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Old 06-17-2019, 05:47 AM
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keith.rogers keith.rogers is offline
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Quote:
Originally Posted by B. Howard View Post
No! They are not made flat. They are made with a slight curvature from the factory. Approximately a 53 foot radius on the top of any Martin guitar.

If they were made flat the stress of the strings and their 180 lbs of pull would cause the top to break in short order. In engineering terms the curve of the top makes it pre-stressed so as to not further deform under the pressure.
53 feet? Down? I.e., in the opposite direction from the fingerboard radius?

I'm not disputing your number, but I am pretty sure you wouldn't see that radius on a piece of wood only a few inches long. The picture posted shows a much more obvious dip than a radius of that size.

Edit: I've been reading about the top/back radii over at UMGF and remembering all the stuff I forgot about this. Of course, the top is radiused during construction - the amount doesn't matter. And, it is done to counteract the force of the strings pulling the bridge forward and down. A properly made bridge would be radiused to match the top curvature at the factory. Clearly, they distort to a flat or even downward curve (without breaking) over time. The picture seems a bit much for a new guitar, but as a subsequent post says, if the action is correct with that much bridge and saddle it's likely Ok. It is certainly not built in, though.
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Last edited by keith.rogers; 06-17-2019 at 06:25 AM.
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