Bowie balance point

[pageophile]

Hello one and all

Got a quick question about large blades, specifically bowies. Where should the balance point be located? At the hilt, a inch in front, an inch back?

Is this more a choice of personal preference or is there an some "rule of thumb"?

Btw, this is not really a historical question but one targeted at using a big blade in a modern setting.

Thanks for your time and trouble Gents


Best regards,

Page

BTW, Tried the search function this morning and it's acting kinda "hinky", just locks up my computer

 

[trentu]

I often try and balance large blades just at the guard. If it is for chopping I try to balance about 2" above the guard. Gives more energy to the blade.

 

[Stacy E. Apelt - Bladesmith]

trentu has it.
A fighter should be balanced at the guard, to make it light and fast. A camp knife (chopper) should be balanced just behind the guard to increase the inertia.

 

[TekSec]

trentu / Stacy,

trentu says 2" above the guard...is that 2" up on the blade?

Disregard...duh...must be late. I understand what you're saying now...

 

[Kevin R. Cashen]

Ask this question and you will get a dozen different answers from a dozen different users, and all of them correct. I didn’t get a great appreciation for balance points until I started making swords and then it became quite involved. In comparison, knives can fall into one heck of a range and still be cool. I always did, and still do, find all the hype about the balance of a 4” hunter to be quite overdone. When your blade gets out there long enough to have issues with the mass being tiring to wield or slow to reverse direction quickly then balance actually starts to mean something. Perhaps it is use in combat that puts the greatest emphasis on balance that makes me downplay it in knives; I don’t like to envision my knives being used in that manner.

But I believe that what I have learned in swords applies to knives. You have three considerations- 1. point control (including quick recovery and tracking in thrusts), 2. cutting chopping mass, 3. overall fatigue of using the blade.

If you wish to make a pure chopper, you only worry about 2 and 3. If you wish to make a pure stabber, rather uncommon and unpleasant for obvious reasons, then you worry about 1 and 3. Although back in the day when they actually made fighting blades things got very complex with blades like rapiers, which I am still working to understand better due to the tip weights caused by a fighting style that no longer exists. I often will get deep into what percent of cut versus thrust my customers sword technique involves before grinding the blade and bringing the center gravity into position on the blade while keeping overall weight in the range desired.

Most knife customers will want a general using blade which will incorporate all three above considerations, gearing them to what use flips their switches the most will make them happy. If they just want to kill a 2x4 in less than 7 seconds put the balance point well in front of the front finger, I like to think of it as relative to the users hand instead of a fixed point on the blade and many of my blades end up with the balance point on the riccasso just in front of the guard.

One interesting note, I don’t believe I have ever intentionally balanced a knife. If all the visual proportions are there and the tapers in place, it just sort of happens on its own. It is the ultimate testament to “form follows function” that when you grasp the concept of visual balance you can walk through a knife show and tell the blades that will feel awkward without having to pick them up.

 

[pageophile]

Thank you all for the replies, it has been very helpful hearing your input.

Best regards,

Page

 

[the possum]

If your knife is only gonna be used in a static manner, such as whittling, slicing, etc., then maybe the static balance point is what you should focus on, and keep it close to the hand.

If your blade will be quite large, and your planned use will be more dynamic, such as chopping, quick maneuvering, and stuff like that, then we don't need to talk about the balance point. We need to talk about the pivot points. (aka, dynamic balance point, or rotational centers)

One interesting note, I don’t believe I have ever intentionally balanced a knife.

I get where you're coming from here, and I've also said many times that the center of mass will end up wherever it needs to be as a side result of my real goals.

If they just want to kill a 2x4 in less than 7 seconds put the balance point well in front of the front finger, I like to think of it as relative to the users hand instead of a fixed point on the blade and many of my blades end up with the balance point on the riccasso just in front of the guard.

Kevin, if ya don't mind my saying so, I'm a little surprised at the way you've put this. I don't get the impression that you're afraid of working with numbers or technical physical data. I do get the impression you dislike myths. One of those is that the balance point is what controls dynamic handling properties, point control, or chopping power on its own, so perhaps it would be better to talk about the things that do matter.

I believe the search function is working again...

 

[Kevin R. Cashen]

...Kevin, if ya don't mind my saying so, I'm a little surprised at the way you've put this. I don't get the impression that you're afraid of working with numbers or technical physical data. I do get the impression you dislike myths. One of those is that the balance point is what controls dynamic handling properties, point control, or chopping power on its own, so perhaps it would be better to talk about the things that do matter. ...

I am not sure I follow your meaning. Oh the heck with it, I know I don't follow your meaning. What are you saying here Possum?

One part of the confusion may be my stubborn habit of not going with the catch phrases and jargon of the day*, so I am stuck on old notions and terms like "balance point" and center of percussion (and I still even prefer "sweet spot" to that). Since the Turner article went up at the Arma site I have been seeing the words "pivot points" thrown around like a slogan in a mass advertising blitz. This seems to be cyclical, before this new fascination a few sword guys got together and came up with the new science of "harmonic balance" and everybody was looking for the 2nd, 3rd or even 4th "nodes" on their swords. Next year somebody else will come along with a new string of physical equations and all new terms for the same old points on a stick that every kid learns when his Louisville slugger connects right and puts one out of the park, or connects wrong and leaves his hands stinging.

*I know, I know, there is nothing new about it, Newton, Galileo and old amories etc... Heck the first trog to chip a spearpoint may have had a slide rule for all we know. All the same, old concepts can become all the rage in modern catchphrases as well. Yes, I am aware of this stuff I just prefer not to get mired and bogged down in it.

 

[Stacy E. Apelt - Bladesmith]

I am with Kevin,I am a numbers person,but when it comes to balance - I make a knife to "feel" right in the hand. Sometimes it takes several knives before the final balance has the feel for the purpose the knife is being made. In making the knife it is hard to preplan the balance point exactly. In the old days , swords were balanced by adding weight to the pommel. The amount added depended on the "Feel" of the sword.A properly balanced blade ,(from a 3" skinner to a 30" katana), feels light and moves smoothly in the hand as it is manipulated.Pick up a $30 Pakistani katana, then pick up a Nihonto and you will immediately feel what I am saying. That "feel" is put in the sword by skill, not math.
Stacy

 

[ChainsawMan]

I know that I'm a newbie to this forum, but I say that "balance point" is a bogus factor in knife making. My customer wants a 12" Bowie, and that's what I give him. He's happy with the knife, not the "balance point". I'm currently making one for a Marine being deployed to Iraq soon, so I may be more careful, since it very well might be used for real. Otherwise, no.

 

[Kevin R. Cashen]

... In the old days , swords were balanced by adding weight to the pommel. The amount added depended on the "Feel" of the sword.A properly balanced blade ,(from a 3" skinner to a 30" katana), feels light and moves smoothly in the hand as it is manipulated.Pick up a $30 Pakistani katana, then pick up a Nihonto and you will immediately feel what I am saying. That "feel" is put in the sword by skill, not math.
Stacy

Stacy, I am with you completely, mostly because I am not a numbers man, numbers bore me to tears and have been a stumbling point for me all of my life, but I would like to discuss the one point that I must differ with you on; if for no other reason than to save you from the zealous reaction you are inviting with the point about just adding weight to the pommel.

In studying original ancient swords, the history surrounding them and in my own experience I have found that the pommel really needs to be treated as an after thought to proper proportions and blade function. I believe it is a completely modern notion that one can punch out a sheet of steel, grind bevels on it and make it all right simply by putting a given mass into the pommel, and this has lead to the overwhelming numbers of “sword shaped objects” on the market. I have found that one needs to take a specialized craftsmen approach to sword blades, as if somebody else unknown to you will be hilting it, and design the blade to handle quite well in its own right while letting the other guy worry about the final appearance and function of the hilt and pommel. There are also historical examples that also strongly point to this. There is nothing I detest more than a 5 lb. sword with a cannon ball peened on the end to make it swing like steady cam.

I will let others debate you on whether Weyland used an abacus and slide rule or a hammer to make his swords, as I am more in your corner that sword smithing is a experience and feeling thing more than equations. After all isn’t that what we all strive for, to be as good as those guys who didn’t need to think too much about it, they just did it, and did it very well.

 

[Kevin R. Cashen]

I know that I'm a newbie to this forum, but I say that "balance point" is a bogus factor in knife making. My customer wants a 12" Bowie, and that's what I give him. He's happy with the knife, not the "balance point". I'm currently making one for a Marine being deployed to Iraq soon, so I may be more careful, since it very well might be used for real. Otherwise, no.

That was kind of the message I had in mind with my first post, although I may have done a terrible job at conveying it. In my experience balance points on knife blades are mostly notable when they have gone very wrong, at least that is the only time I pay any real attention to them. For the most part if you have a good sense of proportions, can grasp proper tapering techniques and cross section of intended purpose there is no reason to give it much thought on a knife blade. I have however seen knives by folks who were still struggling with these concepts and the knife almost hurt me just holding it, much as less using it. And then there are those knives that hurt you from just looking at them...

 

[the possum]

I am not sure I follow your meaning. Oh the heck with it, I know I don't follow your meaning. What are you saying here Possum?

I guess I'm saying I'm just surprised at this perspective since you're so willing to delve into science and known physical properties when it comes to the metallurgy and heat treatment of your blades to eke out that last ounce of performance. I didn't figure your approach to balance properties would be so much less technical.

I recall you've made comments to the effect that a person can do a good job with heat treating with the low tech approach, but they still need a good understanding of the underlying principles to pull it off consistently. The same could be said of balance. The blade may "feel good" to the maker, and feel lousy to me. Does he understand why the blade moves the way it does, or how he can change it at will?

Take this statement for example:

That "feel" is put in the sword by skill, not math.

While I completely agree this is true, at the same time I believe it would be very easy to make much more precise observations about handling properties so we can discuss them in a more meaningful way. I'm sure I could pick up ten swords by Stacy or Kevin, and they'd all "feel good". "Yeah, I really like the feel of that falchion's balance. That rapier feels good too. And that type XVIII feels real good."

What the heck could anyone else reading my oberservations here on the net learn about the handling properties of those various swords?

The smith may make the sword by feel, but the math can explain why it feels the way it does. Heck, forget the M word. We don't even need numbers at all. And here's another big thing. That feel can be decieving. The other part of my reply regarding myths was because you said "...If they just want to kill a 2x4 in less than 7 seconds put the balance point well in front of the front finger". It seems to be conventional wisdom in the knife community that if you want chopping power you need to move the center of mass forward. I say it's not so simple.

Example: My HI khukri sure "felt" like a solid chopper. Big thick & heavy, with a balance point way out there. Know what? I was left unimpressed with its chopping power, and its handling qualities, so I used those dang physical principles to modify it. I nearly doubled its chopping power at the tip, while bringing its balance point back almost 3". Huh? Made it a heck of a lot easier to swing too.

Next year somebody else will come along with a new string of physical equations and all new terms for the same old points on a stick that every kid learns when his Louisville slugger connects right and puts one out of the park, or connects wrong and leaves his hands stinging.

These are different things. The "sweet spot" may or may not coincide with the location of the pivot points or whatever you want to call them. And again, does the smith know how to move the sweet spot, or make a blade that will never leave the hands stinging?

Yes, I am aware of this stuff I just prefer not to get mired and bogged down in it.

That's certainly your or anyone else's choice. But at the same time, even an ol possum can get his head wrapped around this stuff; it ain't that complicated. Meanwhile the stuff you talk about on a daily basis regarding steel leaves my head spinning, yet I try to struggle through it so I can understand how to make a better blade.

 

[Kevin R. Cashen]

Thanks Possum, I understand better now. I don't feel that all of the physics many dwell on is hogwash; I just have to pick and choose what things I am going to be neurotic about the minutiae with. Already my productivity is perhaps half of what it should be due to obsessive metallurgical dissection of everything I do, if I decided to spin off into crunching numbers for pivot points and moments of inertia, there would be nothing left of my day for actually making a living, so I have to rely on my instincts for the distributions of mass.

You may have misunderstood me when I said just move the balance point forward if all you want is to chop 2x4’s, what I was saying was for a knife that is just a 2x4” killer and not much use for anything else then simple concepts like just moving the balance point around may work. I had my fun in the cutting competitions, I guess it is up the spectators to determine whether I was any good at it, and a 2x4 chopper that can also cut other things is indeed more complex than just moving balance points, it is in the geometry itself. A 1 ¼” wide blade will have a heck of a time out-chopping a 2 ¼” blade no matter how far forward the balance point. Certain grind angles will also come into play as well as the angle of attack for the edge in relation to the handle. While we are at it I think enormous gains can be had in a whole lot of knives simply by tweaking the handle design without touching the blade. I believe all of the dynamic “points”, “nodes” ,or whatever we wish to call them, are too close on a blade under 12” to play as large a role as all these other factors.

I guess I am saying not to worry I indeed don’t believe it is as simple as moving the balance point around, but Mr. Pageophile simply wanted to know a good spot for it and we certainly gave him some food for thought.