Center seams sometimes split open. For instruments that do not warrent taking the top off, they can usually be repaired from the outside.
Here is a rental cello from another shop where the back seam opened up. After the the seam had been clamped for two days, I added some "temporary" glue cleats through the ff hole using a long wire and a drop of glue. These temporary cleats hold the seam together without having to fit a real wood cleat. If the cello is ever taken apart in the future, these glue cleats can easily be removed and real wood cleats can be fitted. The easiest way to remove these "temporary" glue cleats is to take a damp piece of paper towell and let it sit only over the glue cleat. After about 15 minutes, they can be easily cut away using a gouge and scraper.
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