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Just curious, what angle are you guys getting on your x-braces. I've drew out the brace pattern on my top using the connect the dot method with the Martin D-28 blueprint. The x-brace angle on the guitar top is 83 deg/97 deg but the angle on the blueprint seems to be about 82 deg. I know that everything shoots off of the x-brace so if that angle isn't correct, it can screw up the placement of everything else. Any help will be appreciated.

PS - This is for a drednaught.

I use 85 deg on my D models 25.4" scale length and 90 deg on my 000's and OM's. you want to be sure that the brace supports the bridge. In other words you want the path of the brace to be under the edges of the bridge. Especially on larger body guitars. So if you had a longer scale you may need to adjust the angle to support the bridge.MichaelP38384.6513310185

I use 98 degrees between the X?s on my Dreadnoughts and OM?s, it seems identical to what Martin uses.

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I have a more open X than most. My angle is about 96 degrees.

96 would be more closed than 98, Mike.

I know it can be read either way, but when we say "more open" or Open the X more", we always mean it the same way.

Okay, so the angle created by the intersection of the x-braces should be 98/82. Do you think that it would make much difference if it was 97/83? Excuse my ignorance but this is my first guitar. Thanks

[QUOTE=Mario] 96 would be more closed than 98, Mike.

I know it can be read either way, but when we say "more open" or Open the X more", we always mean it the same way.[/QUOTE]

I was looking a several different sets of plans the other day. Their Xs were running from 90 - 94 degrees. That's why I said mine was more open. I missed the post above that stated that Martin's is 98.

By the way the 96 degree angle is the angle bisected by the center line of the top.

I am no journeyman luthier by any means yet. But when I layout a new scale and x-brace pattern I have three goals in mind. First I want the lower ends of the brace to be under the bridge by at least 3/8" from edge of bridge. This will allow the first tone bar to x-brace intersection to be under the bridge as well. I want the upper end of x-brace to meet the lower edge of the upper transverse brace at the intersection of the side and upper tranverse brace if possible or with in 1/4" anyway. Third I want the tangent distance from the edge of the sound hole perpendicular to the x- brace to be between 3/8" min to 1/2" max. I have based this off of min, max positions of the three basic sized guitars I have varrified locations from. Martin OM, Martin D and Gibson J. I figure if this worked for them it can't be too far off.

I vary it depending on the cross grain stiffness of the wood. I think there's probably a 'correct' angle for any given set of wood and outline, but, as yet, I don't know how to find it initially except to go with what 'feels' right. One could, of course, keep records for a while, say, using the same brace angle on woods with different stiffness ratios, and see which ones worked better. I use 'free' plate tuning to look at the way the bracing and top are working together, and, if I need to, can make changes before assmebling the guitar, but the initial angles are educated guesswork.