Thickness?

[Shotgun]

So I understand that Busse's are designed to be bomb proof so I'm asking this out of ignorance. If Infi really is as tough as hell, why aren't the knives thinner then their market counterparts to showcase better cutting ability while still retaining the same strength as there competitors? A knife that is lighter and slices better while still having the equivelant strength.

 

[Bigfattyt]

They have released some thinner versions for sure. The Basics, for example. The basic 9 is 1/2 inch if I remember correctly.

The BAD, the SS, the BWM, the Skinny Ash also. and many I am sure I forgot.

If you want to see how well thinner Infi does, look at knifetests.com

He does destruction on the Basic (which is 1/4 if I am correct.....not overly thick for a 9 inch chopper).

Both the Basic, and the Skinny survive more stupid abuse than Any thickness of knife should.



Thinner offerings are something we are pushing for all the time.


One thing, is that Busse owners tend to do more abusive thing with their knives than we ought. I have pried and battoned with my SS which is .17 or so at the at the thickest point.

 

[Greg45]

I can see what you're saying, but I've broken too many non-Busse knives to want Busse knives to have the same strength as their competitors.

 

[palegreenhorse]

What competitors? ....Theres plenty thinner INFI .14, 15 etc. plus the Boney AD, Shiva, and Culti are found in .125 It ain't gotta be thick to be tough, this isn't s30v.

 

[d762nato]

I've got a hack and a culiti, and both are very thin. So yes there are some thin bladed Busse's around, and their still tough knives.

 

[GrinderMcgee]

A thick knife stationed at the wood pile like a FFBM splits wood with the grain like a grenade! This is the perfect example of where thickness is most useful.

Busse is not out to destroy the competition but makes models based on consumer preferece and request. They want 'em thick and heavy.

Right now I want the Basic back!!

 

[Last Visible Canary]

If a crowbar is so strong, you should be able to cut it's thickess in half and still have it be as strong right?

If a knife that's 65rc has really good wear resistance you should be able to tripple it's thickness and use it like a prybar right?

The answer to both is no. Steel retains some of it's properties regardless of the geometry, but the geometry also imparts certain qualities depending on the application. Busse's INFI has one major feature that few other steels have, malleability at high hardness, in this case up to 62rc. That means that even when it's hard it will tend to mash, dent, roll, and deform rather then chip and fracture.

Unfortunately, that works against it in thin cross sections. When you have the edge paper thin, the property of infi that makes it great still shines through: it will mash dent and roll before it chips, but it'll do so very quickly without enough metal behind the edge to support it. Once you bring infi below about 18 degree's per side, the edge can start to become floppy when the application includes high shock stresses like chopping, especially on extra hard materials like knotted or frozen wood.This isn't to say that the knives have to be 1/4" to sustain their edges. You could make them 1/8" thick as long as the geometry right behind the edge was thick enough to support the edge.

But why can't you use other manufacturers knives like prybars? Because the property of their steels transfers over to the thicker geometries, just like busse's INFI transfers into thinner geometries. If you take 60rc cpm-s30v that was heat treated for maximum grain refinement it will hold it's edge wonderfully. However, because it has such fine and consistent grain patterns it has less of an ability to transfer shock and isolated stress throughout the surrounding steel matrix. If you pry with that knife, it will have very little flex and it will tend to snap without giving you any notice. This is true if you make the knife 1/8" thick or if you make it 1/2" thick. While you will be able to apply more pressure to the 1/2" thick knife, it will not be as strong as INFI because it can't take as much lateral stress before snapping - as a property of the steel. Infi's smelted and comparably chunky and irregular grain pattern helps it take those lateral stresses better then the ultra fine ceramic like grain pattern of cpm s30v.

 

[PeterPHWS]

Good explanation LVC .... the grain aspect of the difference in the steels is illuminating .... :thumbup: I never stop learning on here ....

 

[Reeper22]

good explanation lvc .... The grain aspect of the difference in the steels is illuminating .... :thumbup: I never stop learning on here ....:d

+1


...

 

[Evolute]

So I understand that Busse's are designed to be bomb proof so I'm asking this out of ignorance. If Infi really is as tough as hell, why aren't the knives thinner then their market counterparts to showcase better cutting ability while still retaining the same strength as there competitors? A knife that is lighter and slices better while still having the equivelant strength.

In short, Busse sells knives from abouut 1/8th inch thickness to about 1/3 inch thickness, to suit different uses and preferences.


Also, on the thicker knives intended for rough use, Busse strives for higher than equivalent strength and toughness to the competitiors.

 

[fbusmc]

interesting info LVC, made me think about a Paul Chen Katana I picked up a while back, it's the Tori XL and I was wondering if you knew anything about the "layering" of this kind of steel, and whether the grain lines make it stronger or are they prone to "crack apart" on intense impact. I would love to see a true Samurai blade design from INFI..

 

[resinguy]

When properly forged, the layers should not crack apart. Whether such a sword is designed for intense impact is an entirely separate question. My very limited understanding of such Japanese style swords would suggest that they are intended for soft targets, such as tatami mats. I don't think they are warranted against damage if one was to chop a tree down, which is no challenge for a Bussekin sword.

 

[Iboschi]

If a crowbar is so strong, you should be able to cut it's thickess in half and still have it be as strong right?

If a knife that's 65rc has really good wear resistance you should be able to tripple it's thickness and use it like a prybar right?

The answer to both is no. Steel retains some of it's properties regardless of the geometry, but the geometry also imparts certain qualities depending on the application. Busse's INFI has one major feature that few other steels have, malleability at high hardness, in this case up to 62rc. That means that even when it's hard it will tend to mash, dent, roll, and deform rather then chip and fracture.

Unfortunately, that works against it in thin cross sections. When you have the edge paper thin, the property of infi that makes it great still shines through: it will mash dent and roll before it chips, but it'll do so very quickly without enough metal behind the edge to support it. Once you bring infi below about 18 degree's per side, the edge can start to become floppy when the application includes high shock stresses like chopping, especially on extra hard materials like knotted or frozen wood.This isn't to say that the knives have to be 1/4" to sustain their edges. You could make them 1/8" thick as long as the geometry right behind the edge was thick enough to support the edge.

But why can't you use other manufacturers knives like prybars? Because the property of their steels transfers over to the thicker geometries, just like busse's INFI transfers into thinner geometries. If you take 60rc cpm-s30v that was heat treated for maximum grain refinement it will hold it's edge wonderfully. However, because it has such fine and consistent grain patterns it has less of an ability to transfer shock and isolated stress throughout the surrounding steel matrix. If you pry with that knife, it will have very little flex and it will tend to snap without giving you any notice. This is true if you make the knife 1/8" thick or if you make it 1/2" thick. While you will be able to apply more pressure to the 1/2" thick knife, it will not be as strong as INFI because it can't take as much lateral stress before snapping - as a property of the steel. Infi's smelted and comparably chunky and irregular grain pattern helps it take those lateral stresses better then the ultra fine ceramic like grain pattern of cpm s30v.

Well stated. Concise and accurate. Thanks!

 

[Last Visible Canary]

interesting info LVC, made me think about a Paul Chen Katana I picked up a while back, it's the Tori XL and I was wondering if you knew anything about the "layering" of this kind of steel, and whether the grain lines make it stronger or are they prone to "crack apart" on intense impact. I would love to see a true Samurai blade design from INFI..
http://i265.photobucket.com/albums/ii218/fbusmc/SANY2143.jpg

despite what my post made it sound like, I know very little about steel o_0

to the best of my understanding:
the layering of steel in the knife shown is a form of forge welding. You are literally creating a fused surface between the steel layers, but you can't avoid the layered affect without remelting the metal completely through. If the forge welding is done correctly there should be no "delamination" anywhere on the blade. Any form of impurity or lack of fusion during the forgeing process can lead to porosity, inclusions, and lack of proper fusion just like in any other welding process.

traditional Tamahagane, assuming that there are no additional alloying elements in the iron sand used to make it, is the simplest form of steel: iron and carbon. The amount of carbon determines it's ability to be hardened and it's toughness. The layering process tends to put the lower carbon steel (tough) on the outside and the higher carbon steel (hard, but not tough) in the center where the edge is.

So... the layering process wasn't actually something that was meant to increase the toughness of the blade to it's maximum level possible as we would think of it today, it was done to increase the toughness to the maximum level given the material used. The older katana's utilized a kind of building structure to shore up the rigid hard steel at it's center. If you made the entire katana out of the same high carbon steel used at it's center, it would be much more prone to snapping when flexed. This is because the softer low carbon steel that's forged to it's sides act like duct tape when thin band of high carbon steel fractures.



That's about the limit of my knowledge about katanas where the steel is concerned .

two good introductions to the topic:
http://en.wikipedia.org/wiki/Tamahagane
http://www.jhbladesmith.com/en/making-steel/aristotle-furnace.html

If I had to bet on which blade could take more shock stress on hard targets, that paul chen or a busse ak47 brought to the same edge geometry, I would bet on the busse. busse's crazy low carbon high nitrogen concoction is pretty unique in the world of steel, few steels come close to it in shock resistance and malleability at 60rc - the higher carbon Tamahagane doesn't hold a candle in those two properties.