At last I had a BM in my hands

Falcenberg · Apr 11, 2001

At last I was able to meet that friend of mine who bought a BM from Andy.

And obviously I had the BM in my own hands.

I am not going to say "What a knife!", just because it seems obvious, but I have to ask two questions:

1) We weren't able to find any "Busse" logo on the blade or on the handle or on the sheat. Is there a logo, or all BM are "anonymous"?

2) I wasn't able to see the famous convex-flat grind on the blade. It seems a flat grind, one side deeper than the other, but are straight lines, no convex ones.

Can you help me?

Falcenberg

Andrew Lynch · Apr 11, 2001

It's my understanding that the convex grind is only on the secondary grind. If you point the knife away from you, the convex grind should be on the right side of the blade. There is noticeably more of a secondary grind on that side, on my knife atleast (as in, you can see more shining metal on that side).

I've heard that because of military secrecy reasons or something, no Busse logo is put on any of their true user/military knives. They do place them on some of the more collectible ones though (like the Aftershock bolo). But apparently, while no Busse logo exists on the outside, underneath the pressure-applied and fastened handle slabs, there exists some kind of a Busse logo.

By the way, are your primary grinds perfect or a little off? I found mine were a little off, and am wondering about other Busses.

I'm sure you'll be wanting a Busse pretty soon. It's hard to avoid.

Falcenberg · Apr 12, 2001

With secondary grind do you mean the very edge of the blade? I cheched it too, I saw more "shining metal", but it seemed a flat grind, not a convex one. Now I cannot check the knife again, because I and my friend live quite far and now he is abroad to work.

It seems quite hard to see a logo under the pressure-applied and fastened handle slabs, isn't it?

What do you mean with "a little off"? Can you describe it? When I checked the BM, the grinds seemed very straight. Only the edge has a little curvature in the middle, i.e. it seems it was honed a little too much.

And about wanting a Busse for myself, I am looking for the Future Busse Folder. I would buy the BM for me too, but it is very hard to import it in Italy, just because Italian Customs and Mail Service are very slow, very often goods are stolen when they reach Italian Customs and often some LEOs at the Italian Customs "create" new laws stating a knife is an illegal one, so they take your actually legal knife. We used a bunch of tricks to import that BM, and we used an expensive Private Delivering Service, because that friend of mine needed a rock-solid fixed blade for some tasks now.

I think a folder could be easier to import, and I like to carry my knives as much as I can. A folder is easier to carry "legally" than a huge BM.

Furthermore, I am a little curious about having a fixed blade made with an alloy from Crucible, like CPM10V, CPM9V or CPM3V, so I am thinking about having a knife like that. I know the BM is now the best you can have, because those alloys are still a little "experimental" (is this word right?), but I can wait ...for now

Falcenberg

Andrew Lynch · Apr 12, 2001

Thanks for your response,

When I said my grinds were a little off, I meant the primary bevel. Basically one was ground a little farther than the other, and make it look significantly off, when the edge was actually right on center. I give more details on my "Steel Heart 2 E First Impressions" in the Knife Reviews and Testing forum.

Oh, and about those Crucible steels, check out Cliff Stamp's Website here (the materials part):

http://www.physics.mun.ca/~sstamp/knives/materials.html

He states in one of his tests (CPM-10V vs INFI), CPM-10V holds an edge better than INFI, but Cliff states that INFI most probably has better toughness and corrosion resistance. These new crucible steels are very interesting. I can't wait until they are widely used.

Cliff Stamp · Apr 12, 2001

CPM-10V is a carbide replacement, and yes it has a very high wear resistance and strength. However it has a very low toughness and ductility. If I had a BM out of CPM-10V it would quickly be turned into multiple Mean Streets the first time I used it on anything suitable for its size. CPM-3V would be a decent choice for a large knife. I have used a medium sized 3V blade from Ed Schott and was pleased with its toughness and edge retnetion and Ed has some impressive flexibility shots on his website.

-Cliff

Falcenberg · Apr 13, 2001

This post is about some opinions on Busse knives and some other general things. I didn't split it in another post in "General Discussion Forum" or in "Knife Review and Testing" because it could be hard to follow the stream of my thinking. I hope I didn't make a big fault.

Dear Andrew, thanks for your answers too.

Sorry, but being Italian I am not so proficent with English. Can you explain me again what do you mean with "a little off" about the grinds of your blade? Are they not straight? Do they have different angles? Was one side ground more than the other? Does your blade have a little "belly"? I'll read your other post, but I am asking just to be sure to understand.

I still don't understand where I can see the convex grind on the blade of my friend's BM. All the lines of the section of the blade seem straight. As I could see, the very edge has a different angle from one side to the other, but again the lines of the profile are straight, not convex.

Cliff, thanks for your answers and your work in testing new alloys and blades. You actually test knives, I can only see the data sheets you have in your site, so I have only a theorical point of view.

But looking at the data sheets of CPM alloys, I don't understand why a CPM-10V big blade would be so brittle.

My alloy of choice would be CPM-9V for a big blade, but I don't see this alloy in any thread in our Forums. Let discuss 3V, 9V and 10V.

I don't want to make a blade thin like a sheet of paper, that cuts forever and doesn't break. If I remember the knives in 3V you tested, the thickness of the blade was 1/8". This gives to them a great slicing and cutting power. But my idea about an "almost ultimate" blade could be a blade a little longer than BM, a shape a little different (bowie or tanto, just to have a little more of "point"), and a little thinner than BM, but not so much. I haven't seen the Aftershock Bolo yet, but it could be quite similar.

So, if my evaluations about CPM data sheets are good, I don't think it would be easy to break such a blade, even if it is made of CPM-10V. Its section would be enough to give it a sufficient strenght. About chipping, I have to re-read your tests about CPM-10V blades.

Looking at the charts at the end of the first pages, I can make these evaluations:

- D2 alloy has a toughness of 21. A2 has a toughness of 38, CPM-3V of 50, CPM-9V about 40 and CPM-10V of 25. So, it seems CPM-3V is two times stronger than CPM-10V, and a little tougher than D2, that is, if I remember correctly, a good alloy for survival knives.

- let say the D2 alloy has a wear resistence of 3-4. A2 has a resistence of 2-3, CPM-3V of 7 , CPM-9V of 40 and CPM-10V of 75. So, it seems CPM-3V is 10 times "less resistent" than CPM-10V.

Yes, a 10V blade could be a little brittle, but my blade should be quite thick (a little less than BM). And, again, my alloy of choice could be 9V.

Why am I looking for something different from INFI? If I have to stand again all the troubles and expenses to import an unique knife from USA, I want it is the better that money can buy at the moment. For the moment IMHO some other alloys could have features a little better than INFI in some uses. If INFI would be discovered to be the best performer, I will be glad to have it. But I know the perfect steel doesn't exist. Cliff, I know in your tests you saw sometimes INFI is better, sometimes CPM is better. You know, the choice of an alloy depends the use you think for the blade. And I am still looking for and collecting opinions.

What do I want to do with such a blade? Perhaps nothing more than having a blade that IN MY OPINION AND IN SOME USES is the better blade in the world. This gives a great number of possibilities of choice, ranging from 420J2 if you are a diver to CPM-15V if you need a very small blade to use in a dry environment to cut hard material.

My actual uses of the blade I dream are these: I like trekking through mountains, so I need a big knife to cut branches for the fire, to open a path in the bush, to prepare my food and, who knows, to be used as a weapon (Battle Mistress has a shape very different from fighter, but could be very effective as a weapon). It is not so different from the uses you described in another thread, Cliff. Now I am carrying a Kukri, a medium size fixed blade of good quality, a SAK and a knife for cooking. I have to save space and weight in my backpack!

About corrosion, I prefer a blade stronger and harder to a blade easier to maintain. I can stand to the task to maintain a blade properly, but I cannot make it stronger or harder after it was heat-treated. The main effect of my reading of these Forums since I discovered them, was I started to buy no-stainless knives when I need a knife with better mechanical features.

Cliff, these are my opinions. If you can give me some advices, I will appreciate it very much. Why don't I buy a BM? As I said before, there are some features that I would like to see different. And just because I can wait, I can look for future improvements.

Falcenberg

Cliff Stamp · Apr 16, 2001

Falcenberg:

I still don't understand where I can see the convex grind on the blade of my friend's BM.

Turn the blade upside down with the tip pointing away from you. Look down the edge and right after the index finger cutout you should be able to see a cross-section view of the edge and the convex/flat nature should be clearly visible.

D2 alloy has a toughness of 21. A2 has a toughness of 38, CPM-3V of 50, CPM-9V about 40 and CPM-10V of 25. So, it seems CPM-3V is two times stronger than CPM-10V, and a little tougher than D2, that is, if I remember correctly, a good alloy for survival knives.

First off you can't interchange strength and impact toughness, they are very different material properties. The numbers for toughness you quoted are basically charpy values which measure how much force it takes to break a piece of steel with a large hammer. In regards to strength, most cutlery steels are very strong, unless differentially tempered which makes them very weak (and at the same time very tough).

let say the D2 alloy has a wear resistence of 3-4. A2 has a resistence of 2-3, CPM-3V of 7 , CPM-9V of 40 and CPM-10V of 75. So, it seems CPM-3V is 10 times "less resistent" than CPM-10V.

This is one of the cases where it is very easy to get the wrong idea. Edge holding is not directly proportial to wear resistance so while the above numbers are true, they are a little misleading in regards to the performance they give the blades.

Wear resistance is a factor in edge retention of which there are several (strength, toughness, ductility, corrosion resistance) , but in many types of cutting it is not even the dominant one. It is easy to pick a task in which the wear resistance of a steel does not have any great benefit (chopping clear wood) and in fact just makes life harder as the blade will take more work to sharpen when blunt.

For some background information I discussed exactly this issue (10V in a big knife) here :

http://www.bladeforums.com/ubb/Forum4/HTML/002360.html

Yes, a 10V blade could be a little brittle, but my blade should be quite thick

Thickness will give you a decent amount of strength, but will not have the same effect on toughness which is the main concern. And again, because the alloy does not have the base materials properties that you want you are being forces to compensate by altering the design to one of lower performance. A better steel choice would allow a higher performing blade.

My actual uses of the blade I dream are these: I like trekking through mountains, so I need a big knife to cut branches for the fire, to open a path in the bush, to prepare my food and, who knows, to be used as a weapon

The amount of toughness needed here is considerable. Combat could easily generate *very* high impact forces and limbing out trees is one of the hardest things you can ask a knife to do.

Now I should qualify that my opinions on these things are hardly universal. There are lots of people making large blades out of alloys that are significantly more brittle than CPM-10V. Of late CPM-420V (S90V) has been getting a lot of press as a hard use blade steel and it is a lot more brittle than 10V.

You need to be clear as to what your requirements are and what performance baselines you are drawing yout conclusions from. I do not mean to imply that if you take a 10V blade and cut a piece of rope it will fall apart. Nor will it go to pieces if you chop through a clear piece of 2x4.

However if I chopped through a knotty piece of wood at full force I am fairly confident it would not survive, based on a lot of things I have done and conversations with a maker who did exactly that with a 3V blade at a high hardness, at which its impact toughness was greater than 10V at a much lower RC.

Then again, the amount of force you use is also obviously a significant factor. If you took the 10V blade and gently chopped through the knot you could do it without harm. But in the mean time if you had a 3V blade you would have long finished cutting through the wood.

In general, better alloys will allow the blade to be of higher performance, a large part of which is knowing how to optomize the geometry to suit the material - this is not a univeral trait. It is however easy to figure out if a maker does this, just ask them about altering the steel and if they will, but keep the geometry exactly the same then you have a problem (unless they describe how the scope of work and performance will be effected).

One last thing, the bottom line should be the performance stated by the maker as they are the ones grinding the knife. If you can find someone who thinks that 10V will make a good knife for the kind of use you describe *and* will stand behind their work, then you really don't have much to lose.

-Cliff

[This message has been edited by Cliff Stamp (edited 04-16-2001).]

HollywoodDave · Apr 18, 2001

Ummm, is there anyone else out there with small children who isn't exactly ecstatic about the idea of having a BM in your hands?