Cbt = wtf?

elkins45

elkins45

Joined
Jun 17, 2006
Messages
4,090
I was looking at the HG 55 on the Busse website. So what's up with the 'Corrugated Bevel Technology'?

I know nothing about Busse knives, but are they so sharp that you need to add extra friction to the blade to slow them down?:p

Seriously, is there some practical reason for that, or is it just for aesthetics?
 
They're supposed to add lateral stiffness and improve cutting efficiency. My FBM lazers right through cane and other thick, green, pulpy river-bottom growth. I suppose it's the CBT's that help it out. It's pretty sharp though, so I don't know for sure. I think theyre bitchin'.:thumbup:
 
they're supposed to reduce friction, though i'm not sure i understand the ones on the HG55 or, like you said, how they don't increase friction. the ones on the other knives make way more sense for that since they run parallel to the edge.
 
I suppose it depends which way you're cutting. If you use the HG55 for slicing rather than push cutting or chopping, then I imagine that the ridges decrease contact surface area/average pressure, and therefore decrease friction. Provided you're slicing something with enough give not to get caught up on the ridges. (Flesh!)

I would love to test my theory, so if anyone wants to send me their HG55, I'll gladly try it our and report back!
 
On the HG55,I thought the CBT was
to stop the cheese slices from sticking to the blade. :D
 
The HG 55 Military over run is design for all purpose military use.

So regardless of "rank"....if you are a conscript the CBT technology enables you to do crinkle french fries when put on "jankers" thus pleasing the officers and affording promotional oppertunity to NCO status where you can use the knife on cheese slices and potted meat....and even the officers have a use for the technology with nice shaped "butter rolls" to go on their "scones and jam" at tea time...:D:D:D

Or at least it would work like that over here...:p:eek: about 65 years ago.....

In more modern times I doubt there are any specific advantages over a normal grind.....
 
Last edited:
They seem like a legitimate lightening technique. Less heavy than a fatty, but more strong than a skinny.

The best...or better of both worlds, but uglier;):D;)
 
Strabs said:
They seem like a legitimate lightening technique. Less heavy than a fatty, but more strong than a skinny.

The best...or better of both worlds, but uglier;):D;)
Click to expand...

I thought the same, used to lighten the blade without compromising it's strength as much.

But mostly theyre just there because they look cool.
 
elkins45 said:
I was looking at the HG 55 on the Busse website. So what's up with the 'Corrugated Bevel Technology'?

I know nothing about Busse knives, but are they so sharp that you need to add extra friction to the blade to slow them down?:p

Seriously, is there some practical reason for that, or is it just for aesthetics?
Click to expand...

if they run horizontally, they can help to lighten the blade slightly while giving a bit more stiffness, and they reduce the amount space the material is pressing on when sliding across the flats of the blade, which could (theoretically) help reduce binding. I'm not sure if anyone would actually be able to feel a noticable boost in performance from it, but whatever you like is good for you.

when they run vertical like this, to me, they'll increase the amount of lateral flex the blade will have before taking a set at any given thickness. don't know how much benefit that would give either, but it looks interesting :)
 
I've yet to wedge my CBT FBM yet. My old FFBM AND FBMLE got stuck a lot. The latter two are much thicker than the CBT's.
Probably just for looks but I tell myself they are functional ;)
Not sure if I could trick my mind into that with the HG55.
 
Last edited:
Last Visible Canary said:
if they run horizontally, they can help to lighten the blade slightly while giving a bit more stiffness, and they reduce the amount space the material is pressing on when sliding across the flats of the blade, which could (theoretically) help reduce binding. I'm not sure if anyone would actually be able to feel a noticable boost in performance from it, but whatever you like is good for you.

when they run vertical like this, to me, they'll increase the amount of lateral flex the blade will have before taking a set at any given thickness. don't know how much benefit that would give either, but it looks interesting :)
Click to expand...

I'm not sure how removing material could make a knife stiffer. It might be stiffer than a flat blade of equal weight, but the original blade would have been stiffer before you removed material to make the grooves.

It's like saying that fluting a rifle barrel makes it stiffer: it's stiffer than a skinny barrel of the same weight, but a non-fluted barrel of the same diameter is still stiffer.
 
You just answered your own question right there "Its stiffer than a skinny barrel of the same weight"

When Jerry introduced the CBT technology he used the cardboard analogy. Corrugated cardboard is stiffer than flat cardboard of the same weight. With CBT's you get a stronger lighter blade than its non CBT cousin.

A side effect of the CBT's is a smaller contact area so the blade will not get stuck in the material as easily. When I baton hard wood this effect is dramatic, my non CBT chopper gets stuck very easily, my Fusion Battle Mistress hasn't been stuck yet.
 
To me the CBTs are an evolution of the traditional fuller.

The principle of corrugations increasing structural strength in structures is fairly old and if you look at a knife not as a knife but a structure then it may be easier to see the benefits of the CBTs.

The additional coolness factor for me is a big draw. Now if I could get a War Boar with CBTs...........
 
This may help, these images show only the horizontal corrugations, but the vertical ones
would work the same way, only for a slicing motion as opposed to a choping motion.

1.jpg


2.jpg
 
elkins45 said:
I'm not sure how removing material could make a knife stiffer. It might be stiffer than a flat blade of equal weight, but the original blade would have been stiffer before you removed material to make the grooves.

It's like saying that fluting a rifle barrel makes it stiffer: it's stiffer than a skinny barrel of the same weight, but a non-fluted barrel of the same diameter is still stiffer.
Click to expand...

stiffer - not stronger. I'm not sure that the spiral rifling of a barrell is a good example. with a striaght 2 flute drill vs. a spiral flute mill the straight drill is used for long drilling applications because of it's ability to avoid being pulled in any given direction, moving off course. it's not stronger, it may not remove metal as quickly, but it is stiffer.

these are completely arbitrary numbers:
take a standard satin jack at 3/16", and then make another one with cbt. The ball end mill takes a cut of 1/32" at the top, and less deep as it goes towards the edge. at spine side cut, the thickness at the center of the fluting is 1/8" thick. the overall weight goes from 12oz to 10 oz.

the stock satin jack takes 400lbs of force to get it to start bending, and takes a set at 900lbs. The corrugated satin jack takes 500lbs of force to bend, and 850lbs of force to take a set.

Its not stronger, it's actually weaker at the extreme end - but it's "stiffer". it takes more force to make it bend, but not more to make it fail.


the vertical cbt's would have the opposite effect, they would increase the blades ability to flex. They will decrease the strength of the blade slightly at the extreme end (breakage), but not significantly, the main difference the user will notice (if at anything) is a reduction in stiffness.
 
Both examples are good.

CBTs or flutes (not the rifling) on a barrel work the same.
And yes, it makes them stiffer, not stronger.

Reason is, they change the directions of the force vectors going through the material. So, say lateral force is applied, on a standard blade, the force vectors are all aligned. With the CBTs, particularly those on the CGFBM, will change the directions of the force vectors as they cross the CBT, basically enabling the metal to take the force in many directions instead of all in a single direction.

Lateral force on the HG55 will, of course, not distribute, but like the previous posters said, will enable the knife to bend further, because it will bend where the metal is thinnest. Increasing the angle you are able to achieve before the blade breaks. Of course, it will take less force to bend it that far than with a solid blade or wil the CBTs running parallel to the edge.

Also, as stated above, when going through stiff materials, less blade surface will be in contact, thus reducing drag. However, cutting soft material, the material will fill in the corrugations when cutting (especially on the HG55), and increase the drag.

But they look cool, so let's just drink the physics away and look at our purty knives.
 
You must log in or register to reply here.
Back
Top