Sandblasting Finish

Discussion in 'Trumpet Discussion' started by dsr0057, Dec 20, 2009.

  1. dsr0057

    dsr0057 Pianissimo User

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    Dec 20, 2009
    Denton, TX
    I don't know if this has already been addressed, I searched but didn't find anything pertinent.

    I am overhauling a 1920s Bach Mercury Model from the original New York factory. I found it at a garage sale and got it cheap. It was in a sad shape. After much TLC I have it mostly back together with all original parts used. I am considering getting a sand blasted finish on it to take out some major scratches and hide the two major patches i put in the cracked bell.

    I was wondering if anyone knew of the positives or negatives to sandblasting a horn let alone a horn that old (the SN is 468 >.<). I know a lot about repair, but not much about the effects of sandblasting.

    Thanks much. I hope to have it done by the new year and have some pics up in the eye candy section.
     
  2. Solar Bell

    Solar Bell Moderator Staff Member

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    You mean bead blasting.

    Sand blasting wil destroy your horn.
     
  3. dsr0057

    dsr0057 Pianissimo User

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    Dec 20, 2009
    Denton, TX
    Thank you! I wouldn't want to destroy this thing after bringing back from the edge.

    So any pros cons that you know of?
     
  4. tedh1951

    tedh1951 Utimate User

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    It all depends on the finish you need - the aircraft industry has used glass bead blasting for years (essentially the little reflective beads that are mixed with paint and used for road lines) these are quite safe and are regularly used to blast corrosion out of aluminium (damage is possible if you are too heavy handed). More recently manufacturers like Boeing have been using pelletized dry ice - it removes paint without doing much further damage, or little plastic beads as an alternative - Google the Boeing website and look for the refurbishment of the old -80 B707 prototype.

    Make no mistake - this is a mechanical blasting process designed to abrade, you will need to get someone who knows what they are doing - avoid the mates who say, "yep, I can do that for you - easilly". If you are in any doubt - DON'T - think what water-blasting is capable off, and there is no added abrasive. I would suggest an instrument repair tech would be a real good move.
     
  5. ComeBackKid

    ComeBackKid Fortissimo User

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    Yorba Linda, CA
    If you have made the effort to use all original parts in the restoration, you need to ask yourself if a bead-blasted finish is what you really want. I assume that you would the finished product to be as close to original as possible. I don't know what the original finish looked like but if the repairs are well done, it may be possible to go back to the original finish and still minimize the visual impact of the repairs. My experience is that a bead-blast satin finish or a scratched finish do not hide flaws - they enhance them and make them more obvious. If the original finish was polished, I think that would work better. There is something about the reflections caused by a polished surface that tend to make flaws less visible.
     
  6. Brekelefuw

    Brekelefuw Fortissimo User

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    A lot of people use baking soda or baby powder on instruments to give it the bead blasted finish. You shoot it out of an air gun and compressor.
     
  7. JohnL

    JohnL Pianissimo User

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    Jan 17, 2004
    NJ/NYC METRO

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