing off when you start cutting a bevel on the back side. I can see how it would definitely help to center up the edge but it seems like it would also make your serrations much more shallow, which seems to me would also reduce their effectiveness.

[sal]

We've played around with a variety of serration shapes, sizes and angles. As Chapman stated, sharpening the serrations on both sides with a shapmaker reduces the "walk". On our kitchen knives, tlting the blade to the right wil also reduce the cutting curve in large objects.

We believe that what we're doing is the best balance for performance, cost and maintenance.

sal

[ManixFan]

We've played around with a variety of serration shapes, sizes and angles. As Chapman stated, sharpening the serrations on both sides with a shapmaker reduces the "walk". On our kitchen knives, tlting the blade to the right wil also reduce the cutting curve in large objects.

We believe that what we're doing is the best balance for performance, cost and maintenance.

sal

I am certainly enjoying the extremely sharp serrations on my SE G-10 Police 3. This is my first SE Spyderco and I really think they got it right.

I can just see bagels quivering in fear whenever I approach them with my Police and it slices through baguettes and steak with finesse. Now I can cut a steak sandwich on a baguette into party sized appetizer's with ease :D

[zhyla]

A friend of a friend has a business he started that uses custom machinery with CNC stuff to sharpen saw blades. Like you stick an old hand saw in it, it looks at it, and then sharpens it.

Point is I think with enough R&D you could do symmetric serrations cost effectively. Though personally I think the asymmetric serrations work just fine.