New Fusion?

[babakanoosh45]

I just received a new SOG Fusion Jungle Primitive. Seems like a functional Utility/Camp knife. It seems to be a bit on the Thin side compared to other knives I have in this catagory such as my Ontario Spec Plus. Has anyone else picked up one of these and what are your thoughts? P/S The saw teeth on the back are amazing in that they saw like Crazy!!!! Thanks... ~baba~

 

[Vaako]

Thinner isn't necessarily bad.

There's been a huge over-emphasis on thick blades, I think. Knives are usually used to cut, not as pry bars. A thinner blade normally means a thinner edge and a lower edge angle. That all adds up to a knife that cuts better than one with a thick blade.

Tens of thousands of people in Latin America use machetes as "jungle knives" regularly for most of their adult lives. Those machetes are made of so-so carbon steel about a 1/16" thick, tops. For normal cutting and chopping, they don't break that often, either.

I hope it doesn't sound like I'm getting on your case, there just seems to be an immediate negative reaction to thinner blades these days.

 

[Rat Finkenstein]

One cannot make accurate sweeping generalizations about blade thickness and cutting ability. It all depends on the blade geometry. Machetes and the like usually do not even have a primary grind.

I have little interest in the Jungle Primative, because they use a bottom end steel and I don't like sawback knives.

 

[babakanoosh45]

Hey, Thanks for the replies. I don't feel as though your getting on my case, I appreciate your knowledge. Please understand I was not making a negative statement regarding the thinner blade on the Fusion. I Was stating that it is thinner than all (MY) knives in the same general size and catagory. I also made mention that the Saw portion of the blade cut very well. (A Positive). Basically I was looking for other Fusion Owners Feedback. I am still greatful for the time & info you have supplied regarding this post...

 

[SIRGALANT]

my local knife shop carries these for $100 aussie dollars , a complete rip off in my opinion for such a gimmicky piece of exscretement that spencer frazer pulled out of his ass .

 

[babakanoosh45]

For $40.00 USD. And $5.00 Shipping and one of these shows up at the house from eBay. I have been using in the woods to setup some ground blinds out of old Blow downs and it has been doing very well. It chops/saws/and prys with gusto. It being so light, I have to put a bit more swing in it on larger branches, but it makes good clean cuts. For $40. I am satisfied for now. ~baba~

 

[SIRGALANT]

good for you mate :thumbup: glad you like it i`m just saying i won`t be buying one

 

[Vaako]

One cannot make accurate sweeping generalizations about blade thickness and cutting ability. It all depends on the blade geometry.

Better go tell Bladeforums moderator Joe Talmadge he's got it all wrong, then.

...because I was paraphrasing his widely cited blade geometry FAQ on the subject.

Edge Thickness

The thickness of the edge is another tradeoff in strength vs. cutting ability. The thinner the edge, generally the better it will cut, but a thin edge is weak and can chip out or roll over faster than a thick edge. A thick edge is strong, but doesn't cut as well.​

...which is why I said, "a thinner blade normally means a thinner edge and a lower edge angle. That all adds up to a knife that cuts better than one with a thick blade."

So, yeah, one can make accurate "sweeping generalizations" about blade thickness and cutting ability.

 

[Rat Finkenstein]

That quote is not about the stock thickness.

Edge thickness is different than stock thickness. That is why I mentioned the blade geometry. Many knives made from thinner stock have little or no primary grind (like machetes), so they might easily be out cut by a knife with a decent primary grind that is 1/4" or thicker at the spine.

Knives with thinner stock do not automatically have better geometry than thicker ones.

 

[Vaako]

That quote is not about the stock thickness.

You're right it's about edge thickness.

...which is why I said, "a thinner blade (i.e. thinner stock) normally means a thinner edge and a lower edge angle. That all adds up to a knife that cuts better than one with a thick blade."

Many knives made from thinner stock have little or no primary grind (like machetes), so they might easily be out cut by a knife with a decent primary grind that is 1/4" or thicker at the spine.

"Many knives"??? Weren't you warning about sweeping generalizations? Many extremely thin bladed knives are also incredibly well made with fine cutting edges (take a look at a sashimi knife some time.)

Terms like "out cut" are vague, too.

But even if your statement was true and I'm certainly not conceding it is, thin blades don't need as much of a primary grind to cut well (i.e. deeply) precisely because the stock thickness is reduced. A thin blade doesn't have to displace as much material in order to pass through the cutting medium.

Here's an example:

Stock thickness? Really, really, really thin.

Primary grind? A milimeter's worth.

Cutting ability? They don't call them "razor blades" for nothing.

Knives with thinner stock do not automatically have better geometry than thicker ones.

A thinner blade has to displace dramatically less material in terms of its cross section (i.e. thickness) in order for it to separate the medium being cut. That's why filet knives are ground from thin stock.

That's also why a wire cheese slicer works with absolutely no edge whatsoever. The "cutting edge" is simply the thickness of the wire itself. It's thin, yet it separates the material with little force. Try cutting that same block of cheese with the unsharpened back edge of a Cold Steel Trailmaster, all 5/16" thick worth. See the difference?

Here's an extreme example. A splitting maul and a knife could be made with the exact same steel, temper, flat grind, grind smoothness, but which is going to cut (not chop) its own width more easily into a given material?

I contend the knife will because being thinner it has less material behind the cutting edge to push through the material. So blade thinness definitely does improve cutting ability, all other things being equal.

 

[Rat Finkenstein]

So your intention is to prove you are right by picking and choosing silly examples?

-A splitting maul is not a knife, hardly even a cutting tool, it is a wedge on a stick. I have never seen anyone cut something with a Maul.

-the cheese example is dumb. Go and whittle a stick with your cheese wire (which is NOT even a knife)

-Razor Blades, fillet knives, specialty kitchen knives? why are the only examples you can find that you feel support your argument so specialized they are practically useless outside a narrow scope of work? Why not compare a snowplow and a microtome next?

All other things being equal, two knives with the same thickness behind the edge and angles on the bevel will cut the same, except with certain types of materials. . . But how much cheese and cardboard do you have to cut when out in the woods?

 

[Vaako]

So your intention is to prove you are right by picking and choosing silly examples?

The examples disprove your position. They're not silly. They're good examples which make you look silly.

-A splitting maul is not a knife, hardly even a cutting tool, it is a wedge on a stick. I have never seen anyone cut something with a Maul.

That's the very sort of ultra thick "blade geometry" you advocate. Of course, nobody is going to create a knife with the cross section of a maul. It's an example of your position taken to its logical and ultimately wrong conclusion. A maul has thick blade, fully flat ground from spine to edge, but a cutting implement with that incredibly thick edge geometry wouldn't cut very well.

Compare that to a filet knife. Thin blade, lower edge angles, cuts better.

-the cheese example is dumb. Go and whittle a stick with your cheese wire (which is NOT even a knife)

Just because an example disproves your argument, doesn't make it dumb. The wire doesn't have an edge, but it's still able to separate material due to its extreme thinness. It's able to do so even though it doesn't have an edge at all.

-Razor Blades, fillet knives, specialty kitchen knives? why are the only examples you can find that you feel support your argument so specialized they are practically useless outside a narrow scope of work?

Why don't you refute them on the basis of that "blade geometry" you were citing? "It all depends on the blade geometry," you said.

Show why the examples I provided don't work as well as they do because of their blade geometry (and the thinness of the blade). Better still, show how a thick-blade knife would perform better in their particular scopes of work because of its own "blade geometry".

Put up or shut up.

That's the difference between us, Rat. I'm able to provide real working examples with blade geometry that supports my position. Regular people use those kinds of knives every day as part of their jobs. They're not living some fantasy around their favorite sharpened pry bar that occasionally whittles a stick.

Why not compare a snowplow and a microtome next?

Because I'm not a guy like you. Even your one weak attempt at producing a sarcastic example accidentally supports my position. A snow plow has a thick blade with a thick edge and doesn't cut very well. A microtome has an incredibly thin blade and a very low edge angle. Why don't you run your hand across each edge surface and get back to me which cuts better?

All other things being equal, two knives with the same thickness behind the edge and angles on the bevel will cut the same,

Make the knives even more identical and you can be sure they'll cut the same.

But the real world doesn't work that way. Knives come in different blade thicknesses and that definitely does make a difference on how they cut.

Let's say two knives both have the same flat chisel edge of 25 degrees (to reduce all other edge variables). People certainly are making chisel edged knives these days, Rat.

Now let's say one knife has a blade thickness of over a 1/4 of an inch and the other has a thickness of 1/8 of an inch. They're not going to cut the same. That's just the point you're missing. They don't have the same amount of thickness behind the edge even though they have the exact same grind at the exact same angle.

The snowplow isn't going to cut like a microtome.

 

[Rat Finkenstein]

Writing a long post saying nothing does not prove any point (if you have one)

your failure to grasp the concept of blade geometry, or to comprehend written text is not my problem.

Only a fool would come to the conclusion that I advocated cutting with a thick wedge like a splitting maul, or that it defines the term "blade geometry".

A fool. . . or someone being deliberately obtuse. (Not that there is much difference)

 

[Vaako]

Writing a long post saying nothing does not prove any point (if you have one)

Translation: You can't successfully refute (or perhaps even grasp) any point in that "long post" so you're turning tail and running.

My point is simple. It's been the same one ever since you started posturing with vague comments like "It all depends on the blade geometry."

A thinner blade normally means a thinner edge and a lower edge angle. That all adds up to a knife that cuts better than one with a thick blade.
​

There. Is that short enough for you, Ratty?

your failure to grasp the concept of blade geometry, or to comprehend written text is not my problem.

Translation: When asked to put up or shut up when it comes to solid examples of real knives with real blade geometry, you're unable to the former and you don't have the courtesy to do the latter.

Ratty can't deliver the goods.

Only a fool would come to the conclusion that I advocated cutting with a thick wedge like a splitting maul, or that it defines the term "blade geometry".

Translation: Name-calling and a false attribution of position. That's sloppy and dishonest debating. I never said you advocated cutting with a thick wedge like a maul.

What I said was,

Here's an extreme example. (See ratty? That means it's an example provided for clarity, not to be taken literally) A splitting maul and a knife could be made with the exact same steel, temper, flat grind, grind smoothness (We're talking "blade geometry" ratty. Two cutting wedge shapes. A really thick one and a really thin one), but which is going to cut (not chop) its own width more easily into a given material?

I contend the knife will because being thinner, it has less material behind the cutting edge to push through the material. So blade thinness definitely does improve cutting ability, all other things being equal.​

A fool. . . or someone being deliberately obtuse. (Not that there is much difference)

Translation: More name calling. You're the one being deliberately obtuse and you're becoming increasingly obnoxious with each subsequent reply.

If you're having trouble understanding why a thin edge cuts so well, ask one of the grown-ups on the forum for help.

 

[BubbaGanew]

" Blade Thickness

Blade thickness or thinness is important to both strength and cutting ability of the knife. A thick blade will generally be stronger. But a thin blade will generally have a thinner edge -- and thin edges cut easier and better. So the choice of blade thickness is driven by the compromise of strength vs. cutting ability, just like the choice of point type.

Once the blade thickness is chosen, the particular grind type (see below) can reinforce the attributes of that thickness, or try to make up for any weakness. For example, on a thick blade, a flat or hollow grind can be utilized, so that even though the spine is thick & strong, the edge is thin and cuts a bit better than expected. Or on a thin blade, a sabre grind can be used to make the edge a bit stronger than it would otherwise be. Of course, the grind can reinforce rather than counteract the blade thickness.

- Edge Thickness

The thickness of the edge is another tradeoff in strength vs. cutting ability. The thinner the edge, generally the better it will cut, but a thin edge is weak and can chip out or roll over faster than a thick edge. A thick edge is strong, but doesn't cut as well.

The blade shape, plus the thickness of the blade spine, combined with the grind type, determines the edge thickness.
The edge thickness is one of the only factors that can be modified easy by the knife owner (rather than the maker). Remember that if you're not happy with the way a knife is performing, there's no reason you're stuck with the factory edge. Feel free to re-sharpen, grinding a lower-angle thinner edge into the knife. At some point, if you go too thin the edge will start chipping out, that's an indication that you need to thicken the edge back up. Also see the Sharpening FAQ."

Joe Talmadge