Repairing a Collapsed Acoustic Guitar

New Orleans humidity is rough on things. It’s relentless grip on the Gulf South is unforgiving of most man-made objects not designed for swamp life: houses, vehicles, books, anything electrical, and definitely guitars. The combined string tension at standard tuning is about 160 pounds of constant pressure on the soundboard – which means acoustic guitars are inevitably on the losing side of a very slow game of tug-o-war. Now, add New Orleans’ heat and moisture, which can start softening the aliphatic glue or hide glue with which many high-end instruments are assembled. Once the glue starts softening, the guitar is on a rapid downward spiral and will eventually succumb to the pressure and begin caving in on itself, and an acoustic guitar can collapse. That’s exactly what happened to this unfortunate Martin D-45 that landed on my bench. Below is a photo journal of my process of repairing this collapsed acoustic guitar.

This Martin D-45’s heel block shifted forward as the glue joint failed, collapsing the sound hole and rosette.
Here I’m using a heating pad to loosen the fretboard tongue from the sound board.
A modified soldering iron works perfectly as a heating probe to loosen the dovetail joint.
Some of the soundboard came out with the neck as it was detached from the heel and internal bracing.
Guitar repair isn’t always a one-man job. Here’s Benjamin helping me get this neck heel realigned.
I used a roll of tape to push the soundhole back into round. Hi-tech stuff!
This is exactly why I never throw away inlay material scraps.
I waited until this stage to reattach the broken sound board piece to avoid risking getting glue into the rosette channels before I fixed them.
I used a blend of three different nail polishes to paint. Whatever it takes!
Fresh coat of clear lacquer to seal the deal.
Time to set the neck.
And a Plek fret level, just for good measure.
Good as new!

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