Thanks Todd,

The bridge is located approx. 1/2 the 24.9" scale length from the 12th fret neck joint so I'm not sure how I'd alter that location. I have noticed that some parlor bridges will 'appear' lower on the lower bout but that must be a function of the overall body length below the bridge?

Does having the bridge land over the X-Brace an important factor?

...
EDIT: The more I think about it I think I was imagining those forces on the bridge trying to rotate the bridge forward and therefore having the brace under the FRONT corner of the bridge to stop that forward rotation instead of the back corner to help stop the forward lift. Any logic in that thinking?

On the UMGF forum there is a library of Martin guitar bracing photos done by putting a bright light in the guitars and shooting photos. The interesting part of this is the variation of where the bridges land on the X brace. Check it out
http://theunofficialmartinguitarforum.yuku.com/topic/847

Fred

Yes, the rotation also pushes down on the front edge but moving the bracing back helps support that better too.

I'm always reluctant to get too specific about bracing. There are too many variables. That said, I think your new drawing looks a little off to me. The upper legs of the X typically hit the sides farther above the waist. If it were me, I would close it back up a bit. Maybe something like this pic in the thread that Fred linked to. http://theunofficialmartinguitarforum.y ... NG-LIBRARY

On a guitar this small, none of the braces need to be wider than 1/4" or taller than about 15/32" at the X. Also think a bridge plate brace might be overkill for a guitar that will already have significant along-grain stiffness courtesy of the fan braces. Always an option to do what JJ does and make one up before closing the box, then adding after if there is significant bridge roll.

I prefer the first drawing(the one at 90°). In the second, everything is shifted too far back, and I'm concerned with perhaps not having enough support forward of the waist, where it's nicely balanced in the first drawing. If you made the bridge just a wee tad longer(maybe as little as 1/8" to 1/4" longer), you'd have full support across the X braces, too.

What I question are the fan braces. Why do you wish to use this system? It's heavier and more complex than necessary. On such a small body, we easily get away with just one rear tone bar, and if you want a symmetrical system, keep the transverse brace behind the bridge plate, and add one more about 2" below that one. Or do a second, smaller and shorter "X" brace in place of the tone bars....

You can also make the bridge plate narrower, but you need to be positive about the bridge placement if you do so.

But if you went ahead with drawing #1 as it sits today, methinks you'd have a fine little guitar. Just keep everything light and 'free'.

I like the first drawing better too. Just fan the X to 93 degrees or so and make your bridge longer. I've built a bunch of size 2's like that with about 6.7" bridges. They've held up well and people like them. It'll be interesting to see what the fan braces do to the sound.

What fan braces do on a classical guitar is help bring out the treble response which is often the weakness of nylon strings. That's something a small steel string guitar doesn't need. Quite the opposite. With a small steel string guitar you want to help bring out the bass. So I would avoid fan braces unless they are very small. I'm with Grumpy on this, one well-placed tone bar and you're good to go on a small guitar.

This has nothing to do with bracing, but if that line through the center of the saddle is your scale length line, the bridge needs to go back about 1/8".

I much prefer using fan braces behind the bridge to control the monopole/bass response rather than tone bars. Lots of ways to skin a cat and all that... I've had decent results with tone bars, and just awful results with a second X or a lateral brace below the X like a Larrivee, but 2 or 3 fans starting just below the bridge pin holes have always worked very well for me.

One downside to using fans is that over time they tend to telegraph through a light top. I wonder if that's part of why tone bars evolved to be what they are today.

One downside to using fans is that over time they tend to telegraph through a light top. I wonder if that's part of why tone bars evolved to be what they are today.

One downside to using fans is that over time they tend to telegraph through a light top. I wonder if that's part of why tone bars evolved to be what they are today.

That probably has more to do with the amount of clamping pressure and how it effects the cellular structure of the wood. One has to pay attention to clamping "just enough".