Repair Mandolin Top Lifting

[Rikk]

I have a friend who has an older mandolin that she wishes to use as a decorative piece. I have been tasked with repairing it for a wall hanging.

I am, if possible to reattach the top, set the bridge and put on a set of strings at low tension (to hold the bridge in place and make it look right).

The top has pulled up from about 1 inch from the lower neck joint and extends about 8 inches. (or about the placement of the bridge) The gap at the height of the bow is about 1/4 inch.

As the mandolin is now decorative only and will never be under full string tension. Is there a simple repair to reattach the top without further damage to the wood? I can include a pic if needed.

[James Sanford]

Pictures always help.

[sunburst]

Not enough info.
There was a Loar used as a decoration on a wall over a mantle that showed up in a thread here once before.
The mandolin is probably not a Loar, but it could have potential future value as a playable instrument, so any repair done should be done as though the mandolin is being put into service as a playable instrument. That way, perhaps a week or a few generations later, it can be put to use as a musical instrument without having to undo a "half###ed" repair.

[Rikk]

The Mandolin says "Regal" on the interior label. Image attached

[sunburst]

I have one of those. Mine needs the neck re-attached, and I'll probably hang it on the shop wall and perhaps give it to some youngster who needs a mando to learn on someday. It can be made into a good player, so treat it with due respect.

First, check to see how well glued the rest of the top is and check other glue joints too. It looks like that separation is probably from glue failure, and whatever made it fail (heat? moisture?) in the past could have affected other joints too. If all else is sound, come up with a way to get good alignment when the gap is clamped closed, and re-glue it by working glue into the gap with a thin tool like a palette knife or a cut-out piece from an aluminum pie pan or "TV dinner" (does anybody still call them that?) tray or whatever. Have all the clamps and padded cauls you need to have even clamping pressure for the length of the gap, do a couple of "dry runs" to get the procedure down, put the glue in the joint and clamp. Clean up glue squeeze-out with a slightly damp soft cloth and wait for the glue to cure before removing the clamps.

It would be best to use hot hide glue, but it wouldn't be a terrible sin to use Titebond (original) or other quality plastic glue. I would suggest not using "superglue", "Gorilla glue" or other heavily marketed product that would cause future repair people major grief.