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I'm currently trying to design a bridge. I have a question about the break angle - is there something like an ideal break angle?

I know that a greater break angle potentially drives the top better (which is one reason why you rarely see tail pieces on flat top acoustics).

But are there diminishing returns when increasing the break angle, or even detrimental effects? Or would a 90 degree break angle be every luthiers dream?

Basically any info about break angle would be greatly appreciated.

thanks, Christian

realisticly you will be looking at something between 20-30 degree brake angle from horizontal to the saddle break edge.. Too steep and the string will want to ride down the saddle. Too shallow and the string will want move too easily on the saddle. you also want to be sure the string is not contacting the bridge wood between the pin and the string slot you file into the bridge.

90 degree could never be possible as the sting would be in contact with the back side of the saddle

Could you explain the break angle for us newbies out there? Is it the slope of the top face of the bridge towards the fretboard?

in truth the slope of bridge has little to do with the break angle. the break angle is the angle formed by string as it leaves the saddle to enter the trapment of string ball between the pin and bridge plate. or in shorter words the angle of the string on the back side of the saddle. How close the pins are to the saddle affect this angle the most of any bridge geomatry. The closser the pins the sharper the angle.

Great, thanks Michael. 20-30 degree is the kind of answer I was looking for.

The 90 degrees was more of a theoretical question...

Edward, as I understand it, alpha is the break angle:

Martin looks for about a 45 max degree break angle. The important thing to note is that it isn't all about break angle ,the total height is also important. I try to keep it between 35 to 45 degrees. If you look at a martin bridge , the pins on the standard series is parallel to the front of the bridge , this angle will make each string have a different break angle , and on the 15 series on down the pins are drilled parallel to the saddle , and you have a static break angle at the strings.
You can adjust the break angle by cutting slots and ramps into the bridge. If you do the math of the string pull and angle , at 45 degrees you have an even amount of pressure pushing down on the saddle and pulling on the plate. This is considered by some to be optimum. You can figure the forces by using the sine of the angle and the pull in lbs to figure the resultant forces applied to the saddle and the bridge plate.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Some would argue that the string break angle should be the same for each string as to have it balanced at each string. Some are also using wider saddles and ramping the backs of the wider saddle to allow for more of the strings energy to be transfered to the top by a wider bearing surface. Also more room for intonation. One also needs to take into account that factory guitars don't always make decisions from a tone point of view but from a production point of view. Or they would have different size bridges for different size guitars. He's an artical that may help some. Just be sure to click on the "Figure" while reading it.
http://esomogyi.com/principles.html

If you like this kind of information you will like the books.