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PostPosted: Thu Oct 30, 2014 1:45 pm 
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Brazilian Rosewood
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Not mine, and not a customer's guitar... I noticed someone selling it cheaply and said it needed "some repair".

What could possibly cause this kind of damage? A Gremlin with a hammer destroying the guitar from the inside?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

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PostPosted: Thu Oct 30, 2014 2:12 pm 
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Attachment:
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Always make sure you use fresh glue.

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PostPosted: Thu Oct 30, 2014 2:29 pm 
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Probably a void or separation in the plywood.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.


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PostPosted: Thu Oct 30, 2014 2:34 pm 
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See how high that saddle is....a lot of extra torque on the bridge. Also when the finish was scored to remove for bridge placement my guess is who ever did the job at the factory cut the fibres of the top through and that caused the damage.

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PostPosted: Thu Oct 30, 2014 3:16 pm 
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Brazilian Rosewood
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Rod True wrote:
See how high that saddle is....a lot of extra torque on the bridge. Also when the finish was scored to remove for bridge placement my guess is who ever did the job at the factory cut the fibres of the top through and that caused the damage.

Yup and if you look at the high rez pic it shows clearly that there is probably 5mm or more finish around the border that is untouched. So there wasn't much holding it on there.


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PostPosted: Thu Oct 30, 2014 3:24 pm 
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I see this a lot in cheap guitars, often with the bridge loose. When I reglue them, the removal was easy since there wasn't much holding the bridge down to begin with. It almost looks like the bridge was simply placed onto the wet finish or something, not sure the kind of glue used, it's clear and looks to be the same material as the finish. There are often at least 1/4" of finish under the bridge so the bond is never good. I would score around the finish, remove them, and reglue them and it has not been a problem since.

My guess is, the bridge came off, the owner left it strung up and played it for however long it worked, and the top finally gave out as the bridge plate is taking more stress than it could possibly handle. It would take some serious force to damage plywood this badly though... they are normally very strong and the only time I was able to damage them intentionally was hitting it very hard with a hammer.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com


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PostPosted: Thu Oct 30, 2014 4:36 pm 
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I also suspect a gremlin. Never feed them past midnight.

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PostPosted: Thu Oct 30, 2014 5:45 pm 
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Tai Fu wrote:
... not sure the kind of glue used...

Quite often CA gel.

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PostPosted: Thu Oct 30, 2014 10:40 pm 
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No wonder they came off so easily... CA has NO shear strength.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com


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PostPosted: Fri Oct 31, 2014 8:15 am 
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Yeh, but it doesn't look like a glue failure.

In the factories, the finish is usually thick polyester, which is routed off at the bridge location. This one fits that profile as you can see the radius of the cutter at the bridge corners. Quite possible that the routing was too deep (or the finish thinner than the 0.5mm expected). There is no evidence of a bridge plate, as far as I can see, or if it has lifted with the bridge (i.e. no overlap) it was too small. So it looks like a peel failure due to lack of a proper bridge plate, exacerbated by routing too deep into low quality ply.

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PostPosted: Fri Oct 31, 2014 9:26 am 
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Alex thanks for posting that picture of the lepages glue it brought back fond memories of elementary school in MTL in the 50/s.It/s funny you posted it, as I was telling someone yesterday , and describing the bottle I used to glue craft projects /paper together in school back in the day cheers ernie


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PostPosted: Fri Oct 31, 2014 9:53 am 
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Your welcomed Ernie. I thought that I would leave it to the more experienced to figure out the damage, but I often think of the Lepages and Elmer's school glue when I reach for a bottle of wood glue. I used the same stuff in the '60's, along with the fat red pencils, and later, when we graduated to ink, the old fountain pens. Little things can sure bring back some great memories!

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PostPosted: Fri Oct 31, 2014 10:43 am 
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True that alex , we have elmers, and everything else , but I haven/t seen any lepages since we left BC in 1990, regards ernie


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PostPosted: Fri Oct 31, 2014 6:30 pm 
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I'd say most of that glue joint held. It ripped a huge hole in the top!

You can really see the finish ridge. Definitely not a good way to go.


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PostPosted: Sat Nov 01, 2014 1:21 pm 
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Sure case of bridge bore, often a tropical problem.

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PostPosted: Sat Nov 01, 2014 9:58 pm 
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I'm with the others here, too high a saddle and probably a ply top without much stability.

Regarding CA, I could be wrong but I recall Rick Turner saying he has been gluing bridges down with CA for years with no failures.

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PostPosted: Sat Nov 01, 2014 10:19 pm 
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It's a standard failure.

When the bridge was glued to the plywood top, the finish was scored, and removed to accept the glue. All too commonly, the scoring was heavy-handed and cut right through the upper veneer at the back edge of the bridge. Then the bridge pulls the upper veneer loose, peeling it away from the middle, cross-grain layer.

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