Repair of a Fractured Soundboard

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Here is a photo of Dr. Joe Vitale’s Elko model guitar we made for him
– beautiful figured bubinga back and sides with a wonderful redwood top. We were happy that Dr. Joe bought this instrument because we thought its looks and sound were sweet.


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However, the next time I saw the guitar after delivering it to Dr Joe, the top looked like this. Let me preface this by saying that Dr. Joe is a man of integrity. If you have read any of his books, listened to his recordings, or ever met him, you know this. Dr. Joe went on vacation, left this guitar inside a glass case in an air conditioned house. He came back to find the guitar hanging where he left it, but in this condition. I believe there is more to this story than either Dr. Joe or I will ever know, but it just doesn’t matter. This was such a great guitar, I had to repair it.
It appears somehow suddenly the string tension was increased, tearing the fibers in the redwood top apart and shearing the bubinga bridge plate in half through the holes for the bridge pins. Note that the hide glue held so well that the bridge did not separate from the top, but rather the top was ripped apart. I started the repair by cleaning all of the redwood from the bottom of the bridge.

elko-7The first thing I did was glue the sides of the crack together with hot hide glue. I used flat cauls to get the top back as flat as possible. It came together well.
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elko-10I cut a redwood plate that would fit between the x braces inside, and glued it in place with hot hide glue.

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elko-12Next I glued a patch inside to cover the remaining hole on the outside of the x brace. While that was drying, I prepared patches to reinforce the cracks I had glued up previously. The second photo shows the patches in place inside the guitar.elko-13

Next a patch was fitted and glued in place to fill the remaing defect in the top. I was now ready to glue the bridge back in place. Normally I would only use hide glue to attach a bridge. However, there are defects in the top in the footprint of the bridge. Since I needed to fill these gaps, and this top could not stand for this bridge to be removed again, I mixed up epoxy. I thickened it with glass beads, and colored it brown with some dye.elko-5

I laid down masking tape over the bridge foot print, located the bridge, locked it in place with plastic bridge pins, cut around the bridge just deep enough to go through the tape, but not into the top, with a very sharp #11 blade. Then I removed the tape over the bridge foot print, and I was ready to glue on the bridge using the epoxy.

I clamped the bridge in place after applying epoxy to the bridge and top. I cleaned up the squeeze out with a q tip and alcohol. Then I removed the tape, and was left with a very clean glue up of the bridge.

Here is an inside view of the bridge glue up showing the friendly plastic caul which was molded to fit the underside of the top, patches, and braces perfectly.
A bubinga bridge plate was glued to the underside of the  redwood patch inside the guitar.
The bridge was taped off and lacquer was sprayed onto the top.