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Belly vs Back Arching Asymmetry


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Hi Don Noon. I was just waiting for when you will show upp as a Joker playing the best card. Well it is nice that you have put all earlier writing on this site. It becomes much easier for any one starting reading from the beginning.

But let me ask a question based on may unanswered question.

There have been made made statements that there will be no differens in loading with dead weight as Bruce did in the climate chamber and the condition of deflection caused by string load.

I say there is a great differens in structural behavior depending on the fact that the center in the climate chamber force the center down while string. This result in a widening of the center of the belly in the C-bout while the back  become pulled inward.

With the string load condition the end blocks become pulled upward/inward and no movement arises at the sound post. I have described how any one easy can check this. 

Why is it no one try and find out?

Comparing the two differens condition we cannot say there is no differens in de flection. 

It obvious and we must ask us can we apply the first condition for understanding the deflection of the strung instrument.

For me it is obvious what's wrong to do, the dead load condition.

Now I ask any one of you to answer and show proof that the dead loading condition produce the same deflection the string loaded instrument.

Pleas do this or accept my statement. Not answering mean to me "I don't know what's the differens".

enclosed you find the image Colin Gouhg together with G Stoppani produced when the loaded the center in their FEA. The end block remain at the same level.  The sound post hold telescoping function.

So just go ahead and convince me that I'm wrong. That's the best you can do!!!

 

2037624952_20141001Stopaniphasemovement20141001_00000.thumb.jpg.4bcc8a024d5982d47b2e7ba02e15459b.jpg

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When people don't understand they can explain anything. It's obvious they hide themselves when they are asked explain anything at all. It's a pity and not understandable that they replay on what is explained and shown to be proof. I don't understand why they take place/participate in any discussion at all. Please sharpen your state of mind!

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Sound posts on old Cremonese violins have moved thousands of km. But in relation to the galaxy they have bearly moved.

That's the new relativity theory of sound posts.

See, almost as smart as Einstein already :)

 

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Since there has been questioned whether the instrument in the center bend down or the end blocks are bend up consider whet you see. Bruce in his report show clearly that the center is forced down and I have said this is impossible. What we see on the two photos is the instrument laying on the table in the condition to be mapped. the back thus lay on the table. Now ask your self is it possible that the back is moving down producing the downward movement Bruce show in the report or is it the end blocks moving upward as the result must become by string load as I say. 

How Bruce is it possible that the end block remain at the same level and the center move down. This requires an increasing weight pushing down the table while the end blocks don not move. That's the condition in the climate chamber. Explain how the photo mapping condition can produce the condition in the climate chamber. All of us simple need reading your explanation. Yes I have said you did something wrong with the color mapping pictures. YOU MUST EXPLAIN so at least I can understand. It seem to me other also need.

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On 3/19/2021 at 7:55 PM, Marty Kasprzyk said:

Now when I meet a women at a bar I try to start a conversation by saying:  Do I come here often"

:lol:

22 hours ago, Peter K-G said:

Sound posts on old Cremonese violins have moved thousands of km. But in relation to the galaxy they have bearly moved. That's the new relativity theory of sound posts.

:)

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11 hours ago, reguz said:

Since there has been questioned whether the instrument in the center bend down or the end blocks are bend up consider whet you see. Bruce in his report show clearly that the center is forced down and I have said this is impossible. What we see on the two photos is the instrument laying on the table in the condition to be mapped. the back thus lay on the table. Now ask your self is it possible that the back is moving down producing the downward movement Bruce show in the report or is it the end blocks moving upward as the result must become by string load as I say. 

How Bruce is it possible that the end block remain at the same level and the center move down. This requires an increasing weight pushing down the table while the end blocks don not move. That's the condition in the climate chamber. Explain how the photo mapping condition can produce the condition in the climate chamber. All of us simple need reading your explanation. Yes I have said you did something wrong with the color mapping pictures. YOU MUST EXPLAIN so at least I can understand. It seem to me other also need.

 

Just clarify for me, please. Do you actually believe that when an archery bow is strung up it should remain straight? Because that's what you are saying.

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Hi Michael, When we tension the bow hair there is an action on the end of the bow stick. A moment of force is produced on the end of the stick that start bending. Part of the stick become stress depending of its stiffness. Less close the frog and more at the end part. This part of the stick may remain straight while other part don't. You can observe this with your eyes. Hope my answer is understandable.

So I'm not saying the stick remain straight. My excuse if I told wrong. 

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On 3/20/2021 at 10:08 PM, reguz said:

When people don't understand they can explain anything. 

The man said it himself! LOL. I look in the mirror and don’t see how big my nose is. Well, it’s the only nose I have and I can’t get rid of it. 

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Hi Don Noon. I wnt back and studie what was "discussed" on the tread https://maestronet.com/forum/index.php?/topic/346214-the-zuger-theory/

As fas as I can read nothing was discussed if the my assumption what the STL  produce is right or wrong. The University of Lund the two student doing their master dissertation just studied that and found out that my YES "theory" is correct. This does not mean that all or any other instrument not having STL as they are like mine will hav the same function. Not all all. But I'm sure that STLs as has been shown now have impact on the structural behavior. If you don't agree just verify why!  That we can have a discussion on but this far NOONE did. You may be the first one. What we could read was the comment given by "butcher" look at the figure 6 and 7 in the these. They show the sound post hold special function, DO NOT move. I have earlier shown a vector diagram that show proof. If you do not agree just say its wrong just as I say the colored figure of the Cannone are wrong. They are RIGHT when you hold the end blocks fixed but the instrument as YOU know very well does not have fixed end blocks. My research is not directed to give an answer howe your or any other instrument function . Its about the special structure of arching shape. The instrument plates in the these are thickness graduated and the out come of deflection is based on these conditions. What do we know from other instruments and their arching shape, your arching shape or any other, Little most probably nothing. As long as you can't verify you do not know anything. I have tried to find an answer on this and I believe I have done well! Criticize me if you like but say where I did wrong. Technical answers please!!

 

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I will recommend that the best response to someone who is more than a half-a-bubble off plumb, is to ignore them. Granted, a few rounds of  challenges and counter challenges may be needed to determine whether or not a person should easily be consigned to that category. And also granted, is that I have not always done the best or most efficient job of countering the whackos.

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30 minutes ago, reguz said:

Hi Don Noon.

(blah blah blah)

Technical answers please!!

Final summary:

The STL stuff looks like it could get an arching shape kinda like Cremnese arching, and probably work.

The gazillion diagrams and tons of words bhind the method do not appear to make technical sense from the standpoint of structural support or vibration that I am familiar with.

I have instruments to make for waiting clients.  Proving theories incorrect is not helping me, and usually is ineffective for those who firmly believe them.

End of discussion, ignore button pushed.

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1 hour ago, David Burgess said:

I will recommend that the best response to someone who is more than a half-a-bubble off plumb, is to ignore them. Granted, a few rounds of  challenges and counter challenges may be needed to determine whether or not a person should easily be consigned to that category. And also granted, is that I have not always done the best or most efficient job of countering the whackos.

  •  

 

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It may just be semantics, but I agree that the soundpost is a stationary element around which the violin bends. It is not pushed down by bridge force. That means that the end blocks will rise upward and rotate towards the centre.

I've looked at Reguz's violin geometry and it doesn't conform with mine as far as arching is concerned.

One thing I did take away from his work is the importance of the Double String Length Lines.

 

 

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8 hours ago, Dennis J said:

It may just be semantics, but I agree that the soundpost is a stationary element around which the violin bends. It is not pushed down by bridge force. That means that the end blocks will rise upward and rotate towards the centre.

Movement is always relative. Bending means movement in this case. It is not practical to measure movement of violin body parts relative to soundpost (even though computer could re-calculate the laser measurements according to that). SInce diagrams only plot movenet in z-axis (vertical) and not in all three dimensions yo need to set a plane perpendicular to that axis relative to which you measure displacement. This plane would be the xy plane and most logical choice is using bottom of neck heel and the lower bottom edge as typical natural support points when violin is rested in horizontal position.

Regarding reguz/zuger theory, it didn't make much sense to me either. discovery of STL in arching isn't anything surprising. Many such visual effects happen naturally in geometry just because of inflection of curvatures or similar properties of object. Just have a look at many graphs plotting prime numbers that show occurence of spirals or other shapes... no one defined primes because of their geomatrical properties, these things happen regularly in math, with no miracle or special intention.

Since the archings mostly follow outline shape I would be more surprised if something like that didn't apear somewhere especially when arching can be described relatively precisely with simple quadratic curves (parabolas, circles, ellipse). Connecting that to inentional special properties of structure or sound is overkill and has no solid basement unless someone really PROVES they DO. But that is homework for reguz/zuger, not for others to disprove.

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Hi HoGo at least you seem to understand that the sound post is not pushed down. That is what I have explained with a vector diagram. Now that you agree you also know that the end block at which the strings act are forced upward/inward, simply a type of rotation dependent on the structural stiffness of the violin body. When this rotation happen the bout shapes of the belly by compression starts buckling. "Buckling" is different from "bending" is happens when a column load forces the column to bend in one ore another direction. Since the "column" on the belly already has a curved shape it vill buckle outward. However the circumstances on the end point of the  column are different. On the end blocks they are "fixed" do not rotate while on the other end we find them free . On my internet site these circumstances are described. At the highest point of the curve the structure bent most, that's a normal behavior. Looking at the archery bow we have the strongest location where the bow is hold with your hand. What now important function does the STLs hold? Well as you van read in the these from the University these structures do not deflect. This means there arises a area on the bout shape that is surrounded with structure that has reacting condition. The these describe what the found and verify the figure I have shown that structure rotate on these STLs. Understanding this structural condition we can graduate the buckling area thinner. When that happens it of course will buckle more but what is important it will accumulate energy from the string load. The bout area bulge like blowing a balloon. Action on the string start a vibrating process and the bout areas function like springs releasing their stress condition. The whole violin body vibrate with a frequency different from the frequency on the string but on the bout area we find vibration we call modes condition. Finally back to your first line Denis J wrote. The sound post is stationary. This understanding confirm that the sound post does not move down and thus the colored images by Bruce Carlsson showing downward movement are wrong. It is very difficult making observation from the sound post. Bruce has given a number of places on the bout shape verifying that these locations become used in both the loaded and unloaded instrument. These locations are on moving structure and that's the reason why the color map is fault. Of course it is possible recounting the found deflection from those locations in relation to the not moving sound post but not understanding the condition on the sound post as the only not moving structure makes the result not understandable as it is shown and principally not usable. I see that your location is Slovakia. I had a project in Slovakia with the University in Zvolen. Unfortunately the professor, J. Cernecky, died not find a violin maker and died before we started any investigations.

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Whether or not the sound post moves is relative to your reference point.  There's no sense in trying to discuss something unless everybody uses the same reference point.

For example I'm sitting  here at my computer and I'm not moving at all relative to my chair, But relative to the center of the earth I'm moving pretty fast because the earth is spinning.  I'm moving even faster relative to the sun because the earth is orbiting around it and so on.  So it doesn't make any sense to argue whether or not I'm moving without specifying the reference point.

Even our basic measurements are relative to some reference for example a meter was 1/10,000,000 of the distance between the North and South poles, a liter was 1/1000 of a cubic meter, a kilogram was the mass of of one liter of water and so on.

But the big take away here is that it is easier to read something if spaces are made after a few sentences rather than having one long paragraph.

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