Regal bowl back repair

[Levi S]

This is my first post at the cafe, so I’ll tell you a little about myself.
I’m 60, I’ve spent the last 8 years learning the violin, and have just recently got serious about the mandolin. In my real life I’m a Tool and die maker, and I’ll attempt just about anything do it yourself.
Now about the mandolin I’m working on, it’s a Regal bowl back and I have no idea how old it is, I got it cheap from local Craigslist. The neck was close to falling off and the fretboard was quit bent. The “bowl” didn’t look bad. Well I got the neck off, cleaned up, glued back on, and the fretboard back in place. Because the top is caved in quite a bit I’ve had to make a shorter bridge to compensate. I strung it up and was surprised at how good it sounded. The A and E strings really sing, but the D string just sounded too dead.
Not terrible when played as an open string, but more of a plunk when played fretted.
I searched all of the forum posts regarding this issue, and none of the fixes seemed to help much. I was about to start trying different string combinations, and then I thought about what I knew about violins, got a mirror, and light and started inspecting the tone bars under the top. Low and behold the second one back toward the bridge was cracked clean through on a diagonal. They did a lousy job of grain orientation when selecting the piece at the factory.
Anyway with the aid of a mirror I carefully dripped some glue down into the crack off the end of a piece of bent wire. It’s now clamped up and hopefully I’ll have some good results tomorrow.
I’ll be happy to take any input anyone has, and I’m wondering how you would take the top off of one of this kind of mandolin. I know how to disassemble a violin, but it looks like you would just about destroy the top of this thing trying to take it off. In case it comes to it are there any tricks I should know about?
Have a great night, and thanks for the forum.
Levi

[Jim Garber]

Check out Dave Hynds of France page here. He has been taking on some close to hopeless cases and figured out how to fix them. John Maddocks in the UK has also done lots of worm on bowlbacks. Here in the US there are few luthiers who want to bother fixing this type of mandolin.

[Levi S]

That’s good to know.
I like to collect things, so collecting things that are in general not of any great value fits my budget.
My crack repair seems to have done the trick, and the D string tone is now at least acceptable.
Which is to say that it’s not noticeably dull as compared to the A string.