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Alexa Dawn
12-22-2018, 05:15 PM
Is it necessary to varnish an oil painting when you plan on selling it or can it be sold without being varnished?

What's the minimum time after the painting is dry to the touch, to be able to varnish it?

WFMartin
12-22-2018, 05:59 PM
Is it necessary to varnish an oil painting when you plan on selling it or can it be sold without being varnished?

While some painters on this forum feel that it is totally unnecessary to apply varnish to an oil painting, others [such as I] feel that it is almost imperative!

To be considered an appropriate varnish, it must exhibit the following characteristics: 1) . It should provide an even, reflective surface of the painting, either glossy, satin, or matte. Rather than showing dull, and glossy areas, such as is often the appearance with no varnish, a good varnish will even out the sheen, making it uniform throughout the surface.

2) . It should provide a degree of protection for the painted surface, receiving the stress of scratches, stains, and dirt, that will accumulate over the years.

3) . It must be easily removable, with the weakest of solvents, without harm to the surface of the oil painting. And, yes, ....a varnish quite often will need to be removed, for any number of legitimate reasons.

What's the minimum time after the painting is dry to the touch, to be able to varnish it?

The criterion for applying an appropriate varnish is not measured in "time", but in "dryness" of the painting to which it will be applied.

The old time frame of "curing" for the painting before applying varnish was 6 to 12 months. However, even when using those older varnishes, you could create a "retouch varnish" that could be applied much sooner than 6 months. A retouch varnish is no more complicated than diluting a full-strength, final varnish in equal portions with its recommended solvent.

The newer, synthetic resin varnishes, such as GamVar made by Gamblin, can be applied shortly after the painting has become dry to the touch, and even at its full strength.

Do I believe in varnishing an oil painting? I absolutely do, for the three reasons that I mentioned. I believe that varnishing an oil painting is an absolute necessity to the appearance, and longevity (durability) of the painting.:) . I believe that I owe the buyers of my paintings to have each one of them appropriately varnished. I would not sell an unvarnished painting.

contumacious
12-22-2018, 06:17 PM
I will 2nd all of what WFMartin posted.

The only thing I would add is that you should indicate on the back of the painting or with the included certificate if any, or preferably both, the brand and type of removable varnish you used so the future owner will know how to remove it properly and also what to use to replace it if desired, once it has been removed for whatever reason.

Alexa Dawn
12-22-2018, 06:49 PM
Thank you both for the help.

You say that the varnish is removed with solvent, would not the solvent damage the painting?

You say when to apply varnish is measured in dryness, but if it feels already dry when touching it, how would I know if it is completely dry or not or how much time more to wait?

Sorry if those are too much questions, but I want to understand everything so I can work calmly.

DAK723
12-22-2018, 09:24 PM
Yes, varnishing is a good idea, but it is really a personal decision. Some of my work is unvarnished as I prefer a more matte finish. Other paintings are varnished. I think, that if you sell your paintings, that most of your potential customers will expect it to be varnished. But this may not always be the case.

So, no, varnishing is not necessary, but usually preferred.

As Bill mentioned, the newer varnished such as Gamvar can be applied when the painting is sufficiently dry. If you paint thinly, this could be rather soon - a month or two. If you paint thicker, it could take considerably longer. One test you can do is to press a fingernail into a thicker area. If the paint is hard, it is dry. If it is still soft, wait longer.

If you are painting a work that is selling quickly and you don't have time to varnish it, you can tell the buyer that you will varnish the painting is 6 months (or however long). This obviously works best if the buyer is local.

Here is a link to the Gamblin webpage on varnishing:

https://gamblincolors.com/why-varnish/

Don

Alexa Dawn
12-22-2018, 09:35 PM
Thank you very much for your help!!

sidbledsoe
12-22-2018, 09:43 PM
You say that the varnish is removed with solvent, would not the solvent damage the painting?
It depends upon the condition and fragility of the paint film.
The removal of any type of varnish, from any type of painting, can result in disturbing the paint film, including traditional oil paints, I have done it, it has happened to me. Just proceed with caution and always be prepared to retouch if needed.

Raffless
12-23-2018, 04:57 AM
Alexa I've sold a lot of paintings over the years and nobody has come out of the woodwork and asked for the varnish to be removed. Just do a good job of it and fear not.

joel shef
12-23-2018, 05:15 AM
i need to varnish a painting that is dry to the touch but has some small areas of thick paint that is not yet totaly dry but only touch dry (ive painted it 10 days ago). what is the dangours of applying the varnish now (the gallery asked for it a.s.a.p)? (by the way i use gamvar gloss).
thanks.

asdo
12-23-2018, 06:24 AM
i need to varnish a painting that is dry to the touch but has some small areas of thick paint that is not yet totaly dry but only touch dry (ive painted it 10 days ago). what is the dangours of applying the varnish now (the gallery asked for it a.s.a.p)? (by the way i use gamvar gloss).
thanks.I'm pretty sure Gamvar can be applied much earlier than a traditional Damar varnish. From what I remember, Gamvar lets the paint "breath" enough to finish completely drying whereas traditional varnish does not.

According to Gambin >>> "Gamvar Gloss can be applied with a brush when the thickest areas of your painting are thoroughly dry and firm to the touch. Spray application is not recommended."

Hamburgefions
12-23-2018, 08:07 AM
i need to varnish a painting that is dry to the touch but has some small areas of thick paint that is not yet totaly dry but only touch dry (ive painted it 10 days ago). what is the dangours of applying the varnish now (the gallery asked for it a.s.a.p)? (by the way i use gamvar gloss).
thanks.

If I were you I should apply a layer of retouch varnish. Retouch varnis is much thinner as the regular varnish and the drying of your paint layers goes on.

I also have a bottle of Gamvar. I must say it is as thin as retouch varnish. Maybe that is why you may apply Gamvar varnish sooner. I hope not, but you never know.

asdo
12-26-2018, 09:58 PM
If I were you I should apply a layer of retouch varnish. Retouch varnis is much thinner as the regular varnish and the drying of your paint layers goes on.

I also have a bottle of Gamvar. I must say it is as thin as retouch varnish. Maybe that is why you may apply Gamvar varnish sooner. I hope not, but you never know.Gamvar has the consistency of water. Not sure if that's why it can be used earlier than traditional varnish though.

ronsu18
12-27-2018, 01:07 AM
heavy impasto is difficult to varnish because speed is of the essence, but even that is doable with some practise and the right tools (one in each hand...)
there are typically three types of varnish, glossy, satin and matte. you can mix them for desired degree of gloss. a good, very dense and silky soft synthetic flat brush with strongly tapered finish is half the job done.

AnnieA
12-27-2018, 01:37 AM
Just to clarify on the use of Gamvar over impasto areas. Gamblin's FAQ info goes further:
When can I varnish?
Gamvar may be brush applied when the painting is dry to the touch and firm in its thickest areas. For some oil paintings, that may be two weeks, for others, 2 months. To check if it’s dry, gently press your nail into the thickest part of your painting.
It depends somewhat on the pigments used, but if your impasto is heavy, there's a good chance it will fail the test. The retouch varnish idea may work best for you, or, there's a product called Quick Dry that accelerates oxidation (this is what really happens to paint as it "dries"), and dries glossy. You also can attach something to your painting and say that as a recent painting, it will need a final varnish coat at six months or so and that you as the artist are willing to do it if the painting can be returned to you for a short time.

Hamburgefions
12-27-2018, 09:42 AM
Gamvar has the consistency of water. Not sure if that's why it can be used earlier than traditional varnish though.

That's what I think. But this also means, that if they thin it like water, it's more a retouch varnish, rather than a final varnish.

AnnieA
12-27-2018, 02:21 PM
That's what I think. But this also means, that if they thin it like water, it's more a retouch varnish, rather than a final varnish.
No, it's definitely a final varnish, not a retouch varnish. It's not to be used with water at all.

asdo
12-27-2018, 09:26 PM
No, it's definitely a final varnish, not a retouch varnish. It's not to be used with water at all.Hamburgefions said thin it "like" water. No water is used.

asdo
12-27-2018, 09:29 PM
That's what I think. But this also means, that if they thin it like water, it's more a retouch varnish, rather than a final varnish.A final varnish coat doesn't have to be super thick and glossy to protect the paint. All it takes is a very thin coat. That will also make it easier to remove for changes or cleaning later on. The social media videos of "varnishporn" where they dump half a bottle of varnish on a painting and let it drip over the sides is a disturbing trend. :confused:

sidbledsoe
12-27-2018, 10:11 PM
I also have a bottle of Gamvar. I must say it is as thin as retouch varnish.
Gamvar lets the paint "breath" enough to finish completely drying

So it is as thin as water, remains porous, and can be easily removed with the very weakest spirit solvent available, that sounds to me more like a traditional retouch than it does like a traditional varnish.
Mary often checks out the threads here about varnishing, what say ye Gamblin?

chamisa
12-28-2018, 08:42 AM
On the Gamblin varnishing page it states:

“During the painting process, it can be beneficial to even out the surface quality to better evaluate the values of the painting and deepen the color saturation. We recommend “oiling out” the surface of the painting with a mixture of Galkyd painting medium and Gamsol for this. As the small amount of painting medium will bond permanently to previous and subsequent layers, this procedure is preferable to using retouch varnish. “Oiling out” has its benefits on a recently completed painting as well, since it not only unifies the surface quality but it reduces the absorbency of paint layers – allowing the subsequent varnish layer to remain on the top-most part of the painting structure.”

Wouldn’t the above oiling out then not need a retouch varnish, or is there still sinking in of colors later on?
Also, when I’ve used Liquin as a medium, I’ve noticed I have less sinking of dark colors and a slight overall sheen when finished which doesn’t seem to dull even after a couple of years.

contumacious
12-28-2018, 02:52 PM
That's what I think. But this also means, that if they thin it like water, it's more a retouch varnish, rather than a final varnish.

Gamvar was formulated from the get go as a Removable Conservation Final Varnish. Using it any other way is not recommended by Gamblin from what I have read and will likely cause some serious paint film adhesion issues if you do.

Found on the web:

"Retouch Varnish is used during the course of the painting. Final Varnish is used at the end of the painting.... Retouch varnish can be painted over and retouch varnished again many times."


Gamvar most definitely is NOT a retouch varnish based on what I understand a retouch varnish to be and should not be used as such, nor should you use it to "oil out" your painting. It dissolves readily with very weak solvents - Gamsol, one of the weakest OMS formulations, being the one Gamblin recommends. If you put any paint over the top of Gamvar, it will not have a permanent bond with the rest of the painting and will likely come off with a light application of OMS.

sidbledsoe
12-28-2018, 03:38 PM
One of the two old uses for retouch was for use during painting, that has been deemed to not be a good practice by conservators, etc. especially with the newer types of modern varnishes such as Gamvar. So no type of varnish is recommended for interleaving layers anymore.

The other use of retouch was, and still is, for a temporary varnish for a completed painting, applied sooner, while awaiting full paint film curing for final varnishing 6 months to a year later.
This is still considered to be an ok practice, and Gamblin is varnish that is recommended to be applied soon, like a retouch varnish, but it still allows the paint film to further cure.

So lets compared to Gamvar to another popular synthetic varnish, Soluvar by Liquitex,
for use with oil paint, they recommend waiting 6 months to a year, just like any traditional varnish, you should not use it for an isolation coat, and it is not soluble at all in OMS (Gamsol, etc.).
They recommend using turpentine to remove, or test removal with strong mineral spirits as it may or may not work depending upon the strength.
Between the two, it sounds to me like Soluvar is totally more like a traditional varnish, while Gamvar seems to be more like a watery thin retouch varnish, and that the Soluvar would provide a stronger and decidedly more durable protective coating than what the Gamvar product provides.
What do you think Gamblin?

contumacious
12-28-2018, 04:46 PM
The major difference between Gamvar ( I don't know about other brands of removable conservation final varnishes) and various products listed by their maker as "Retouch Varnish" are as follows from what I have gleaned. Perhaps the folks at Gamblin can shed further light on this but my guess is they will agree with the following, at least as far as Gamvar goes:

Gamvar - Not recommended or endorsed by Gamblin to use as any type of retouch varnish or when additional layers of paint or any permanent type layers will be applied. It is represented by Gamblin to use as a removable final varnish on a finished piece that is sufficiently cured, to protect the finished piece from environmental polutants such as dirt, dust, airborne contaminants etc. When the layer of Gamvar becomes soiled, you remove it and apply a new protective layer. It also is recommended by them for unifying the sheen of a finished painting - not one in progress that will have more layers added.

Retouch Varnish - These products labeled as Retouch Varnish are currently recommended and likely will be down the road by their makers to use on an unfinished painting that will see more layers of paint applied on top of the retouch varnish. Remember that not ALL Retouch Varnish offerings contain Damar or other Natural Resins. Some of the Retouch Varnish makers say it is OK to use multiple layers of their product, with each application followed by fresh paint, then lather rinse repeat as often as you like. Some of the Retouch Varnish makers as far as I have been able to find, do not warn the consumer that their retouch varnish might not play well with solvents or solvent removable final varnishes. If their Retouch Varnish contains natural resins, they SHOULD have that warning on their product in my opinion since we do know from trusted sources, that if they contain Damar or other Natural Resins, using retouch varnish between paint layers MIGHT cause problems later if / when solvents are used to clean the painting.

The bottom line here is that the artist is responsible for what they choose to use in their paintings. If you want a removable varnish that comes off easily without damaging your painting you should test whatever you end up using. I have tested Gamvar many times and have never had any appreciable amount of paint come off when removing it. I have only seen very slight traces of color on the cloth, which can happen from rubbing a fully dried painting with a dry cloth containing no solvents of any kinds. Your mileage may vary as the saying goes, so TEST before you rely on a product to do what you expect it to do.

Dcam
12-28-2018, 05:44 PM
Nice to see that they now have a Satin and Matte Gamvar. I'm not always in love with gloss.

AnnieA
12-28-2018, 05:50 PM
Hamburgefions said thin it "like" water. No water is used.
Does one ordinarily "thin" water? Did he mean thin to a water-like consistency? It doesn't seem that much of a reach to think he meant to use it with water. Sorry if I misunderstood, but it was a little unclear.

sidbledsoe
12-28-2018, 09:36 PM
quotes from MITRA, they don't recommend using retouch nor any other type of varnish for layering purposes:
his use of isolation varnishes in oil painting should be discouraged for a number of reasons. First, it is generally a bad idea to reduce the mechanical tooth of a paint layer, which could promote delamination or flaking of the superimposed layer.

Second, adding the varnish layer between paint layers will introduce an unnecessary solubility issue. Even if it is covered by additional oil layers, the varnish could be attacked and undercut during a restoration campaign resulting in the loss of all subsequent layers. For instance, a layer of natural resin between paint layers will create a paint stratigraphy that is sensitive to hydrocarbon solvents, even those containing a low proportion of aromatics. A layer of shellac between oil paint layers introduces a sensitivity to alcohols, etc.

Additionally, the use of varnish interlayers creates a more complicated paint stratigraphy. We know from examination of historical paintings that the more complicated the stratigraphy, the more likely there will be some failure in the future. This does not mean that one has to create paintings in only a few layers, but you should aim to use as few layers as is necessary to create the desired effect.

The varnish interlayer will also respond in a different manner to movement of the substrate than will the paint layers below and above it. It will also age differently. The flexibility of the varnish may change drastically over time making it less flexible than the layers that it is covering. Etc, etc. So, for the above reasons, and likely many that I am not thinking of at the moment, it is really best to avoid the use of isolating varnishes in oil painting.

Brian Baade

also I think Hamburg meant that if Gamblin thins their varnish, Gamvar until it is as thin as water or like water, then is sounds more like a traditional retouch varnish.

AnnieA
12-29-2018, 03:23 AM
...also I think Hamburg meant that if Gamblin thins their varnish, Gamvar until it is as thin as water or like water, then is sounds more like a traditional retouch varnish.
Oh yeah, and I can see that now. I just wanted to also mention why I misread it. No worries - we've got it straightened out now.