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  #16  
Old 06-20-2019, 06:51 PM
snow creek snow creek is offline
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Have you looked inside the instrument to see if there is damage that perhaps caused said crack in the bridge?
And why CA glue and not Epoxy? (for the experts)
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  #17  
Old 06-21-2019, 01:26 AM
nikpearson nikpearson is offline
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Default Good point.

Quote:
Originally Posted by snow creek View Post
Have you looked inside the instrument to see if there is damage that perhaps caused said crack in the bridge?
And why CA glue and not Epoxy? (for the experts)
The photo suggests that the crack runs from the centre inner edge of outer bridge pin holes in a straight line. My guess would be that there was a weak point in the ebony and the bridge pin holes or maybe even the pins themselves have resulted in the crack. The crack appears to stop at the outer bridge pin holes. Definitely worth checking inside the guitar to make sure the issue doesnít extend to the bridge plate although Iíd be quite surprised if it does.

Iíd be inclined to use superglue rather than epoxy because it flows better. Thereís a good chance medium viscosity superglue will penetrate the full depth of the crack and thin viscosity certainly will. Fine ebony dust can be created by sanding the bridge with 400 grit or similar. You could then wick some thin super glue into the crack and carrying on with light sanding until the crack disappears. Thereís little to lose by trying this method and the crack will be invisible and I suspect wonít reappear. A replacement bridge is more expensive and would be non-original.

Ebony is very prone to shrinking and cracking even without the help of bridge pin holes and pins. If every crack results in the need for a replacement part...
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  #18  
Old 06-21-2019, 06:11 AM
pcturner pcturner is offline
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Default No internal damage; luthier recommendation needed.

I did have my local luthier look inside the instrument, and we could not see any damage internally. What I need is a recommendation for a luthier somewhere in the vicinity of Florida who is willing and able to do the superglue job! The luthier nearby was not willing to do that. Nigel Forster recommended a guy in Ohio, Greg Maxwell of Dogwood Guitars.
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  #19  
Old 06-21-2019, 08:51 AM
runamuck runamuck is offline
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Quote:
Originally Posted by nikpearson View Post
Using superglue and sanding will cover quite sizeable cracks in ebony and the repair will be invisible. The glue doesnít dry immediately and the mixture of ebony dust and glue will easily fill a crack of this size. Iíve used this technique to repair cracks in ebony fingerboards, gaps around inlay, and on unbound fingerboards where the fret slots were deeper than the tang. All of these fixes are invisible.

If you mask of the bridge carefully there is virtually no risk (famous last words) of getting superglue anywhere other then the bridge.
I agree with all this, that superglue will fill the crack and if done properly can be invisible. But superglue it not good structurally in filling a large gap.
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  #20  
Old 06-21-2019, 07:52 PM
snow creek snow creek is offline
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Thanks for the info. I love how experienced people on here are willing to give advice.
As to the CA glue- what type should be used?
My guitar has bridge cracking issues as well...
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  #21  
Old 06-21-2019, 08:19 PM
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Bruce Sexauer Bruce Sexauer is offline
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I see a lot of agreement that CA is a cosmetic fix. If it is cosmetic . . . why bother? That's why I favor bridge replacement.

To clarify: I have never succeeded at repairing a cracked bridge. They have always failed again. The only failure I've seen in my work is through the saddle slot, however.
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  #22  
Old 06-21-2019, 08:47 PM
nikpearson nikpearson is offline
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Default Cosmetic? Sort of...

A superglue and ebony slurry repair will take a few minutes and cost next to nothing. A replacement bridge is a bigger job and therefore more costly. I see no reason not to try the superglue fix and if the crack reappears consider a new bridge.
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  #23  
Old 06-23-2019, 08:43 AM
phavriluk phavriluk is offline
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Default all true

CA, aka 'superglue' is indeed magical stuff. But it has no surface tension, wicks everywhere, and goes into places where it isn't needed, whether or not the person applying the stuff intended it to get there. I am hyperconservative when using the stuff, and putting it on a cracked bridge whose crack goes down to the unfinished wood on the top underneath the bridge, and the crack for sure goes through the height of the bridge top to bottom, so the glue is able to get to the soundboard...unknown and unpredictable results are on offer. I have no idea whether anything particularly bad results, but CA will make its way to the bridge/soundboard intersection, and I have no idea how much that will matter if the bridge comes to need replacing.

Just a thought from someone who's never dealt with a cracked bridge.
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  #24  
Old 06-23-2019, 03:47 PM
John Arnold John Arnold is offline
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Quote:
I see no reason not to try the superglue fix and if the crack reappears consider a new bridge.
Even in those cases, a second try at the same repair is not unreasonable, as long as the progression is not extreme. CA is unlike conventional wood glue, in that it will still adhere when the crack is already contaminated with CA in the past. I have done that a few times, and to my knowledge, it has never recurred.
Quote:
I have no idea how much that will matter if the bridge comes to need replacing.
As a veteran repairman (35 year's worth) who has done hundreds of these (in addition to all levels of top reconstruction under the bridge), I have seen no evidence of seeping CA around the pin holes creating issues with the spruce down the road. The most critical area for gluing a bridge is along the bottom edge, since that is where most bridges come loose. Saturation of the spruce around the pin holes does not seem to be an issue.
Quote:
But superglue it not good structurally in filling a large gap.
When the crack between pins is wide enough, I will add a sliver of matching wood (ebony or rosewood, usually) to fill in the gap. I also insert a tapered punch in the pin holes and 'lever' it (in the direction of string pull) to open the crack while applying the CA. This assures good penetration.
I am often asked why this crack is so common. Ebony is a brittle wood, and drilling 6 holes in a line and applying 180 +/- pounds of force is a textbook way to separate it into two pieces.
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