Mandolin warped soundhole repair question

[Mark G]

Hello all,

A client asked if I could fix a little old mandolin he found in an antique store. It's an old italian bowl back made in Sicily. It came with missing pearl inlays, a loose top brace and dry, cracked fingerboard with a significant warp in the sound hole. I happily took it as the brace repair and inlay etc is well within my skill. I told the owner that the soundhole might present a problem and that I was not sure I could correct it. I was right. After the brace was repaired it came down a bit. I heated and clamped the area which also helped a bit but strung up the instrument cant be fretted without making contact on the E and A set of strings. If there is anything else I can do without pulling the top off- I know the owner won't want that and time wise is a major commitment, i would appreciate any thoughts.

[peter.coombe]

Bent neck and/or warp around sound hole is a very common problem in these sorts of mandolins. It is usually caused by using strings that are far too heavy, these mandolins were not built for todays modern heavy strings. Make sure you use ultra light strings so you don't add to the problem. GHS are about the only string supplier that offer a string set that is suitable for bowlback mandolins. The gauges are 09-13-20-32. If you are using heavier strings, get them off now.

Unfortunately I can't help you much on what to do about the warp around the soundhole since I have never fixed this problem. When I get these mandolins that have sunk or bent, I sent the owners away because the cost of repair is likely to be far more than what the instrument is worth.

[Mark G]

Thankyou for the input Peter, I have put 10-36 gauge D'Addario strings on her but I'll change that ASAP. The gentleman who owns the instrument has seen it and is very pleased with the condition I have put her back in despite the warp and will likely just leave it as is. Many thanks.

[Hard Road]

Have you tried introducing steam into the sound hole and slowly pulling the top flat as it relaxes? Cheers Paul

[lauburu]

introducing steam into the sound hole

Careful, I tried this method many years ago on a warped mandolin soundhole. Worked great but the steam also worked on the animal glue holding the braces. Some weeks later, in the middle of a concert, a loud bang was heard as a brace gave way and my mandolin imploded. Awkward.
Miguel