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  #1  
Old 07-05-2013, 10:18 AM
sutherland sutherland is offline
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Default signs of age..or is the bridge going to fly off and hit me in my face

Perhaps the lines have always been there...perhaps I never noticed (I highly doubt that). I opened my guitar case of my 08 D-28 a few days ago, and my heart sank...

Some hairline cracks stemming from the bridge, an odd hairline by the upper bout, and some bubbling near the bridge itself.

My other acoustic instruments, kept in lesser cases but within the same moderated humidity do not show these lines. Please note, they are also much newer instruments.

I tried to capture the lines...I had to use Photoshop to adjust the curves/contrast of the image so they would display (in case you are wondering why the color of the image is really off).

So cause for concern or signs of age?

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Old 07-05-2013, 10:27 AM
Glennwillow Glennwillow is offline
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Hi Sutherland,

I'm not a guitar technician, but those lines appear to be surface cracks, though I could be wrong. If you are concerned, and it seems that you are, perhaps taking it to a trusted technician for evaluation would be a good idea.

You could purchase a mirror http://www.stewmac.com/Shopping?actn...tool&x=44&y=11 that can be placed through the sound hole. With the use of a small flashlight, you could like at the underside of the top to see if the cracks go all the way through the wood. That would tell you how series the cracks are.

Do you live in a very dry climate? Summertime is usually not a time of low humidity unless you live in a semi-arid region. Is the relative humidity well below 40% where you live?

Best of luck on this. I hope it's not a serious problem for you.

- Glenn
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Old 07-05-2013, 10:36 AM
sutherland sutherland is offline
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Quote:
Originally Posted by Glennwillow View Post
Hi Sutherland,

I'm not a guitar technician, but those lines appear to be surface cracks, though I could be wrong. If you are concerned, and it seems that you are, perhaps taking it to a trusted technician for evaluation would be a good idea.

You could purchase a mirror http://www.stewmac.com/Shopping?actn...tool&x=44&y=11 that can be placed through the sound hole. With the use of a small flashlight, you could like at the underside of the top to see if the cracks go all the way through the wood. That would tell you how series the cracks are.

Do you live in a very dry climate? Summertime is usually not a time of low humidity unless you live in a semi-arid region. Is the relative humidity well below 40% where you live?

Best of luck on this. I hope it's not a serious problem for you.

- Glenn
Hi Glenn,

Nope, no dry climate for me (although the guitar was purchased when I lived in Las Vegas - but that was quite a few years back). The guitar-friendly climate (excluding winter months, of course) of San Francisco.
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Old 07-05-2013, 10:39 AM
BGS BGS is offline
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It's fine. If you want to have a luthier/tech look at it to ease your mind, that's never a bad idea. But long story short - it will be fine. What would concern me more is the bridge actually lifting and pulling away on the bottom (closest to endpin) edge.
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Old 07-05-2013, 10:41 AM
BGS BGS is offline
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Finish checking can be caused by long-term humidity issues, but it's more commonly caused by rapid temperature changes. Leaving it in the car all day during the Winter, then taking it out in a warm room without time to acclimate. The opposite can be bad, but for different reasons.
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Old 07-05-2013, 11:40 AM
DanPanther DanPanther is offline
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I think these are all to common occurrences of modern hurry up production. Not allowing wood, and finish and glues proper time to cure. The ooze by the bridge I would say, is glue that had not cured properly is being squeezed out from under the bridge.
Is the guitar in a much different environment from where it was manufactured ? The wood has finally acclimated, but the finish had already sized itself, so it had no room to expand, and cracked.
Dan
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Old 07-05-2013, 12:15 PM
Dreadful Dreadful is offline
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The line from the corner of the bridge appears to be a finish crack, which is limited to the finish only and not the underlying wood. These have been called "whisker cracks," there is a lengthy thread in the UMGF on the subject. One of my five Martin's have them (2009 D-28), on all four bridge corners. It may be caused by the routing and installation of the bridge process, see the UMGF thread for details.

edit - I did not know the UMGF thread was closed, click on the link from bobby b's post below.

Last edited by Dreadful; 07-05-2013 at 12:31 PM.
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Old 07-05-2013, 12:23 PM
bobby b bobby b is offline
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Very unfortunate.
The 'whisker cracks' in the finish by the bridge, seem to be happening to more than a few Martin guitars.

Yours look very similar to those in other threads such as....

http://www.acousticguitarforum.com/f...=284973&page=5
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Old 07-05-2013, 01:37 PM
BluesBelly BluesBelly is offline
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The cracks or marks in the field are not exactly parallel to the grain so they are surface or finish cracks or scratches. The bridge marks are not serious. Probably movement or shrinkage in the finish. When a bridge begins to let loose the moment of intertia will twist the bridge toward the tension source which is the string(s). The signs of a loosening bridge would then appear on the back side of the bridge or toward the tailpiece in the form of seperation of bridge and top.

Blues
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Old 07-05-2013, 03:30 PM
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sweiss sweiss is offline
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Looks like common garden variety finish cracks to me.

I think most acoustics will develop these cracks at some point in their lives. All of my older guitars have at least some, and two of them are literally covered in them.

In any case, they're harmless.
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Old 07-05-2013, 03:45 PM
DanPanther DanPanther is offline
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I think the phenomenon on older guitars is more related to the nitrocellulose, and not the same as the recent spider cracks.
JMHO
Dan
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Old 07-05-2013, 04:33 PM
Diamond Dave Diamond Dave is offline
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It's gonna make you cuss when that bridge flies off and hits you in the face.
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Old 07-05-2013, 05:24 PM
harmonics101 harmonics101 is offline
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Wow, some of you guys must have some 3-D interpolated glasses that you're wearing.

There is NO WAY I can tell, from that angle the photo was taken, that the bridge is lifting.

You guys are good !!

Harmonics
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