I take it that Lorien asking questions of me is an invitation back into this thread and a willingness to accept a waver on my word about not posting here again on this issue, If it is not, please advise, and I shall delete this post in its entirety.
Lorien,
It is you that is not thinking of this right, as is the case with most who speak about this subject. By "sqishing" a design and pushing material away or INWARDS of the parent metal's surface, that then makes the plane of the parent metal a lot more than just a neutral plane. It is the reference plane by which all following calculations must be based on, and not the other way around. What you're doing is basing all your claims on the newly created "web" of the I Beam created by the fuller. When you apply the correct procedure for analyzing the fuller by using the plane of the parent metal, then it is obvious that the sectional area of the fuller neither stiffens nor strengthens the knife.
This is all I am saying, yet so many here seem to think otherwise.
That is not true Lorien, you are doing what I mentioned before and what so many others do. You are using the newly made WEB of the fuller as your reference point to that statement. You are making that claim based on the strength of the fuller, NOT the strength of the original parent metal of the knife. Sure the thinned wall of the fuller is made stronger by the flat horizontal FLANGES on top and below it of the parent metal, BUT it is WEAKER than the strength of the actual parent metal before it was thinned. Stop throwing out the water with the baby hoping that the baby won't be missed. You cannot use the new thinned wall/web of the fuller as the reference in establishing the overall strength of the blade, which can only be done by using the original thickness of the blade BEFORE the fuller was created.
I doubt that those who made knives in the distant past did all the proper calculations or even thought clearly about what they were doing. We cannot out-rule them doing such things solely on the basis of aesthetics, so their blades would be favored over others merely on looks. Just because someone has made something with a flaw in it in the past does not automatically nullify the flaw in the present.
And car axles are NOT struck hard with other heavy pieces of steel along their longitudinal axis. Why are you using them as an example in this matter? They are irrelevant to the subject at hand.
You are perhaps not thinking about this clearly again Lorian. Your statement above is paradoxical, which in itself makes it another false statement if the paradox is quantified.
You say that
"a fuller cut into a knife doesn't make that knife stronger", and then you use a convoluted example as to how it does. The reason it is convoluted is because yet again, you are throwing the baby out with the water and hoping. How can a knife designed with a fuller be stronger than an otherwise identical knife of the same weight (containing the same amount of material) that is thinner by the amount that would have been contained within the fuller? The amount of metal removed from the fuller on a thick blade would NOT decrease the overall thickness of a blade by any more than about 0.3mm to 0.4mm. So you're saying that for instance, a 6mm thick blade having a fuller whose web/wall is 3mm thick, would be STRONGER than a 5.7mm thick blade without a fuller. What nonsense Lorien. The wall/web of the blade with the fuller is almost HALF that of the blade without the fuller. How can a 3mm wall be as strong as a 5.7mm wall? Doing more work with less material? But you are not doing the SAME work, we cannot rewrite the laws of Physics, you cannot take away something and be left with the same thing. If we could, then we could also create something from nothing. None of that will ever happen in the real world.
You having tested as many knives as you have does not add sound scientific credence to any visual observations therefrom because the moment at which the fractures occur, and the speed at which they occur cannot be monitored by any human eye as they are occurring. All you are doing is making an assumption; it is not even an observation during the fact, but only one AFTER the fact. Which leaves it open to error.
But the truth can always be found in the seemingly irrelevant. I am glad you said what you did in that last statement Lorien, therein lays the truth of the matter if you have a truly analytical mind, but you haven't picked it up. Please try following me on this
First, an I-beam or H-beam, which is what a fuller is, be it with parallel or opposing concave walls, is a beam with an I or H-shaped cross-section. The horizontal elements of the "I" are known as flanges, while the vertical element is termed the "web". The web resists shear forces, while the flanges resist most of the bending moment experienced by the beam. Beam theory shows that the I-shaped sections is a very efficient form for carrying both bending and shear loads in the plane of the web. On the other hand, the cross-section has a reduced capacity in the transverse direction, and is also inefficient in carrying torsion, for which hollow or solid structural sections are often preferred.
A knife being struck hard on its back by another heavy metallic object experiences MORE torsion and transverse forces on its blade when it is hit than it ever does or can experience bending or shear loads, because when it is struck by another solid steel implement, it is NEVER struck EXACTLY perpendicular to its vertical OR horizontal axis. The direction of force applied is always offset from those axes, the other bar or knife always comes in at an offset angle to the horizontal or vertical of the knife. It would be almost IMPOSSIBLE for it to be struck PERFECTLY square. That means that the main forces causing the problem will be torsion on the blade, IOW, the blade CONTORTS and twists on its latitudinal axis along, in and around the fullers longitudinal axis.
What that means is that when it is struck at let's say a 45 deg angle on its spine, that the fuller actually allows the metal to twist and vibrate, or CONTORT, between the top and bottom plane of the fuller, MUCH MORE than if the fuller was NOT there. It is this vibration that induces acoustic resonance into the blade which seeks out any weakness in it so they can dissipate quicker, ie with less effort; those forces too like to abide by the law that anything takes the path of least resistance. Therefore any imperfections in the blade nearest the fuller, ie the spine, are quickly sort after by the propagating powerful acoustic being produced. This means they will quickly find these microscopical flaws and turn them into fully blown FRACTURES of the spine which then make the whole spine crumble once it reaches its critical level. As can be seen on hard use tests where the spine of a fuller blade is hammered through wood and the knife just breaks in half, yet when the VERY same blade is made without the fuller, the knife does NOT crumble. Check the user called vinihull on Youtube. He did the same test with the same knife, one with the fuller and one without, have a look and see what happened, then talk to me about fullers. It is the vibrations induced into the blade by this thinning metal of the FULLER that does that, it is easier to induce vibrations into thinner metal than thicker. Either way, it is these acoustic vibrations which are the catalyst for the catastrophic events which may follow.
The reason I beams are made for the construction industry is to reduce the weight of the beam significantly, instead of having to use SOLID beams which would make high raised building impossible to stand up with the weight of all the steel near the top of the structure, and also for financial reason, solid steel beams would be extremely costly when compare to the reduced I beam. Not only that Lorien, but what's been overlooked here is that in a building there are MANY other I beams interconnecting with other given I beams in all directions to it that minimize the torsion of twisting effect on any given beam. The torsion is reduced so that the structure does NOT crumble and break due to one beam wanting to twist on it axis excessively. The other beams running off it stop it from doing that... do you get what I'm saying? IOW, buildings are not made from ONE solitary I beam. So that statement you made is also null and void in this matter.
BUT THAT does NOT apply to a standalone beam or fuller. There is nothing BRACING it from twisting itself into annihilation through the acoustics produced by it when it does.
Jesse Busse made a thread about the acoustic resonance that can be damaging to a blade. He made a nice mod to the handle of the TG14 whereby he hollowed out opposing sections of it making it into a form of I-beam. The hollow sections take away the metal which is touching the palm of the hand, thereby eradicating the vibration on the palm of the hand, and re directing it to the spine via the webbed inner walls of the blade's handle.
http://i80.photobucket.com/albums/j176/jerrybusse/LightBrigadeHandlecutaway.jpg
But here's the thing about hollowing out a handle instead of the blade fore of the ricasso. If the handle is struck so hard as to cause it to fracture via acoustics, then your hand will have been fractured as well in the process. This means that whether the knife itself remains usable or not in such circumstance, your hand wont be. So hollowing out the handle area is nowhere near the jeopardy of hollowing out the cutting blade area. Personally, for other reasons, I prefer to leave all the steel in the tang, but others prefer it removed.
I hope that is enough for you to see where I am coming from on this matter Lorien.
We cannot defy the laws of physics, we cannot remove something and remain with the same thing, or better, which many here are erroneously alluding to, and... Acoustics can become a serious problem with fullers. The truth about it all has been in front of you all the time, you stated it yourself, but it takes a little discernment to figure it out.
