Why Scandie Grind?

Scandis are very easy to sharpen so I see that as a benefit for most people.

I prefer a full flat with a convex edge such as I did with my BK16. I am also a fan of more robust convex edges like my Fallkniven F1. I find that convex edges just work best all around for me. Of course thinner blade stock and FFG will also make it a better slicer.
 
Cryptyc said:
Scandis are very easy to sharpen so I see that as a benefit for most people.
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Easier for novices. Harder for adept sharpeners because they can already hold a proper angle without the "training wheels" and there's a much larger surface area to remove metal from than on a conventional grind with a relief bevel.
 
Rey HRH said:
We're not disagreeing. "There is less steel behind the edge" is equal to me saying it's a thinner blade. What makes it a "hollow ground" is the transition to a thicker spine.

But now I have a question for you because I don't know the answer: what makes a hollow grind a poor wood knife? what part of it gets stuck in the wood? I can possibly see the scandi leveraging it's side against the wood and preventing it from being wedged as the edge moves forward,the wood being shaved away pushes out and is unable to "trap" the knife. I can see the hollow ground being able to cut into the wood unintentionally at a steeper angle and thereby getting wedged. The issue is interesting to me as I've never thought about this.
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The edge on the hollow grind gets stuck, there is no steel on the sides to help spread the wood for the edge to continue cutting.


I don't have a science for it

Just anecdotal evidence


Buck 110 in birch








Spyderco Endura with Convex modification

Even at a steeper angle it bites deeper
















Here is another cut at a lower angle with all my strength








Same angle


The convex kept going the hollow grind got stuck

If I'm cutting soft things like tomatoes or meat it's the opposite effect.

Of course this is generalized and unscientific.

But I'm just a caveman bro

I pick up the knife that works best for what I'm doing.

If it's wood carving the hollow grind is dead last.
 
"What makes it a "hollow ground" is the transition to a thicker spine."

No, what makes it a hollow grind is a concave primary bevel.
 
Thomas Linton said:
"What makes it a "hollow ground" is the transition to a thicker spine."

No, what makes it a hollow grind is a concave primary bevel.
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Okay. It must be just an optical illusion to me that the end of that concave away from the edge results in a thicker spine and the thicker spine probably does nothing to the resulting strength of that blade geometry. Thank you for pointing out my error. At least I had a correct understanding that the hollow ground results in a thinner blade profile behind the cutting edge. Unless, of course, I'm also wrong in that one then feel free to correct me in that respect also.
 
DeadboxHero said:
The edge on the hollow grind gets stuck, there is no steel on the sides to help spread the wood for the edge to continue cutting.


I don't have a science for it

Just anecdotal evidence


Buck 110 in birch




The convex kept going the hollow grind got stuck

If I'm cutting soft things like tomatoes or meat it's the opposite effect.

Of course this is generalized and unscientific.

But I'm just a caveman bro

I pick up the knife that works best for what I'm doing.

If it's wood carving the hollow grind is dead last.
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Thanks for the pictures. I think for the soft things, the hollow grind allows space and air in between so there's no dragging suction force between the surface that's being cut and the blade surface.

For the wood (and I know nothing about planes except I bought one thinking I can use it), you think a factor in the hollow grind is it lacks the geometry in the plane that's called the chipper(?) that thing that makes the chip break off sooner than later for a smoother finish instead of digging more into the wood. Thinking about it, the blade of the plane is like a scandi grind and the shape of the plane is the best for slicing thin layers off of wood else it would have evolved into a different shape.
 
Rey HRH said:
Okay. It must be just an optical illusion to me that the end of that concave away from the edge results in a thicker spine and the thicker spine probably does nothing to the resulting strength of that blade geometry. Thank you for pointing out my error. At least I had a correct understanding that the hollow ground results in a thinner blade profile behind the cutting edge. Unless, of course, I'm also wrong in that one then feel free to correct me in that respect also.
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The transition from concave primary grind to "blade stock thickness" at the end of the grind could look a bit like an "optical illusion" I guess. In reality, its just a more rapid change from the thickness behind the edge than either a flat grind (which is a linear change in thickness), or a convex grind (the exact opposite of a concave/hollow grind). Its that quick transition from thin to thick that makes it a less-optimal design when you're trying to slice the entire blade through the media you're cutting. Cardboard is a good example of something that would be really tough to cut for a deeply hollow ground knife (like say... a straight razor). The shoulders of the grind up by the spine will bind. A full flat will slide through much easier.

But yep, the hollow grind is to reduce the thickness behind the edge. This can be beneficial when you're not cutting through anything deep (ie, like a razor, a human hair is small enough that only the very edge and the bit JUST behind it have any effect on how it cuts). But the main thing is that nothing about a hollow grind makes the spine "thicker" than another design. A hollow ground blade in 1/8in stock still has a 1/8in spine, just like a FFG/Saber/Scandi grind. Its just that the grind changes the thickness behind the edge relative to the other designs.

The overall strength question gets a bit messy, and I'm no expert. From what I understand, the total amount of steel in the blade has a pretty direct correlation to the blades strength. So, in some ways a hollow grind can be used with thick stock to kind of "even out" the overall strength, while keeping the cutting edge, and just behind that nice and thin. But that doesn't really help fix the binding issue when cutting through deep media (the cardboard), or the fact that a really thin edge can get wavy with lots of forces on it (like if you're chopping with a hollow grind) if its too thin.
 
Rey, every single bevel starts where the blade is thicker. We remove steel - bevel - to reduce the thickness of the blade from its maximum. We can do that with one - or more - flat bevels, convex bevels, or concave bevels, or some combination thereof. The bevel did not result in a thicker spine. It is a subtraction from the steel that forms that thicker spine.

If you like a hollow grind, that's just great.

Some feel the hollow grind is best when cutting relatively thin materials where the thicker part of the bevel does not bind since the sides of the bevel are, more or less, thin and parallel. That's them.
 
ocnLogan said:
Cardboard is a good example of something that would be really tough to cut for a deeply hollow ground knife (like say... a straight razor). The shoulders of the grind up by the spine will bind. A full flat will slide through much easier.
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Mostly avoided if you cut at a slant relative to the plane of the cardboard. :D My usual carry knife is a cheapo $4 Italian slipjoint that I reground into a near-zero full height hollow grind and it cuts cardboard like the dickens as long as I don't have the blade perpendicular to the board. This doesn't invalidate your point in the slightest, though--it's just a tip. ;)
 
FortyTwoBlades said:
Mostly avoided if you cut at a slant relative to the plane of the cardboard. :D My usual carry knife is a cheapo $4 Italian slipjoint that I reground into a near-zero full height hollow grind and it cuts cardboard like the dickens as long as I don't have the blade perpendicular to the board. This doesn't invalidate your point in the slightest, though--it's just a tip. ;)
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Just making sure I've got this right. So, you're saying just holding it and cutting at an off axis angle (like say, 45 just to throw it out there) should fix it, as the cardboard will deflect more in that direction (most likely vertically) than it will compress (side to side) if cut straight on/perpendicularly? That makes sense, but I can see how that technique might not get as much value when you're cutting say... really thick 2-3 layer thick stuff? Just because it won't as readily deflect that direction?

Thanks for the tip :thumbup:. I'll keep it in mind if I ever have to slice a bunch of cardboard with my straight razor (which I only use as an example as its my only hollow ground blade :p).

Oh, and I do enjoy my Scandi knives for carving. Its my preferred "whittling" grind :).
 
The Buck 110 is thicker behind the edge than an Endura. Neither blade cuts deep enough for the primary grind to matter.
It's not the type of grind that matters, there are many more details affecting performance.
 
mtangent said:
The Buck 110 is thicker behind the edge than an Endura. Neither blade cuts deep enough for the primary grind to matter.
It's not the type of grind that matters, there are many more details affecting performance.
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:confused:

Do you have pictures?
 
DeadboxHero said:
:confused:

Do you have pictures?
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I am going by what I know of both models. I have owned both. But I don't know your knives. Why don't you just state what is the case for your knives?

In your example, none of the cuts went deep enough for the style of primary grind to make a difference. It is the thickness of steel behind the edge that is making a difference.
 
Thomas Linton said:
Rey, every single bevel starts where the blade is thicker. We remove steel - bevel - to reduce the thickness of the blade from its maximum. We can do that with one - or more - flat bevels, convex bevels, or concave bevels, or some combination thereof. The bevel did not result in a thicker spine. It is a subtraction from the steel that forms that thicker spine.
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So you think I believe the thicker spine in a hollow grind comes from adding steel to that part of the blade and not from hollowing out the sides??? :confused:

I ask because why else do you think it important to tell me it's subtraction from the steel that forms that thicker spine.
 
mtangent said:
I am going by what I know of both models. I have owned both. But I don't know your knives. Why don't you just state what is the case for your knives?

In your example, none of the cuts went deep enough for the style of primary grind to make a difference. It is the thickness of steel behind the edge that is making a difference.
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Pics or it didn't happen :D
 
ocnLogan said:
The overall strength question gets a bit messy, and I'm no expert. From what I understand, the total amount of steel in the blade has a pretty direct correlation to the blades strength.
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This part I do know. While comparing two steel forms with everything else the same except for the amount of steel (which would mean one would be thicker than the other), then the one with more steel will be stronger. However, for the same amount of steel, one can make it stronger by taking away material. If you look at load bearing transverse i beams underneath bridges, the new ones have holes cut out while the old ones use just criss-crossed bars resulting in triangles. The triangles are more costly to make so the new ones just have holes cut out.

They find that the beams with holes are are strong if not stronger than if the holes weren't there and the space taken up with steel. One way to stop a rip from progressing further is to cut a hole at the end of the rip and it dissipates the forces away from being focused at a single point.

A razor blade by itself is very sharp but it flexes and can easily be broken. That's why it has to be in a razor to add strength to the geometry and keep it from flexing and breaking.
 
The only thing I learn on the scandi grind threads is this:

Moras are sweet and .......

Thomas Linton will post and Thomas Linton hates the term "scandi grind".
 
If you want your knife to cut as deep as a Scandi grind, rebevel it to the same edge angle. Comparing a Scandi with a 10 degree per side (dps) edge bevel and a flat grind with a 20 dps edge bevel will have the Scandi cutting much better on shallow cuts. Get a flat grind or hollow grind and rebevel it to 10 to 12 dps and it's a whole different matter.

Hollow grinds are not necessarily thinner than any other grind. All a hollow grind means is the primary grind was made with a wheel, either contact or grinding wheel. I've seen hollow grinds that were as thick behind the edge as the spine of some knives I have.

Beams with holes in them are not stronger than beams without them if all else is equal. They are lighter and can have a higher strength to weight ratio.

Scandis take longer to sharpen than conventionally ground knives, unless the person sharpening can't sharpen a conventionally ground knife.
 
I am informed that I am said to "hate" "Scandi Grind."

I reserve hate for those who set off IEDs and the like.

I believe "scandi grind" adds little to communication given that different people (and companies) routinely use it to mean different things. We had a whole thread of beautiful knives labeled "scandi," and a good many had secondary bevels. Then we have, "Blade is forged using similar techniques used to forge Japanese Katana samurai swords. Full flat Scandi grind." Or the "convex scandi."
 
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