crack repair question

Discussion in 'Hardware, Setup & Repair [BG]' started by madmachinist, Jan 31, 2014.


  1. madmachinist

    madmachinist

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    ok , it's not a bass (1930's Martin -A flatback mandolin) , but it has a 3" hairline crack in the lower -mid left of the rosewood
    back . i don't want it to spread and become a split .

    it is a roundhole instrument , so i could possibly glue in a patch
    from the rear if i had to access it .

    my thoughts are :

    a) vee it out , superglue the crack and fill it...

    b) keyhole it on the ends with a small hole
    fill the crack and leave it alone

    c) patch on the inside and fill the gap on the outside with
    shellac

    some stock photos of (not my) instrument:

    http://www.denverfolklore.com/instrument_photos/Martin_A_Model_mandolin_photos.htm

    any suggestions would be appreciated.
     
  2. RSBBass

    RSBBass

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    First, here is a great resource where you are likely to find more info than a forum that mostly covers solid body electric instruments:

    http://www.mandolincafe.com/forum/forum.php

    Second a 1930's Martin is way too good of an instrument to be learning repairs on.

    Third evaluating a crack and the best way to repair it involves looking at it, preferably in person but good pictures are a huge help.

    Finally, hairline cracks are not unusual in the winter. It may heal itself if you get a room humidifier.
     
  3. 96tbird

    96tbird This Indian movie is really boring man.

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    Professional help is indicated.
     
  4. pfox14

    pfox14

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    The proper way to fix a crack like that is a glued in thin piece of rosewood (usually called a cleat), which can be done through the sound hole. I would take it to a good luthier to have the work done.
     
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  6. Luthier Atlanta

    Luthier Atlanta

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    Don't even need to V it out. Get yourself two bar clamps with soft tips and glue it and clamp it quickly. I use Super-thin super glue for these type of repairs.
     
  7. walterw

    walterw Supportive Fender Gold Supporting Member

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    +1 to no guessing or OTJ training here, you get one shot to get it right.

    +1 also to talkbass being an odd place to even ask about it! the fact that you asked it here frankly makes me even more inclined to second the "let a pro do it" advice.
     
  8. SirMjac28

    SirMjac28 Patiently Waiting For The Next British Invasion Gold Supporting Member

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    +10000
     
  9. P Town

    P Town Guest

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    "+1 also to talkbass being an odd place to even ask about it! the fact that you asked it here frankly makes me even more inclined to second the "let a pro do it" advice."

    Hey, don't be so quick to say this is the wrong place.

    There are a LOT of VERY SMART people on this forum.

    I have been thinking of asking for medical, investment, and legal advice here.
     
  10. Pilgrim

    Pilgrim Supporting Member

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    Please keep in mind that any such advice is worth exactly what it cost you. ;)

    What stands out to me is that this is indeed a repair you only get one shot at. I would either do one helluva lot more homework than posting on an Internet forum, or take it to a pro.
     
  11. P Town

    P Town Guest

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    I've paid big bucks to professionals for advice in all three areas that turned out to be worthless.
     

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