Nitrocellulose Odor!

Discussion in 'Luthier's Corner' started by Nightman, May 28, 2018.

  1. Nightman

    Nightman If it ain't low, it's got to go! Supporting Member

    Jun 3, 2013
    Atlanta, GA
    So, how long will it take for the smell/odor from the nitrocellulose coating to dissipate?
     
  2. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    A few days to a few weeks, depending on temperature, humidity, ventilation and your personal sensitivity.
     
    Nightman likes this.
  3. Nightman

    Nightman If it ain't low, it's got to go! Supporting Member

    Jun 3, 2013
    Atlanta, GA
    Hey Bruce.. I must be really sensitive to this smell cause it seams to be lingering a lot longer than I would have expected.
     
  4. Nightman

    Nightman If it ain't low, it's got to go! Supporting Member

    Jun 3, 2013
    Atlanta, GA
    Are there real advantages to using nitro over poly?
     
  5. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    The fumes from nitro lacquer and lacquer thinner are nasty and dangerous, and flammable. I'm quite sensitive to it; it can give me immediate headaches. I only use nitro a very small amount here in my shop, only when nothing else will do. And I use it carefully with a full respirator and good ventilation.
     
  6. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    The big advantage to nitro lacquer is for final clear top coats. It's easy to spray nitro so that it flows out like glass. It levels by itself very well in thin coats. And it's completely clear over dark colors. And it's easy to level sand and buff up to a high gloss. It's the easiest way to a "piano finish"; high gloss over deep black.

    That's where I use it; the last top clear coats over dark color instruments. I want it only for the look, that deep gloss. I hate it otherwise.

    Downsides are: Fumes, flammability, expensive, many thin coats needed, cracks easily from temp changes, not very tough, scratches easily.
     
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  7. Nightman

    Nightman If it ain't low, it's got to go! Supporting Member

    Jun 3, 2013
    Atlanta, GA
    Thanks, Bruce!!
     
  8. Hopkins

    Hopkins Supporting Member Commercial User

    Nov 17, 2010
    Houston Tx
    Owner/Builder @Hopkins Guitars
    In my opinion there are absolutely zero advantages to nitro over modern urethane finishes (automotive finishes). Nitro is soft, will always feel sticky in a hot environment, it cracks from temperature shock, it turns yellow, and it just doesn't hold up as well.

    The only reason people still want it, is the same reason they want cloth insulated wire, grey pickup bobbins, and paper in oil caps. Because it was available back when Leo was making instruments and for some reason they think nostalgia makes it better. Despite the fact that all of these things are basically obsolete
     
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  9. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    I agree completely. The only reason I use nitro lacquer for the last clear top coats instead of the modern automotive urethanes is the modern (oil-base) urethanes get into another category of fire and safety regulations. Around here, using them means a licensed spray booth, inspections, etc. My lease specifically prohibits them in our building. We can get away with small amounts of nitro lacquer, with some caution and discretion. Almost all of our painting here is water-base paints only.
     
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  10. Hopkins

    Hopkins Supporting Member Commercial User

    Nov 17, 2010
    Houston Tx
    Owner/Builder @Hopkins Guitars
    Water based automotive paints have come a long way, especially the clears. I haven't switched because my guns are not stainless lined, there is a learning curve to spraying water based and it's crazy expensive (around here) compared to 2k clears and solvent based base coats.

    I'm surprised that the 2k urethanes are more strictly regulated than nitro finishes in California. Both outgas about the same amount
     
  11. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    No, I didn't mean to imply that. If we were using nitro lacquer all the time, we'd have to have the same booths and safety gear and inspections, etc., as with 2k urethanes. I meant that we cheat a bit with nitro lacquer, keeping only a small quantity at a time and mostly spraying outdoors.
     
  12. Arie X

    Arie X

    Oct 19, 2015
    my wife had a new custom luthier made acoustic with lacquer on it that smelled like a meth lab for about three month until we got rid of it. the fumes were eye burning. the stink soaked into the case as well and was a still a bit tacky when we consigned it out to a local dealer.