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  #46  
Old 12-14-2017, 08:16 PM
charles Tauber charles Tauber is offline
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Originally Posted by Otterhound View Post
If bridge pins are pulling upwards because of anchoring issues , what are they anchored to ?
"It's turtles, turtles all the way down."

Indulge me with a "thought experiment".

1.Take a wooden board and drill a hole in it. Insert into that hole a peg that is smaller in diameter than the drilled hole. Turn the board upside down. What happens to the peg? It falls out, right?

2. Take a wooden board and drill a hole in it. Insert into that hole a peg that is exactly the same diameter as the drilled hole. Turn the board upside down. What happens to the peg? If falls out, right?

3. Take a wooden board and drill a hole in it. Insert into that hole a peg that is slightly smaller in diameter than the drilled hole. It will be a light press (interference) fit. Turn the board upside down. What happens to the peg? It does not fall out, right? Why not? The interference causes compression of the wood of one or both of the hole and peg: forces that act perpendicular to the mating surfaces - in this case in the direction of the longitudinal axis of the peg/hole. There is zero force that acts along the longitudinal axis of the peg/hole.

Repeat the same three step "experiment" with a tapered hole and tapered peg, for argument 3 or 5 degrees of taper.


Given that a properly seated, fully tensioned string can have its bridge pin removed from its hole while the string remains in its hole, what effect does the string and its forces have on the bridge pin? [Hint: tipping moment.]
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  #47  
Old 12-14-2017, 08:24 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by Otterhound View Post
What are the negatives ?
First, if you had to replace one string, you have to loosen all of them to gain access to the sound hole. Second, you pretty much have to string the guitar by Braille, which might not be that efficient at a gig; and it would make the guitar impractical for any serious gigging. Third, there are so many guitars out there that sound absolutely amazing, that have bridge pins, or a convenient rear-loading string-through bridge, or one of the top-anchored solutions; it would be difficult to prove what positive effect to the voice of the guitar the design offers. Fourth unless you also sell refrigerators to eskimos, this would be a tough sell, even for a well known, established luthier.

That said, I'm not opposed to the concept; I think it's pretty cool. I just don't find myself moving in this direction (though I too have a concept that is pretty off-beat). You seemed to have carved yourself a nice little niche with this and hope it gains some traction for you. I also think it would be fun to experiment with different string plates to see how it affects tone; such as bone, Brazilian rosewood, carbon-fiber, etc...
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  #48  
Old 12-14-2017, 08:36 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by Otterhound View Post
If bridge pins are pulling upwards because of anchoring issues , what are they anchored to ?
I hazard to guess Ned is referring to the anchoring of the ball end of the string. If the ball end is not properly seated, and a likely ill-fitted pin (or one not fitted to the particular hole) is forced in, then tightening of the string can force it to push the bridge pin out. This can be the thicker wound part of the string getting jammed into the slot of a slotted pin, or the ball end catching the end of the pin, etc. Regardless, this is likely also causing some damage to the bridge plate. A lot of this I feel is do to careless stringing rather than design. But when I slot my bridge pin holes, I make it just snug that I can, with a little tug, feel the ball end seat against the bridge plate and rest against the pin.
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  #49  
Old 12-14-2017, 09:22 PM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by Otterhound View Post
If bridge pins are pulling upwards because of anchoring issues , what are they anchored to ?
Strings pull upwards due to ball end anchoring issues when the bridgeplate and/or holes and/or taper and/or bridge pins are ill-fit or ill made.

When strings and their subsequent ball ends pull up like this, it will often move the bridge pin (ie: "pull" the bridge pin) upward in its hole. There is more friction and "grab" between the ball end and compression-dented bridge pin than there is friction between the bridge pin and inside of the bridge pin hole. So, hence, up slightly slides the bridge pin.

Even during this situation, bridge pins do not really pull up on the bridge, because there is not enough grab or friction to make any consequential upward force.
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  #50  
Old 12-15-2017, 06:55 AM
hat hat is offline
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ok, so here's a crazy thought. What if the strings are anchored by passing through holes in the back? Or possibly a keyslot plate mounted to the back, much like a bridge plate? Then, they pass from underneath through the bridge, and over the saddle. This way, they drive both the top and back!
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  #51  
Old 12-15-2017, 07:48 AM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by hat View Post
ok, so here's a crazy thought. What if the strings are anchored by passing through holes in the back? Or possibly a keyslot plate mounted to the back, much like a bridge plate? Then, they pass from underneath through the bridge, and over the saddle. This way, they drive both the top and back!
Then you will be putting pressure and strain on the back that doesn't exist in present designs, so bracing would require rethinking and alteration due to this new force.
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  #52  
Old 12-15-2017, 08:06 AM
Otterhound Otterhound is offline
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Quote:
Originally Posted by hat View Post
ok, so here's a crazy thought. What if the strings are anchored by passing through holes in the back? Or possibly a keyslot plate mounted to the back, much like a bridge plate? Then, they pass from underneath through the bridge, and over the saddle. This way, they drive both the top and back!
Try it man !
Let us know what you find .
Bend the freaking rules because this is where and how we learn .
I must admit that this sounds similar to something else out there .
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  #53  
Old 12-15-2017, 08:22 AM
hat hat is offline
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Try it man !
Let us know what you find .
Bend the freaking rules because this is where and how we learn .
.[/QUOTE]

Exactly. You can't get anywhere if you sit on the same spot forever!
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  #54  
Old 12-15-2017, 08:34 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by hat View Post
ok, so here's a crazy thought. What if the strings are anchored by passing through holes in the back? Or possibly a keyslot plate mounted to the back, much like a bridge plate? Then, they pass from underneath through the bridge, and over the saddle. This way, they drive both the top and back!
You'll need longer strings than those typically commercially offered.
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  #55  
Old 12-15-2017, 08:45 AM
Otterhound Otterhound is offline
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Quote:
Originally Posted by LouieAtienza View Post
First, if you had to replace one string, you have to loosen all of them to gain access to the sound hole. Second, you pretty much have to string the guitar by Braille, which might not be that efficient at a gig; and it would make the guitar impractical for any serious gigging. Third, there are so many guitars out there that sound absolutely amazing, that have bridge pins, or a convenient rear-loading string-through bridge, or one of the top-anchored solutions; it would be difficult to prove what positive effect to the voice of the guitar the design offers. Fourth unless you also sell refrigerators to eskimos, this would be a tough sell, even for a well known, established luthier.

That said, I'm not opposed to the concept; I think it's pretty cool. I just don't find myself moving in this direction (though I too have a concept that is pretty off-beat). You seemed to have carved yourself a nice little niche with this and hope it gains some traction for you. I also think it would be fun to experiment with different string plates to see how it affects tone; such as bone, Brazilian rosewood, carbon-fiber, etc...
Your number 1 is viable purely from a convenience point . Of course , I can't remember the last time I broke a string while playing , but that's just me .
Your number 2 is questionable . I had the very same concern until I strung one up . As long as there was 1 string in place or more , my hand found locating the pass hole very easy . Could have done it with my eyes closed .
Your number 3 combines 2 things . Selling a new design in any field is challenging . This is a given . Concerning voicing is interesting since my concept can be applied to any existing standard pin bridge without modification , back to back comparisons using variations on my concept should be seamless and devoid of harm . The only thing that will suffer are strings .
I have 3 different pin bridge guitars here that I will be using for test mules going forward as well as the original that simply lacks the ream to accommodate pins .
Your number 4 returns back to the first of my comments on your number 3 . Full circle .
On thing to consider is that my intent is to utilize a plate material that will conform to any variables in the shape or curvature of the top . I do not intend to have my plate shape or mold the built in shape of the top . Thus the 1/8" thickness .
In the end you are correct that it will be fun experimenting further with this .
The size of the footprint and shape of the plate may also have an effect .
A larger plate or smaller plate will distribute load differently as well as placing more or less mass at a different location .
Let's say that you would like more mass on the bass side as well as less on the treble . It may be possible to do this with the shape of the plate . You may even desire to split the plate in some fashion for a desired effect .
Outside of the box is where we learn .
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  #56  
Old 12-15-2017, 08:57 AM
hat hat is offline
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Quote:
Originally Posted by charles Tauber View Post
You'll need longer strings than those typically commercially offered.
yea, that would be the issue. But, theoretically , since the back is already braced basically in a ladder bracing form, all that would need to be added would be a 'backplate' mimicking the bridgeplate to help reinforce the back. Possibly also a couple of soundposts to help couple the top and back......hmmmm
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  #57  
Old 12-15-2017, 09:06 AM
MrHooligan73 MrHooligan73 is offline
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I like them painless. Very useful and saves time. Never had one fail in 30 years. Interesting to read others thoughts though.
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  #58  
Old 12-15-2017, 09:14 AM
LouieAtienza LouieAtienza is offline
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Originally Posted by Ned Milburn View Post
Then you will be putting pressure and strain on the back that doesn't exist in present designs, so bracing would require rethinking and alteration due to this new force.
I think along with the pulling force up on the back, comes a pulling force down from the top. I don't see it as too much of an issue for the back as it is typically arched, and can be made stiffer to create a more "reflective" and "projective" back. The questions lie more with the top - I suppose there will be issues as far as strengthening the top to absorb the pulling force down, while keeping the frequency of the top low, or at least low enough to produce a voice that one may find pleasing.

I did once develop a method for "decoupling" the effect of shear force on the bridge from the strings without anchoring the strings to the tail end, though never tried it on a flat-top guitar.
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  #59  
Old 12-15-2017, 11:39 AM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by LouieAtienza View Post
I think along with the pulling force up on the back, comes a pulling force down from the top. I don't see it as too much of an issue for the back as it is typically arched, and can be made stiffer to create a more "reflective" and "projective" back. The questions lie more with the top - I suppose there will be issues as far as strengthening the top to absorb the pulling force down, while keeping the frequency of the top low, or at least low enough to produce a voice that one may find pleasing.

I did once develop a method for "decoupling" the effect of shear force on the bridge from the strings without anchoring the strings to the tail end, though never tried it on a flat-top guitar.
There are 2 problems that come to mind immediately. The coupling of back to soundboard under pressure of strings will inhibit soundboard's diaphragmatic vibration. Second, is what I mentioned above. Structurally the forces become distributed much differently on the instrument's body, and without careful rethinking and redesigning, there will be body deformation.
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  #60  
Old 12-15-2017, 12:05 PM
Rodger Knox Rodger Knox is offline
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Quote:
Originally Posted by hat View Post
ok, so here's a crazy thought. What if the strings are anchored by passing through holes in the back? Or possibly a keyslot plate mounted to the back, much like a bridge plate? Then, they pass from underneath through the bridge, and over the saddle. This way, they drive both the top and back!
No, they provide a mechanical couple between the top and back. That will reduce the power of the main air resonance and alter it's frequency.

Quote:
Originally Posted by hat View Post
yea, that would be the issue. But, theoretically , since the back is already braced basically in a ladder bracing form, all that would need to be added would be a 'backplate' mimicking the bridgeplate to help reinforce the back. Possibly also a couple of soundposts to help couple the top and back......hmmmm
Now you've got a solid mechanical couple between the top and back. That eliminates the main air resonance, and forces the main top and back resonance to the same frequency. So instead of three strong resonance frequencies, you've got one that's not as strong as any of the three and probably higher in pitch than any of the three.

There are no good ideas in this thread, but feel free to try the string through and sound posts. You might like a guitar with no bass response. I'm done here.
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