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What's the worst that could happen if I varnish too soon?

BuckyBucky -
edited August 11 in General Discussion
I recently completed a painting that has just been accepted in to a group show that opens next month. The load-in date for the exhibit will be just slightly more than two months after I completed the painting. I would REALLY like to have it varnished before the exhibition as it's vibrance is definitely fading as it dries. I know the minimum drying time is generally thought to be three months but if I were to varnish it just before the exhibition, which would be the two month mark, what would be the worst that could happen if it's not fully cured even though It's definitely dry to the touch? It was painted with Geneva Paints. 


  • Bucky

    Entering an exhibition or even the off chance it could happen I would be using a non slow dry medium.
    If really pushed I would be using Liquin.

    Ideal drying time is six months. Premature varnishing may result in the varnish solvents softening and binding with the paint. In combination with temperature and humidity excursions, wrinkling or cracking is a risk. Future varnish removal and renewal may be impossible. Thick or impasto passages will remain mobile under a varnish for many years, increasing the risk of damage.

    Maximise drying with heat in a dust free but open to air flow enclosure

    Heck, I have heard of paintings being varnished early with no problem.

    GamVar can be applied when the paint is touch dry.

    Retouch varnish can be used and the painting will continue to dry as it does with GamVar.

    Good luck with that and hope the show goes well for you.


  • PaulBPaulB mod
    Congratulations on the show! This is a common problem.

    The time it takes for paint to dry / polymerize / oxidize / cure is dependent on many things, including:

    - ambient temperature
    - substrate / ground absorbency
    - thickness of paint
    - amount of medium in paint
    - type of medium in paint
    - type of paint
    - thickness of paint
    - presence of layers in the paint

    and more. Given all these factors, it makes no sense at all for there to be a single recommendation on how long to wait for it to dry. If you paint thinly with medium in one layer, your painting can be dry in days.  If you have great thick impasto globs, it can take a year, perhaps more, I don't know. You have to use your judgement.

    If you use a retouch varnish, which is just varnish with lots of solvent, it is somewhat porous, allowing oxygen through. This means the paint can continue to dry despite there being a single coat of retouch varnish.  Gamvar is one such example, and the Gamblin recommendation is to wait until it's touch-dry.  This does not mean when you can handle the painting, it means when you can't push your fingernail into the thicker parts of the paint.

    For thicker varnish, such as Damar, you would need to wait longer, because it is not porous, and applying that varnish stops the drying process.

    What is the downside to varnishing too early?  The paint may never fully dry, and the varnish cannot be successfully removed without also removing some of the paint.


    For something like this with a deadline, I tend to wait until the last few days where I have the painting unframed, and apply a single, oh-so-thin coat of Gamvar gloss. It helps to be familiar with Gamvar, and the ways in which it can misbehave.

    If I have more time, or I think the painting is really dry, I use Grumbacher Damar in a spray can, for the sheer convenience and good results.
  • Thanks so much @dencal and @PaulB, very helpful info, indeed! I'm thinking I'll go with the Gamvar option for this situation. 
  • PaulBPaulB mod
    The conclusion in the clip is bogus. Is one layer of thin paint on canvas typical for a painting? Was that varnish the same thickness each month, because we know it's viscosity changes with temperature, so was that controlled? Florida cools down in winter, which months were those? The first? Isn't it thick paint where we have the most trouble deciding whether it's dry? Does anyone ever experience *consistent* sunken areas? Is it therefore a good idea to make a recommendation based on one trial, using one thin layer, drying in Florida heat?

    This is just for fun. Like me having painted DiBond out in my yard to see what happens. This shouldn't be used as a basis for recommendations.
  • Gosh those guys are smart! @dencal and @PaulB and Bucky too for asking before taking a chance on  Murphy's Law.
  • Seems like there are so many potential problems that can happen from varnishing too early. It's not really something to be taken lightly if ibe really cares about how their painting looks and survives in the future.

    There was a good article recently published on the natural pigments site on the topic of varnishing. That site has some of the best info on these kinds of topics. Nicely organized and digestable as well.
  • Varnish may contain turpentine or other thinners. If your painting is not totally surface dry it might negatively inflence the paint layers. Push fingernail into paint surface. If you see that fingernail makes a mark then paint is not dry enough.
  • I will tell you how you can do a retouch varnish from scrap, 1/4 part of Dammar varnish, 1 part of linseed oil and 1 part of turpentine. I did it with my last painting and it doesn't show any problem. The recipe is from a teacher from the Russian Academy in Saint Petersburg.
  • @Bobitaly I wonder if that teacher knows that linseed oil permanently yellows and can be impossible to remove in the future. 

    The best varnishes are ones that dont yellow and are easily removable (which they will be if the painting has had long enough to dry). Using linseed oil as a varnish or to oil out an entire painting is a bad idea. It should only be used to oil out areas that you are going to add more paint to, and then the smallest amount possible should only be applied, otherwise you might end up with something looking like this

  • wow @CJD what is happening in this photo?? I think the point is to add a layer so thin just to revive the sunken areas. Dammar yellows too, all natural resins yellows with time... Easiest and safer solution is of course to use a synthetic varnish that dosent yellow, the market is full. 
  • Here's a post George O'Hanlon recently shared on his Facebook "Painting Best Practices" group.

    Do I really need to wait six months?

    The Big Sleep before Varnishing
    The age-old advice to wait at least six months before varnishing oil paintings is a good practice, but one that is resisted by many artists. And it is understandable why because when a painting is completed it often needs to be delivered immediately for exhibit or into the customer's hands.

    So, artists often tout the recommendation to wait until the painting is "touch dry". For some this may be a sufficient amount of time. This recommendation, however, assumes that all paintings are created under the same conditions. Of course, we know this is never the case, since one painter paints on absorbent substrates, another on non-absorbent surfaces, another will use lead white others will use slower-drying titanium white, many paint with impastos and others with thin applications of paint.
    A few manufacturers claim that their varnish can be applied much earlier, such as when the painting is "touch dry", so many artists grab this idea and run with it thinking the moment the paint surface feels dry they have a green light to varnish. However, even these manufacturers are a little more cautious by recommending to test the surface of the painting for sufficient dry time such as with a "fingernail test".

    Somehow many artists believe there is something special inherent in these varnishes. One blogger writes:
    Gamvar allows the painting to continue to breathe so the paint underneath can still continue to dry. It doesn’t stop the drying process.

    In reality, all varnishes are permeable so oxygen will diffuse into and through them, allowing the polymerization of oil paint underneath. All varnishes, of course, slow the ingress of oxygen into the paint film, thereby delaying the drying process.
    Waiting at least six months is still the best practice that can apply to a wide range of painters. In lieu of that, an artist may use (with due caution) the test described below as a method to determine when the painting is ready to be varnished, if she cannot wait the prescribed six months.

    The "fingernail test" may be what some manufacturers had in mind for the test method for "Dry Hard Time" described in ASTM D1640:
    With the end of the thumb resting on the test film and the forefinger supporting the test panel, exert a maximum downward pressure (without twisting) of the thumb on the film. Lightly polish the contacted area with a soft cloth. The film is considered dry-hard when any mark left by the thumb is completely removed by the polishing operation. Remove any coating from the thumb immediately. The use of a glove, finger cots or the presence of freshly-applied cosmetic products/hand creams may interfere with the test results.

    Variations of this test may be used but will also give different results. A problem with using a hard and sharp object such as a fingernail (in contrast to a flat thumb) is that it can give false results depending upon the amount of pressure exerted into the paint film.

    Whereas the test described above may work in your case, always keep in mind that some interpretation of the results is involved, often leading to different conclusions. The safest and best practice is to wait the prescribed amount of time—at least six months. But if you cannot do so, then use the test method ASTM D1640, and good luck.

    For more information on varnishing, please consult this article:

    @bobitaly it's [email protected] it's just an example of what can happen if too much medium is used in paint or if linseed oil used to oil out or varnish yellows over time. The difference between using varnish that yellows and linseed oil is that at least the varnish will be easily removable (assuming it wasn't applied too early). This is especially relevant when you consider that many artists use linseed oil to oil out after the painting is only touch dry which increases the chances that it will be impossible to safely remove in the future.
  • This is crazy. Just use spray on retouch varnish. 
  • I use Gamvar when the thickest paint passes the thumbnail test. I can’t predict the future performance but all that I read says it’s ok. I use the very minimum amount of varnish possible and brush it in actively with a china brush. 
  • @tassieguy
    Saving this quote forever!:
    Given all the things that could go horribly wrong, I'm constantly amazed at how people keep getting up in the morning.
  • I varnish paintings when the colors totally look dry and dead (of thirst perhaps  :p ). That's the safe limit ...paint can't react to practically anything except fire! 
  • edited August 27
    When I can paint a masterpeice (and know that I can easily repaint it after it falls wet, face down, on the carpet) then I'll start worrying about varnish.   :)
  • kaustavM said:
    I varnish paintings when the colors totally look dry and dead (of thirst perhaps  :p ). That's the safe limit ...paint can't react to practically anything except fire! 
    I use the same criterion.  Funny the way that you explain it.
  • Summer said:
    kaustavM said:
    I varnish paintings when the colors totally look dry and dead (of thirst perhaps  :p ). That's the safe limit ...paint can't react to practically anything except fire! 
    I use the same criterion.  Funny the way that you explain it.
     :)  :p
  • Although Geneva paints are slow drying I think the actual paint film thickness (because it's so fluid) is less than that used by people who use more impasto or palette knife work. So it might not take as long as those paintings to be dry enough to fully varnish.
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