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vertical string pull on the soundboard (torque)   You are logged in as Guest
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Armando

Posts: 302
Joined: May 27 2005
From: Zürich, Switzerland

vertical string pull on the soundboa... 

Hi

Just came up with the issue of string torque.
I want to find out how many kilos of vertical force is to be applied on the soundboard to simulate the tension of a medium tension string set.
So there needs to be a calculation for the string torque.
But let's assume the bridge is 7mm high as it is supposed to be on a flamenco, what would be the vertical pull in kilos? I mean this is a very crucial information. It should be known.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 19 2020 14:26:23
 
RobF

Posts: 947
Joined: Aug. 24 2017
 

RE: vertical string pull on the soun... (in reply to Armando

I don’t know if you could call having the information crucial or not, or else it would already be pretty common knowledge, I suppose, but you could probably arrive at a rough estimate empirically by measuring the vertical deflection of a top under load and then comparing the result with the deflection of a sample top of similar thickness and characteristics after it is loaded down with a known weight placed in the bridge area. The sample top would have to be braced in the same manner and supported along its edges, however, perhaps by a set of sides that have been bent. Heck, maybe it is common knowledge and I’ve just never came across it. My empirical method might be tainted if the deflection due to load isn’t a linear response, however, or maybe it’s better to say the results will only be only meaningful if the deflection remains in its linear region.

Actually, now that I think about it, it probably is easier just to ask one of the wizards on here to do the math, like you just did, lol. It might be as simple as multiplying the sum of the stated string tensions by the fraction defined by the string height above the top divided by the string length, but don’t know. Maybe Konstantin or Richard will step up to the plate and come up with something more meaningful. But, would you really need anything more than a ballpark figure?

P.S. I take it you are wanting to pre-calculate the top rise so you can work out neck angle, or maybe something along those lines (I’m still trying to figure out why this info is crucial). Some people will either simulate a load or actually string the guitar when setting up, and I guess that’s the most accurate way, as it includes neck rise and relief, which any formulae will also have to do. I just allow for a rise of approximately 0.2mm at the 12th, so I set the guitar up with lower action to account for that. But maybe that’s not why you want the the information.
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 19 2020 15:37:39
 
JasonM

Posts: 1565
Joined: Dec. 8 2005
From: Baltimore

RE: vertical string pull on the soun... (in reply to Armando

I wonder if Trevor Gore’s book would have that info? I flipped through a friends copy and saw a lot of calculus
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 19 2020 16:32:51
 
RobF

Posts: 947
Joined: Aug. 24 2017
 

RE: vertical string pull on the soun... (in reply to JasonM

quote:

I wonder if Trevor Gore’s book would have that info?

It probably does, I just figured it would be cheaper to let Konstantin or Richard (or you) do the heavy lifting. I’d look into it, but I’m afraid there might be square roots involved, and I’ve sworn off that stuff, having decided to live a life based on intuition, hearsay, and mumbo-jumbo.
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 19 2020 18:17:34
 
TonyGonzales84

 

Posts: 78
Joined: Apr. 23 2020
From: San Diego, CA

RE: vertical string pull on the soun... (in reply to Armando

Everybody in the water!

Note: I have edited and corrected my original response, to that shown here. I apologize if you have read my initial response and were confused by it; it would have been correct only in the case of an antique type of tie-block, prior to luthiers/guitarreros including a separate saddle.

Armando,

1) Statically, the net vertical load due to the strings can be calculated, first, by calculating the string turning angle, A. A is the Arc Tangent of the quotient of the difference in height that the saddle sits above the tie-block holes, a (a is the numerator), and the distance forward of the front end of the tie-block that the string turns down from the top of the saddle, b (b is the denominator): Arc Tangent (a/b) = A. (I apologize for not showing a sketch - I am not near a printer/scanner, nor do I currently have good sketching software.)

Next, take the sine of A and multiply it by the string tension F. F * sine A = Net Vertical Force. This force pushes down (against) the top.

2) The static torque applied to the top, by the strings via the saddle/bridge assembly, also causes vertical displacements of the top.
3) What type of simulation are you intending to perform? It's often a challenge to actually set up and perform a test that tests what you are attempting to test, and not a (possibly closely related) phenomenon.

The above is the Reader's Digest version. Hopefully, this is not the place where Mr. T comes in with his, "get ready for the pain!" Addressing each of the three, numbered points, in slightly expanded form:

1) The vertical load (against the top) changes when the strings are set into vibration, due to these vibration induced dynamic vertical loads. Richard Jernigan has linked an interesting and enlightening article by Alan Carruth, here (excellent work in investigating the dynamic vertical loads, etc):
http://alcarruthluthier.com/Downloads/stringTheory.pdf

The vertical loads are dynamically present as reactions to the strings's transverse (vertical) vibrations.

The static vertical loads, due to the torque caused by the strings, are a couple, reacted by the bridge, which then must be reacted by the top. The part away from the soundhole, which is trying to be pulled off, is exactly matched by the part towards the soundhole, which is being pressed into the top. The values of these static loads change during string vibration.

I recommend caution in attempting to simulate such dynamic loads, overlaid on the static load caused by the saddle turning angle, as static loads: this can be self-defeating, especially in regards to the actual physics and design/construction problems and possible solutions. Please refer to Mr. Carruth's paper for more discussion on the vertical loads.

2) The vertical displacements caused by the applied torque also affect the top in buckling, between the bridge and soundhole (I believe that, statically, it is (somewhat?) relieving), actually inducing a top buckling load on the other side of the bridge.

A guitar is a structure that is designed for (by) stiffness considerations, as apposed to a structure being designed by strength considerations. For example, the top probably doesn't want to be designed to buckle anywhere (although it might be interesting to some, to design and build a guitar (top?) lightly enough that it would be statically stable against buckling, but that might temporarily buckle in certain, well-understood dynamic modes); also, think of the pre-strung tone tuning performed by luthiers; in Mr. Carruth's paper, he discusses a 4 kHz mode of longitudinal string vibrations, that he recommends slightly lengthening the scale in order to avoid resonant effects caused by said modes. Designing for stiffness requires much finesse and attention to detail in, for example, local and minute structural deflections, and scares the hell out of many engineers!

As to one of the kernels in your original post, the static torque applied by the strings, calculated at the bridge-to-top joint is just the height of the strings, h, multiplied by the total force of the strings (can be looked up on several manufacturer's sites), F (the same F as discussed above). Remember here, that, the bridge and top also have to react (withstand) the longitudinal load of the strings, F: The bridge-to-top glue joint has to not fail due to this shear load, and the top, between the bridge and soundhole has to not buckle.

3) Rereading your original post, it seems you wish to apply a (static) vertical load to simulate the torque. I don't fully understand what one might gain from this test: it does not fully simulate a guitar, as a guitar actually functions. Much or all of the foregoing might go into planning a test that would simulate the way a guitar actually functions.

Best regards, and I look forward to hearing your thoughts!

Tony

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Tony
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 19 2020 22:09:03
 
TonyGonzales84

 

Posts: 78
Joined: Apr. 23 2020
From: San Diego, CA

RE: vertical string pull on the soun... (in reply to Armando

I believe break angle is what I call "turning angle."

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Tony
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 20 2020 18:08:53
 
Ricardo

Posts: 12668
Joined: Dec. 14 2004
From: Washington DC

RE: vertical string pull on the soun... (in reply to TonyGonzales84

I played a guitar with break angle =0 and the sonic and feel differences before and after (After repaired string holes allowing for some minimal break angle) where negligible. In fact the reason for the repair was that lowering the saddle below the “break angle =zero” level allowed an unwanted buzz or rattle to be produced from a strong pluck. String holes were filled and redrilled. It was surprising that the guitar output was not affected by an increased break angle.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 20 2020 19:25:47
 
Richard Jernigan

Posts: 3012
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: vertical string pull on the soun... (in reply to Ricardo

A few years back break angle was a hot topic for discussion. People were saying that going to a 12'hole bridge was a big deal.

I had my doubts. As long as the string doesn't slip on the saddle or lift off of it, the break angle makes little, if any, difference.

It wasn't too hard to find coefficients of friction for nylon and bone. The forces were measured by Al Carruth.

My calculations showed that any reasonable six-hole biridge would do the job. Surprise, surprise! Instrument makers have been getting it right on guitars, vihuelas and lutes for centuries.

I can't find my calculations any more. Richard Bruné says he prints them out and hands them to customers. Maybe they want 12-hole bridges? I've seen pictures of 18-holers(!). I have one guitar with a 12-hole bridge. I didn't ask for it, it's just the way Abel Garcia makes most of his instruments.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 21 2020 1:01:01
 
Armando

Posts: 302
Joined: May 27 2005
From: Zürich, Switzerland

RE: vertical string pull on the soun... (in reply to TonyGonzales84

Thanks for the detailed information.
I'm not really a math guy and would love to have just a tool where
to enter the variables and the thing would spill out the result.

The thing is that i'm not building nearly enough guitars to get it in my
fingers when the stiffness of a top is just right.
So it would be helpful to have a point of reference that could
be measured in the way described. (Clamp the top into a frame
and hanging weight on it?

I know from my previous guitars that my tops always ended up
on the stiff side. Also the attempt to work wirh chladni patterns
was an intersting approach, but it did not really help me to get my top any better.
So, before building another guitar with a too stiff top, i'd like to
learn how to find out the deflection point of the top.
When will it start to deflect under string tension?

There's no other way to know in my opinion other than to know the
vertical pull.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 26 2020 2:33:28
 
Tom Blackshear

 

Posts: 2188
Joined: Apr. 15 2008
 

RE: vertical string pull on the soun... (in reply to Armando

Armando, you may have to receive some training under a builder who has already achieved a correct top tension for his work. And then work around his model to achieve your own creation.

If you haven't already figured out the graduation for the top thickness and how to balance the harmonic size for the horizontal bars then you are going to get confused without someones help to get that straight.

Because all the rest would be variables of the tweaking process until you reach a synergistic end result of harmonic balance. No disrespect.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 27 2020 2:03:15
 
Stu

Posts: 1843
Joined: Jan. 30 2007
From: London (the South of it), England

RE: vertical string pull on the soun... (in reply to TonyGonzales84

Genuine question.
Is this stuff/knowledge necessary?

What would be the downsides of not going through all of this?? Or maybe I mean.... what is the benefit of knowing this/being able to simulate vertical tension?
  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 27 2020 18:47:21
 
RobF

Posts: 947
Joined: Aug. 24 2017
 

RE: vertical string pull on the soun... (in reply to Armando

quote:

I'm not really a math guy and would love to have just a tool where to enter the variables and the thing would spill out the result. The thing is that i'm not building nearly enough guitars to get it in my fingers when the stiffness of a top is just right

Here’s a way to do a deflection test, no math required. Matter of fact, the only numbers you really need are the deflection measurements themselves, which you will want to start to record for each guitar. The weight in the picture is arbitrary, although it wouldn’t hurt if it was something easy to replicate, such as 500g, 750g, or 1kg. But, honestly, it doesn’t matter as long as it stays constant. The measurements taken from one top to the next provide the points of reference.

Three pictures should be enough to tell the story. They should be regarded solely as an example of one way you can go about helping your fingers read a top. A lot of information can be derived from a measurement such as this. But the point is, you don’t need formulae, computer programs, or a degree in Engineering or English Literature to build a good guitar. Just let common sense rule the day.

I won’t go any deeper, this should get you started, and you can custom tailor the methodology and how you treat the data to suit your own needs. I hope this is of some help. Cheers!







Images are resized automatically to a maximum width of 800px

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  REPORT THIS POST AS INAPPROPRIATE |  Date Jul. 28 2020 23:49:50
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to Armando

You’re not gaining much leverage on the saddle with severe break angle.

Al Carruth did a few subjective and quantitative tests. Anything after 7 or 8 degrees break angle is doing most of the needed work. After 12 or 13 degrees the benefit or return vs. angle steepness has diminishing returns.

I think Gore data something slightly different, I’ll check.

But for nylon strings ever since Al did his tests about 15 years ago I’ve not used steep break angles. I’ve not noticed a problem.

It’s a thing many people over think, or think through because it’s interesting, but it’s not a crucial thing to have a deep mathematical understanding of to make a super good guitar.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 6 2020 11:06:04
 
Richard Jernigan

Posts: 3012
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: vertical string pull on the soun... (in reply to estebanana

As long as the string doesn't slide on the saddle, or lift off it, and the saddle is firmly seated in the bridge slot, break angle makes no difference to the torque applied to the top. The height of the saddle above the soundboard determines the torque applied to the bridge, the details of the bridge footprint on the soundboard govern how this torque is applied to the top: freshman physics.

The makers of plucked instruments have been getting it right for centuries, if not millennia.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 6 2020 18:36:01
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to Armando

Long scale - don’t fart around with 650 scales anymore. Make flamencos with 26” and over scales 665 mm - don’t cater to the new world whiners who think their precious hands will be destroyed with higher tension. Tell the snivelers to use a cejilla in the first fret until they can play the open scale. Take no prisoners, do not give in.

Long string lengths drive the top better. The important part is the strength along the grain, if your tops are too stiff along the grain sand along the grain a bit before you glue the bridge on.

Long scale, use five braces and focus them under the bridge and leave the bouts open. Stiffness aling the grain, medium bridge weight, not too light, definitely not too heavy. About 20 grams with a longer scale. Stiffness along the grain is more important for activating the modes that generate the upper frequencies that are pertinent to good tone and projection. The open unbraced lower bouts encourage the side to side teeter totter movement of the cross di pole mode, that mode combo gives flamenco guitars a lot of substantive tone, the growly husky sound is partially developed by a slightly over active cross dipole.

Restriction to the full unidirectional movement of the bridge by a stiff top along the grain will redirect the bridge movement to the loosest direction. If the bridge can’t move as much in the center axis toward the neck and tail, some of that energy will be picked up and redirected into the cross pole direction.

Think of the top like a crucifix- the vertical beam is the long mono pole or stiffness along the grain, the cross bar is the cross di pole axis and literally the bridge. Keep the long beam stiff and allow the cross beam to flap like bird’s wings.

Too stiff along the grain? Can’t figure it out? Use three strong central braces under the bridge and two slighter braces at the outer edges of the bridge. ( look At Brune’s 1951 Barbero drawing) then use a long scale 660 and longer up to 665mm

And to reiterate the most important point, slap the idiots who want short scales unless they show up with a note from a doctor saying they are clinically dead.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 7 2020 2:16:11
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to Armando

God damn that was a beautiful rant post. I feel good!

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 7 2020 2:56:00
 
Echi

 

Posts: 826
Joined: Jan. 11 2013
 

RE: vertical string pull on the soun... (in reply to Armando

quote:

God damn that was a beautiful rant post

+1
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 7 2020 10:19:07
 
Stu

Posts: 1843
Joined: Jan. 30 2007
From: London (the South of it), England

RE: vertical string pull on the soun... (in reply to estebanana

😧
Well.... That's disheartening. 😄

I'd just come to terms with my mistake on no.2.

I cut my heel for a 650 scale by mistake! 😭
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 7 2020 21:28:28
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to Armando

With 2mm compensation you get 652 string length, sell it to some whacko who plays classical music and drinks lemonade in their beer. Here ya go Sheila, a short scale for ya

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 8 2020 13:58:31
 
ernandez R

Posts: 351
Joined: Mar. 25 2019
From: Alaska USA

RE: vertical string pull on the soun... (in reply to Armando

Stu & Stephen

My last two builds both are 666mm built concurrently with the tops sliced off next to each other and all other woods cut from the same pieces accordingly.

Couple observations. One is my best, well rounded with a good low end grawl and nice trebles. This one the top lifted the usual amount under tension.

The other is a beast. A whole different magnitude better. After about six months strung up and a fair amount of playing, both still in the white cause I still can't get in the shop yet with my buggered up foot, i notice I've got about 5mm at the 12 fret. Hmm. I spend some time thinking about how the neck could have moved that much... still under some pain meds and mind **** nerve blockers. After I kick the pill habits I notice the neck is mostly were it was all along. The top had lifted a lot. She might end up in the wood stove... Then again I might get medieval with her, slice the neck off leaving the fretboard connected, then reattach accordingly...

So now I'm wondering, was the top too thin, the braces too thin, plenty of other variables and I'm not much of a note taker... What is the variable that made her so much better then her sister?

Less then ten guitars in and thinking one can use all the math and measuring tools out there and one still needs to build a hundred guitars using the same mold and woods etc like the old masters to get the feel for where one needs to aim to get an output. I don't know, failing for the words.

Need to add that I'm not using a standard bracing but a radial system half copied and half the product of my mind...


HR

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I prefer my flamenco guitar spicy,
doesn't have to be fast,
should have some meat on the bones,
can be raw or well done,
as long as it doesn't sound like it's turning green on an elevator floor.

www.instagram.com/threeriversguitars
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 8 2020 19:51:34
 
ernandez R

Posts: 351
Joined: Mar. 25 2019
From: Alaska USA

RE: vertical string pull on the soun... (in reply to Stu

Stu,
Save the short neck for your next "Clasical " build and make up a new one for your Falmenco.

And to be honest, did the same with my last two necks, they are hanging from the ceiling and will both make a fine Clasical some day.

Wen I remade them they were better in every way and took less time.

HR
quote:

ORIGINAL: Stu

😧
Well.... That's disheartening. 😄

I'd just come to terms with my mistake on no.2.

I cut my heel for a 650 scale by mistake! 😭


_____________________________

I prefer my flamenco guitar spicy,
doesn't have to be fast,
should have some meat on the bones,
can be raw or well done,
as long as it doesn't sound like it's turning green on an elevator floor.

www.instagram.com/threeriversguitars
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 8 2020 19:57:14
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to ernandez R

How’s your seasonal RH fluctuation and it’s effect on shop space?

How’s the lower transverse bar and the one under the fingerboard extension?

Usually thin tops bulge up behind the bridge and scoop under in front - provided those two braces are structural components holding that upper bout with full integrity

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 9 2020 3:18:06
 
Tom Blackshear

 

Posts: 2188
Joined: Apr. 15 2008
 

RE: vertical string pull on the soun... (in reply to estebanana

quote:

Usually thin tops bulge up behind the bridge and scoop under in front - provided those two braces are structural components holding that upper bout with full integrity


Steve,

I realize this has been said before but perhaps we have a few new members that need to have this repeated. I know I mentioned it when trying to describe the top function on the Reyes model. Thin tops will normally pull up below the bridge and go a little concave in front. The old Spanish masters used to say the guitar was not good unless it bent a little between the bridge and sound hole.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 9 2020 4:26:31
 
JasonM

Posts: 1565
Joined: Dec. 8 2005
From: Baltimore

RE: vertical string pull on the soun... (in reply to Tom Blackshear

Tom, do you also have this opinion , or just stating what the old masters used to say ? Don’t Condes have thick /or ridged tops which do not cave in in front of the bridge?


Rob, that’s a cool looking top!
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 9 2020 16:16:37
 
RobF

Posts: 947
Joined: Aug. 24 2017
 

RE: vertical string pull on the soun... (in reply to JasonM

quote:

Rob, that’s a cool looking top!

It’s part of my ever growing collection of tops in search of guitars.
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 9 2020 18:56:24
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to JasonM

It works both ways, because guitars are mysterious animals.

Some tops dip in front of the bridge and some don’t and still work. Use a ruler in front of the bridge and behind the bridge to get a reading. Sometimes what looks arched is flat in front and slightly arched behind- in the space of an wide bridge.

There are many iterations to how the top to bridge area gets sculpted due to string pull vs. top strength along the grain and bridge flexibility. Just because a thin top characteristically tends to dish in between the bridge and sound hole does not mean that it’s the only sculpture of the top that is working.

Dished tops are a three edged sword. 1. It’s light and high performance in one sense. 2. It’s like a Amodovar film, on the verge of a nervous breakdown. 3. It may or may not be squishy in that dished area. If the dish is happening and the area is ‘hard’ and the braces are sectioning off the area and allowing it to be depressed, but still hard and stiff it’s going to function better in the way string energy will activate higher frequency modes in that region. The B flat trough D# on the high E string. A lot of that support in those frequencies comes in part from that region between the bridge and sound hole. If that area is dished but still stiff enough it’s good. If it got sculpted into that dished shape because the stiffness along the grain is _much too weak_ then trouble.

There’s a line between dished out in front of bridge, but still functioning, and dished but too weak. Where that line develops from a practice standpoint is difficult to determine, it’s a fine line.

The Redgate model classical guitar with lattice bracing, or whatever he throws in there, is predicated in the idea that the top is light and thin and will be sculpted into that dished shape. So the intention was to allow a thin top to be braced to mold it into that wave shape, but make it super stiff. It seems to work. It’s a good one to think about as a thought experiment, but you wouldn’t get a very flamenco sounding guitar if you build it as he builds that wave model. He told a friend of mine he’d rather build flamenco guitars, but he makes a good living building guitars that sound like Bosendorfer pianos.

Condes’ characteristically have a different zeitgeist- slightly heavier bridge and top, fairly long scale and often no braces in the lower bout between the bridge and the outside rim of the top. They have a different tempo of attack than a guitar with dished out top. But all that is subtle subjective stuff that needs to be parsed out one guitar at a time. But conde guitars generally work in the principal that you don’t want the top to sculpt into a wave along the grain.

Here’s what can typically happen to the Conde approach, the top dishes between the edge of the bridge arm and the side of the lower bout. If you hold a straight edge across the top behind the bridge, you’ll see a slight arc where the seam of the bridge meets the top and then it (may or may not ) dip into a slight valley between bridge and edge of guitar. If you exaggerated that line it would look like swell with a shallow trough on either side.

Some guitar tops hold an arch in every direction, the peak of of the dome usually under the bridge. And some guitars express a wave shape that can be oriented either across the grain or with the grain. If the wave is expressed along the grain it looks like a bulge behind the bridge and a dish in front of the bridge. If expressed across the grain it usually looks like the bridge is in a hill with slight troughs on either side.

All these expressions of stress work or are tolerable to the guitar and it will function, be stable and sound good. But there is a fine line to when these expressed sculpted Stresses become liabilities. Safe to build the guitar that holds an arch in every direction and eventually through the course of your building practice make forays into the wave shape styles or intentions.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 10 2020 3:09:57
 
JasonM

Posts: 1565
Joined: Dec. 8 2005
From: Baltimore

RE: vertical string pull on the soun... (in reply to estebanana

quote:

t’s like a Amodovar film, on the verge of a nervous breakdown.
... I only saw Habla con Ella many years ago. It was indeed a typical depressing art film.

It’s mind boggling how much info the maestro knows from the grasshopper’s perspective. Thanks for the info. It’s never as easy as a one variable explanation is it?!
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 10 2020 23:31:01
 
estebanana

Posts: 7999
Joined: Oct. 16 2009
 

RE: vertical string pull on the soun... (in reply to Armando

Matador is a great film. And I like the ones with Penelope Cruz. I find them oddly stimulating.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 11 2020 12:37:20
 
Tom Blackshear

 

Posts: 2188
Joined: Apr. 15 2008
 

RE: vertical string pull on the soun... (in reply to JasonM

quote:

Tom, do you also have this opinion , or just stating what the old masters used to say ? Don’t Condes have thick /or ridged tops which do not cave in in front of the bridge?


I've studied 1950's and 60's Conde flamenco guitars with both thick and thin tops. The thickest top was a 1952 at about 3/32" on a Sobrinos de Domingo Esteso flamenco. the thinnest was a 1968 at a little over 1/16" with the same pattern.

The big difference between the different thicknesses was how the fan braces were treated with different sizes. The thicker tops had slightly thinner braces.

I think the ongoing scenario is always going to be that the builder tries to construct a guitar to fit the player's style, yet some builders just let it fly and see where it goes.

_____________________________

Tom Blackshear Guitar maker
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 11 2020 13:06:50
 
RobF

Posts: 947
Joined: Aug. 24 2017
 

RE: vertical string pull on the soun... (in reply to Tom Blackshear

quote:

The big difference between the different thicknesses was how the fan braces were treated with different sizes. The thicker tops had slightly thinner braces.

Hi Tom, were you able to measure the size of the lower bouts? Did the thick topped guitars have larger areas? Both Condes I’ve owned had thick tops but also large lower bouts, in the neighborhood of 14 3/4”.
  REPORT THIS POST AS INAPPROPRIATE |  Date Aug. 11 2020 16:25:25
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