7 Questions every Artist needs to ask before Varnishing an Oil Painting

how-to-varnish-oil-painting

An Introduction to Varnishing an Oil Painting

As we’ve discussed in 3 Reasons why artists varnish their work (and why some artists don’t) varnishing is primarily an aesthetic choice on the final finish of your painting.

Not only can it really bring up the vibrancy and richness in your realist paintings but it offers protection for the painted surface from atmospheric effects to make the surface easier to clean in the future.

No One technique for varnishing suits every situation — the texture of the paint surface, whether you want a matte or gloss finish, speed of completion etc.. all effect which varnish you choose.

There are different considerations to think about when you’re working with Oils in comparison to Acrylics, so here are some common questions to check before getting out the varnish brush…

1. How long should I wait before varnishing an Oil Painting?

When you’re varnishing an oil painting it really depends on how thick or thin the paint application is. So if you work in very thin layers it dries a lot quicker than if you work impasto with thicker blobs of paint.

The other thing to consider when using Artist quality paints is which pigment you are painting with – if it’s a quick drying or slow drying pigment.

For example, if you’re using Alizarin crimson or Ivory black which are very slow drying, (there is a lot of oil used in the binding process of the oil paint) it would take a lot longer to dry compared to if you used a fast drying paint such as Raw umber which has a lower oil content in it. Earth colours such as Raw umber dry a lot quicker.

Pro tip: Some brands of student quality oil paints contain driers in their slower drying pigments in order to bring the drying times closer together.

Drying rates tend to average out as colours are almost always mixed on the palette, so the drying times tend to equalise to a great degree.

N.B This is just a reference to traditional oil paints and different drying times of each pigments, I’m not referring to ‘Quick drying oil paints’ that dry within a day.

The Drying or Curing Process

Traditional oil paints dry by oxidization, when the oil reacts with oxygen in the air. There isn’t any water in the paint to evaporate (unlike acrylics which dry by evaporation).

The pigments in oil paints are dispersed in oil, which may itself be dissolved in a solvent and that solvent evaporates away when the paint dries. which can be dissolved in a solvent, this solvent evaporates away when the paint dries.

This leaves the pigment and oil behind.

The oil doesn’t evaporate, the linseed oil and pigments oxidize, meaning they react with oxygen and harden.

Which is why you shouldn’t varnish an oil painting with traditional varnish until it is fully cured as putting varnish on a touch dry painting won’t allow air through the varnish layer and will stop it drying properly and fully.

So how long would it take for a painting to be touch dry on the surface?

If you have very thin paint application with earth colours, an oil painting can be touch dry within a day or two for a thicker painting with other pigments it may take 10 – 14 days.

How long would it take for a painting to be fully cured/dry?

If you have very thin paint application with earth colours, an oil painting can be fully dry within a couple of months but for a thicker painting it may take 6 months or as long as 2 years.

For most artists waiting 6 months or a year to varnish can seem a bit excessive, especially if the piece is for an exhibition or a commission that you can’t easily revisit to varnish at a later date.

There are some modern synthetic varnishes that are now being manufactured that have the benefit of allowing the oxidation process to take place through a permeable varnish layer applied to a touch dry oil painting.

This allows artists to varnish their work after only a few weeks, whoo hoo!!

What is the worse that could happen if you varnished a touch dry but not fully cured painting using a traditional varnish?

The worst that could happen would be that your varnish layer would crack as the paints contracts as it dries, however, this would really only be most apparent if you painted with a very thick application of paint. Also, the oil wouldn’t be able to fully harden so it wouldn’t be a super strong bond between the layers.

It’s always advisable to follow good professional practice for the conservation of your pieces if you’re using traditional varnishes.

2. Do I need to apply an isolation coat with an oil painting?

No, you don’t need to apply an isolation coat to an oil painting.

Once the oil paint is dry enough then you can apply the varnish directly to the painting surface. This is because if you ever needed to remove the varnish at a later date, the solvents used to remove the layer of oil varnish won’t damage the existing oil paint layer.

On an acrylic painting this differs as the isolation coat adds a much needed sheet of thin protection over the paint surface.

3. What’s out there? – Traditional or Synthetic Oil Varnishes

dammar varnish

Traditional Natural Varnishes:

Dammar, Copal, Amber, Mastic

Traditional Natural Hard Varnishes

Copal and Amber varnishes, referred to as a hard varnishes, was used by the Old Masters.

They are a lovely Golden colour and as such, give a rich glossy and enamel-like appearance. However, they are susceptible to cracking, extensive yellowing and become increasingly difficult to remove from a painting over time.

Generally they’re harder to come by or they simply do not exist as they are the fossilised remains of prehistoric tree sap and many of them have been mined to extinction.

Hard varnishes do not redissolve in a solvent such as Mineral Spirits or Turpentine. They must be dissolved in hot oil which can get a tad complicated!

True hard Copal and Amber varnishes are rare in the world today, some specialist manufacturers still offer unique historically-accurate painting varnishes if you want to go completely old school.

Traditional Natural Soft Varnishes

dammar varnish oil painting

Dammar (can be spelt Damar) and Mastic varnishes are referred to as soft varnishes, they dissolve in solvents such as Turpentine and Mineral spirits.

This means soft varnishes are still removable from an oil painting surface without greatly affecting the paint layers below.

Pro-tip: To dilute the Dammar varnish you ideally need to use Turpentine which is better suited to a well ventilated separate studio space, rather than a ventilated room in a home. Odourless Mineral Spirit (OMS) is not strong enough to dissolve the natural resins of Dammar.

Dammar varnish comes from tree resin and is paler than Copal but has great viscosity and is still used commonly in oil painting today, the visual aesthetic look of Dammar has a luscious quality to it similar to the historical hard varnishes.

The issue that can come with Dammar (because it’s a natural resin) it has a tendency to yellow over time and as it dries it becomes more brittle, leaving your canvas more likely to crack if the canvas is knocked.

Pro tip: I often use Dammar in the final layers of an oil painting as part of the glazing medium because it really goes on so nicely and has a nice translucent quality when you first apply it. The advantage of using the Dammar varnish in the final glaze helps to make the medium leaner than if we just used Linseed Oil. It also saturates the colour a lot more than if we just used Turpentine or Mineral Spirits to dilute the paint consistency. Because we mix the Dammar varnish with Linseed Oil in the glaze medium, the flexibility of the Linseed Oil balances out the brittleness of the Dammar varnish.

All that aside, it’s a personal choice as an artist and for some of my paintings I like the idea they will have that lovely soft, warm yellow glow to them in the future.
I use the choice of varnish as an aesthetic judgement, it might not be as technically sound as keeping a crystal clear finish that the synthetic varnish would give but I just like it.

A note to newcomers to Dammar

I usually apply Dammar varnish to smaller paintings as it can go very tacky, very quickly and is harder to control with a brush.

Dammar is most commonly used in liquid form and applied with the brush, however, if you’re after a really super smooth finish it can also be found in aerosol can form and used as a spray application.

This can be very effective to get a smooth finish if you’re not used to applying with a brush. You’ll get more product wastage and you need a really well ventilated space or a very still dry day to work outside, but the results can be very smooth.

New synthetic varnishes:

synthetic satin matte varnish

MSA, Gamvar, Alkyd Synthetic Resins

The synthetic varnishes offer a lot of advantages over the traditional natural varnishes

A clear coat on first application that stays clear over time, therefore non yellowing and more flexible.

They are available in liquid or aerosol form, are readily available and cost-effective and they come in a variety of sheens, such as matte, satin or gloss.

They also allow for relative easy removal with less risk to underlying paint layers.

Alkyd Synthetic Resins such as Schmincke Picture Varnish provides a glossy, non-yellowing, colourless, highly resistant top coat. (most similar to a hard varnish) Must be applied after 8-12 months.

Mineral Spirit Acrylic varnishes (MSA’s) have a high molecular weight tend to offer a better protective surface, have greater elasticity and more resistance to blooming. Must be applied after 8-12 months.

A quicker finish

Some recent varnishes also have the great advantage of being able to be applied when the painting is just touch dry – rather than waiting for the painting to be fully cured.

Gamblin make a varnish called Gamvar which has been developed specifically for this purpose.

It either comes in two parts system or premixed by Gamblin.

You can only brush or sponge apply it, as it is not available in spray form, however, it’s a lot easier to apply than Dammar because it has a longer working time when you’re brushing it on.
Sponge application can also give a smooth finish and enable you to keep your materials super clean by using the sponge once and then throwing it away.

GAMVAR

Gamvar saturates and gives greater depth to the colors in your painting and gives your work a unified and protective semi-gloss surface. Developed in collaboration with the National Gallery of Art, Gamvar goes on water-clear, stays water-clear and can be easily and safely removed with Gamsol. Gamvar is virtually odorless and ready to apply.

Gamvar can be applied when the thickest areas of your painting are thoroughly dry and firm to the touch.

The greatest advantage of the Gamvar varnish is the ability to apply it when the painting is touch dry. This is a revelation when varnishing an Oil.

If you’re painting with more impasto oils you’ll still have to wait for the paint to be stiff under your touch to prevent shrinkage.

You can read more specific FAQs on Gamvar Varnishing Help here:

4. What is ‘Sunken in’ and ‘Oiling out’?

retouch varnish

Sometimes you can find areas of your painting that have turned dull, matte and lighter in colour, even though surrounding areas are still glossy and rich. This is where the oil from the paint has soaked into an absorbent ground and left just the pigment on the canvas surface. This is referred to as a ‘sunken in’ area.

There are a couple of main reasons why it happens:

1. Too much solvent or Turpentine in the paint mix
2. A cheap Gesso, a too absorbent or an unevenly absorbent ground

The two options you have to restore an uneven sheen to your painting before final picture varnishing are:

1. ‘Oil out’ the surface – this is a method of applying sparingly a thin coat of Linseed oil or clear artist medium over the entire surface of the painting.
The painting must be touch dry and then you can apply the oil with a clean, lint-free rag or paint on with a soft brush and then remove most of it with a rag.

Video demonstration of Oiling out an oil painting using a Clear Artist Medium – Windsor & Newton

Video demonstration of Oiling out an oil painting using Galkyd and Gamsol – Gamblin

2.  Apply a Re-touch varnish – Re-touch varnish is a standard Dammar varnish that has been diluted with Turpentine by the manufacturer.

It can to be used during the course of a painting and as a temporary picture varnish to restore colours and add an even sheen to your painting yet still allow the oil to dry fully.

Also, you can paint over the top of a Re-touch varnish.

To apply it, the painting must be touch dry and I’ve found it is most effective as a spray because you can build up the layers gently, compared to applying with a brush.

If you were to apply the final picture varnish directly on top of your painting without oiling out first, all that will happen is the glossy areas will look more glossy and the matte areas will only look a bit more glossy – so you’ll still have the difference in sheens between the two.

clear retouch varnish

Notice the difference in colour between: Re-touch varnish, refined Linseed oil, Dammar Varnish.

Pro-tip: If the difference in sheens is very minimal then you don’t have to oil out, you can go straight on with the final picture varnish.

5. Will the varnish even out the sheen of my painting ?

If you have a minimal difference between matte and gloss areas, then yes it will.

If you have obvious, larger areas of different sheens then see ‘Oiling out‘ above, as the varnish on its own will only emphasize the differences.

Matte Varnishes

beeswax varnish

For oil painting, the matting agent that is usually added to the gloss varnish is a wax. You can mix in different quantities of wax to change the sheen of your varnish.

You can also apply Cold Wax Medium straight to your painting and then buff it up with a rag and this will give you a very slight lustre to your finished work.

This can be easier to apply than using a brush with Dammar or Synthetic varnishes as the product is in a wax form – similar to adding wax polish to a table.

However, for realist paintings when you are trying to bring out colours and form in your work, the matte varnish will dull, desaturate and flatten out the three-dimensional effect and colours of the painting. If you’re painting more abstract or impressionistic style works, it can work really well.

www.coldwaxpainting.com is a great resource on Cold Wax Medium techniques.

6. Do you have to Varnish an Oil Painting?

If you’ve followed all the rules of oil painting:

  • Fat over lean
  • Slow drying over fast
  • A well-primed, well made support

You’ll have a stable, durable paint film that doesn’t necessary need a varnish, so no, you don’t have to varnish an Oil painting.

However, varnishes can be used for both their aesthetic and protective properties:

  • Change the surface finish to gloss or matte
  • Provide a more unified finish to the various areas of a painting
  • Increase colour saturation
  • Provide protection for the paint surface
  • Allow for ease of cleaning
  • Provide protection from UV radiation

7. Do you have to dilute the varnish and how many coats do I apply?

MSA acrylic varnish

It depends on the different brand or type of varnish that you’re using.

For example, MSA varnish needs to be diluted with Turpentine before applying and if using a brush application is best applied with a few thin coats.

Winsor & Newton’s gloss varnish can be applied straight from the jar so read the manufacturers instructions carefully as to understand fully the product you are working with.

When using a spray varnish if you work in several layers, you can judge the sheen and increase the gloss level the more coats you apply. A sprayed coat of varnish will dry within 10 minutes and subsequent coats can then be applied, always allow the previous coat to dry first.

The more coats that are applied the richer and deeper the colours will be.

How to apply a varnish with a brush

Warm the canvas next to the radiator to make sure there is no water in the canvas to prevent blooming.

1. Get a clean, wide brush – I usually use a 2 inch flat nylon brush, you can use a ‘varnish’ brush but it is not essential. I wouldn’t recommend a decorators brush as it will show too many brush marks, you want a brush that is smooth to the touch so you can just glide it over the surface.

2. Pour out some varnish into a shallow dish. It is easier to control the amount of varnish on your brush this way.

3. Lay your work on a board -I use a piece of mdf, or newspaper, you are bound to get some overspray and/or drips.

4. You need to work quick but gently – Apply in long even strokes to cover the surface top to bottom while moving from one side to the other.

5. Work side to side, left to right, slightly overlapping each stroke – you are aiming to have no visible brush-marks

6. Once you leave an area, do not go back over areas that you have done. If you do, you risk dragging partially dry resin into wet, which will dry cloudy over dark colors. If you missed any areas, allow to dry completely and re-varnish. 3 thin coats is better than 1 thick one.

7. After varnishing. I often cover my painting with a board slightly larger than the canvas, resting it on props so it hovers and reduces the amount of dust that could fall on the wet varnish layer. Alternatively with large canvass I will prop them facing a wall when the varnish is semi dry.

How to apply a spray varnish

  • Warm the painting so that there is no moisture on the surface – make sure varnishing is never done in a damp or very cold environment.
  • Have the spray can at room temperature – not straight out your outhouse or garage.
  • Wipe over the surface with a lint free cloth. Make sure it is clean and dry.
  • Place your painting vertically in a dust free room. This is very important, it won’t attract as much dust as horizontally and prevents you from being over heavy handed – creating runs.
  • Place your painting on top of a board that is larger than the canvas.
  • Shake, Shake, Shake… and then shake some more. This is the bit you read on the back of a can and then shake for 10 seconds and eagerly start spraying. Put a timer on your phone, anything to ensure you shake that can for 2 minutes, it’s worth it for an even finish.
  • Apply the spray at an even distance away from the canvas. At least 40 cms away, it’s a natural tendency to move your arm closer to the canvas, so just be aware of this.
  • Regularly check the nozzle for blockages. It’s the nature of spray varnishes to become blocked really easily but I keep a rag next to me and a practice canvas so I can clean the nozzle, check the spray flow on the practice canvas and go again for real. I find I have to do this several times when I’m spraying a varnish.
  • Shake, Shake, Shake… and then shake again.
  • Over spray the edge. Start before the canvas and finish after the canvas spraying the board underneath. This ensures an even coverage.
  • Work in thin layers. 2-3 layers should be fine, a sprayed coat of varnish will dry within 10 minutes and subsequent coats can then be applied, always allow the previous coat to dry first.
  • As many as 20 – 50 coats can be applied for a super glassy effect.

You might also like:

1. 3 Reasons why artists varnish their work (and why some artists don’t)
2. How to apply a varnish to an Acrylic Painting

 

 

This Post Has 135 Comments

  1. Thank you very much. Very helpful information!

    1. You’re welcome Lazar, pleased you found it helpful.

      Cheers,
      Will

    2. Wow, I don’t know how you manage to pack so much info in and make it so accessible… but you’ve done it again :) Many, many thanks Will. Really useful and so kind of you to down load it for free.
      I look forward to the ‘more oil specific tutorials’ you mention (in reply to Steve).
      Cheers, Carol

      1. Thanks Carol, pleased you found it easy to follow, Varnish can have a lot of considerations.

        Cheers,

        Will

  2. Great informative post as usual. It would be great to see an expansion of the oil painting section. Any future plans?

    1. Thanks Steven, yes, there are plans for more oil specific tutorials in the future.

      Cheers,
      Will

  3. Very informative. Thank you for the information and especially the demonstrations.

  4. Hi Will,

    Thanks for latest email – packed with useful information as usual. Any and all info on oil painting is most welcome.

    Cheers

    Elaine

    1. Thanks Elaine, pleased you found it helpful.

      Will

  5. Will, thank you for your information,
    I enjoy reading and learning. I don’t really know to much about art work or painting, I have started a painting of Jesus, I think I’ve done pretty good for a first time. I didn’t even know how to draw. I sit and study what it was looking like and could see things that I could improve on. I picked you out on u- tube, and have learned some things there that helped. I would like to send you my picture and get a opinion. If you don’t mind let me know. I want him to be perfect .
    Thank you again,
    Melva

    1. Hi Melva, so pleased you’ve been finding the articles helpful in your paintings.

      Cheers,
      Will

  6. That was brilliant! Thanks for sharing your knowledge!

  7. Hi Will

    I always take pleasure in reading every detail of yo lessons and approaches this has provided a room for tremendous improvement in the way l exhibit my art works.

    Thanks a lot Be Blessed

    Regards Kevin

    1. Thanks for your kind comments Kevin, pleased you found it of interest.
      Cheers,
      Will

  8. Thanks for the info Steven, I took art classes at the local museum art studio 2 years ago, the instructor only referred me to the Golden Varnish, which was good, however difficult to work with. The range of varnishes you told us about is wonderful. Thank you again.

  9. What can I say, thank you Will for your detail advice!

    Best

  10. Hi Will,

    Thank you very much for the informations, I am usually shy to leave comments or ask a questions but I follow to your website and I found it very helpful.

    Best

    Mehtap

    1. Hi Mehtap,

      Lovely to hear from you, and thanks do much for taking the time to comment on the article, so pleased you’ve been finding the articles helpful to your painting.

      Cheers,

      Will

  11. Hi Will,
    Thank you so much!! I Love this! I think I missed something. You mention diluting Dammar varnish with Turpentine, however I noticed Winsor & Newton’s Dammar Varnish contains Turpentine. I am not thinking of the ( W & N’s, Artists Glossy Varnish). Should I still dilute this Winsor & Newton Dammar? How much if so? I would like so to use this Soft Traditional Natural Varnish. It says just to warm. Also, would I dilute a copal picture varnish brilliant gloss? It seems fairly thick. I would like so to use this too as I have! Just one more. I have an Ageing Varnish that goes over a Cracking varnish, the Cracking that I do not use. Do you know of any use for this without the Cracking Varnish? Thank you so much Will! You are the best! Jeff Nelson

    1. Hi Jeff,

      In relation to diluting Dammar:

      Pro-tip: To dilute the Dammar varnish you ideally need to use Turpentine which is better suited to a well ventilated separate studio space, rather than a ventilated room in a home. Odourless Mineral Spirit (OMS) is not strong enough to dissolve the natural resins of Dammar.

      This is when diluting it for a glazing medium, The Winsor and Newton is ready to go from the bottle.
      The cracking varnish is often used for decorative effects, I personally don’t use it.

      Cheers,

      Will

  12. Thanks Will, very helpful information.

  13. Hi Will! Fantastic article, as always. I was wondering, how do you choose reference photos? What aspects are you looking for in a reference photo?
    Thanks! :)

    1. Hi Cait, If I’m using a reference image I’m just trying to look at the image as if it was a object/scene in-front of me. So depending on the subject and mood/feel I’m after with the painting I’d change the aspects within the image.

      Cheers,

      Will

  14. What varnish is used to obtain an ENAMEL effect on oil and acrylic paintings ?

    1. Hi Stuart, Copal varnish will give you an enamel effect on oil paintings. Although any gloss varnish built up in many layers will also give you an enamel like effect.
      Cheers,
      Will

  15. Hi Will,

    I have a large oil painting on wood. I basically painted with fast drying oils in thin washes, using liquin as medium. I’m now struggling with what to use for varnish. I’m quite concerned that the combo of fast dry oils plus liquin will mean cracking if I varnish.
    This may sound crazy, but I had heard that minwax polyacrylic will work as a top coat. Tried it on a couple small test pieces and so far these pieces look fine. Since the big piece is a commission, I’m concerned about going that route yet all the varnishes worry me with the combo of fast drying oils and liquin. Did I ruin this thing in the first place by using the fast dry oils and liquin? Is there hope? Have you heard of artists using things like polyacrylic over oils?

    1. Hi Cara,

      Fast drying oils are essentially standard oils mixed with Liquin.

      Liquin is an Alkyd Medium and fast drying oils are Alkyd paints, so it will be safe to varnish in the traditional manner. I personally wouldn’t use an acrylic based topcoat over any oil paintings, fast drying or traditional.
      Hope this helps,

      Cheers,
      Will

  16. Thanks for the informative article. I realize this may take up to a month to dry but I’m wondering if literally pouring Gamvar over the surface of my 36×36 in oil on gesso board will create the smooth top pool layer I’m looking for. After several paintings I’ve tried to keep the paint stroke birms very shallow or nonexistent in order to have a smooth plane that a glossy varnish won’t have ripples in its sheen. I’ve painted a masterful piece but there is always ( i since I’m not Dali yet) small birms around that varnish layer wont clear. Its frustrating and I’m considering pouring a shit load of gamvar on top and waiting till the puddle dries.

    1. Hi Neal, personally I would go for the pour on puddle technique, but you could always email Gamblin to see if there will be any adverse effects.
      Hope this helps,

      Cheers,
      Will

  17. Hi Will,

    First of all, a big thank you for the wealth of information on this site.

    I find all of the different oils and mediums fascinating, but it can be a bit complex at times.

    I want to oil out some paintings to even the surface, but as most mediums seem to contain turpentine I am concerned that the turpentine in the medium will break down the paint when I apply it to the painting. Are my fears unjustified? Would it be possible for you to suggest a safe formula?

    Thanks

    Terry

    1. Hi Terry, have a watch of the videos above and you can see a couple of alternatives using artist painting mediums.
      Cheers,
      Will

  18. Thanks Will,

    I did look at the videos, but I was a little concerned about the linseed oil. Having watched them again I’ll go for the Winsor and Newton medium as it’s more readily available. I’ll try it out on a less successful painting first!

    Terry

    1. Good one Terry, the Winsor and Newton medium works well.
      Cheers,
      Will

  19. I would like to redo an oil painting from a few years ago. The piece has a brushed on varnish but i dont remember what i used. Can I pint over it?

    1. Hi Elizabeth, yes you can paint ontop of it, ideally you would remove the varnish first and them paint ontop.
      Cheers,
      Will

      1. Fabulous! Just need to fix a bit in the background! Thank you for replying!

        Best,

        Elizabeth

  20. Brillian coverage of a tricky procedure which have struggled with for many many years. Thank you for your clear and well explained pointers.

  21. I have an oil painting that I applied Gamvar picture varnish. It really brought out the colors…but is very glossy. What can I apply over that to bring down the high gloss but not lose the vibrant colors and dark background?

    1. Hi Patti, you can mix Gamvar with Cold Wax medium to take down the sheen to a more satin finish and then apply another coat.
      Hope this helps,

      Cheers,
      Will

  22. How long does it take the Winsor & Newton varnish to dry? Can’t seem to find out.
    Since it’s not mentioned on the bottle, or in other places — I presume it can’t be too long.
    Need to varnish my oil painting, frame it, and put it in a show. But time is running out.

    1. Hi Dick, it depends on how thick you apply the varnish but a thin layer should be touch dry in a few hours, ideally left overnight before adding a frame. Good luck with the show.
      Cheers,
      Will

  23. Hi Will,
    Wondering if you have any recommendations for a varnish that is relatively easy to obtain (blick, jerry’s, etc.) that will produce the highest gloss effect, for large-scale oil paintings? I’ve used Gamvar in the past, applied three coats, was pretty satisfied, but wondering if there’s anything else that will produce an even higher gloss result? Winsor & Newton high gloss varnish has been recommended to me. I am ok with doing multiple coats, just want something that’s easy to put down and will give the colors the brightest pop, with the high-gloss. Thank you!
    Brandon

    1. Hi Brandon, the Winsor & Newton high gloss does give a great high gloss finish, you’d be hard pushed to achieve a more glossy effect. It’s often a case of applying more layers than you think, i know of some realist painters that apply up to 20 coats of varnish so the painting appears like you’re looking through glass to the painting. it can be prone to cracking if knocked due to the high number of coats, but the effect can be fantastic

      Cheers,
      Will

  24. Thanks so much. This was super helpful to me. I tend to not like the surface of my dried paintings and had no idea that I didn’t have to wait a year to varnish them. I was told this in art school, and maybe it is a good practice…but in today’s world it is far too long. One thing about retouch varnish is that if you read the contents, I seem to recall that it has map gas in it. It is a fairly dangerous can, store this properly.

  25. If I have painted picture with oil figures on an acrylic background and I varnish it as if it is an oil painting will the background acrylic run, or will it accept the varnish?

    1. Hi Ramona, the acrylic won’t run when you apply a varnish.
      Cheers,
      Will

      1. Thank you very much for the information Will. That is good to know.

  26. I have an oil painting that I’m wanting to wax and buff to a high sheen. I am not sure if this is possible. I’m trying to avoid other varnish and just apply wax, gently rub in, buff out. Is this a bad idea? Basically, I want the burnish effect and a transparent top coat. Thanks

    1. Hi Jade, if you use a cold wax medium and then buff with a cloth that with give you the effect you’re after.
      Cheers,
      Will

  27. Great! Thanks

  28. I noticed when I varnished two paintings, one a plain oil painting, and another an acrylic painting with a gel isolation coat, and I used Gamvar varnish on both paintings, the oil painting had a lot of dust stick to it, but the acrylic painting with the isolation coat came out dust free and smooth in the same setting, time and place that they both received gamvar. I later removed the gamvar from the oil painting with mineral spirits and no harm was done. Do you think Oiling Out can serve the same as an isolation coat for an oil painting to keep the dust down when applying gamvar later?

    1. Hi Jan, interesting to hear about the two applications next to each other, I haven’t tried an oiling out and then varnish as would always just varnish straight on top and keeping the amount of oil on the painting to a minimum to prevent excessive yellowing of the colours in the final layer. I’ve had success in the past with re-touch varnish and then a Gamvar finish if you’re going for a gloss finish. The retouch varnish works like an isolation coat, it also does a good job on its own, you can see a video of brush application here
      Cheers,
      Will

      1. Thanks for your replies will. I did try the oiling out method on a small painting and it worked to level the surface for retouch varnish as I thought. It seems to me now that it is not so much what is put onto the painting as preparation, but that it is applied with a piece of cloth that is massaged into the surface. Maybe oil worked, but then maybe also just putting gamvar varnish on a rag and massaging the surface first could be a preparation for a second coat with a soft hair-bristle brush.

        1. Hi Jan, yes a very subtle coat of Gamvar applies with a rag would work and dry off very quickly for the second layer.

  29. Hi, I have a question about the Gamvar. Can I use it over workable varnish, and/or varnish? Or do I have to strip the painting first? If I have to strip, which remover will work with dammar? Thanks, Jackie

  30. Great article. I’m very interested in the new synthetic varnish that you mentioned is being developed. To be able to apply a final varnish which still allows a touch-dry oil painting to continue oxidizing seems too good to be true. I’ve looked for any word of such a product on line but I don’t see anything. The only option at the moment seems to be retouching varnish. Can you offer any more information on that? Thanks!

      1. Thank you so much Will! I appreciate it!

  31. Hi will, you mention putting dammar varnish in a final glaze. Can I assume Gamvar can be used similarly?

    1. Hi Jan,

      I wouldn’t use Gamvar as a glaze medium, just as a final picture varnish.

  32. Hello Will,

    I have just read your information on varnishing oil paintings. One question, can I use an acrylic varnish like those produced by Winsor and Newton to protect an oil painting.

    Kind regards,
    Greg

    1. Hi Greg,
      The Winsor & Newton Varnishes can be used (this is from the Winsor & Newton website – ‘All Winsor & Newton varnishes can be used on oil, alkyd, Artisan or acrylic paintings’) If you check on the label of the varnish it will be listed if the varnish is suitable for oils and acrylics.
      Cheers,
      Will

  33. Hi Will, I love that there is so much useful information on your site. I am new to painting and it is always a place I visit to pick up tips and increase my learning. I am nearing completion of my first oil painting, but it has a patchy look and I think I need to oil it out.

    On Oiling Out, you mention that this can be done by “applying sparingly a thin coat of Linseed oil” but I don’t know what a thin coat would be. Could you give me a ratio of parts Linseed oil vs parts thinner, which I am assuming would be Turpentine or Mineral Spirits?

    1. Hi Louise, nice to hear from you, you can see a couple of example of oiling out in the videos in the article, for oiling out just with linseed oil use the pure oil in a super thin layer. You can use a cosmetic makeup sponge (like this) to apply it thinly to the surface, or just use the medium you are using at that stage of the oil painting.

      Cheers,
      Will

  34. Hello, please help!
    I bought a large 5×5 foot oil painting. It hung on a wall for 3 years unvarnished. It is very dusty and dirty.
    I’m going to gently vacuum it.

    1. How do I clean it before varnishing?

    2. Most of the canvas has no paint whatsoever on it. It is a fabric canvas, is it okY to varnish unpainted canvas?

    Thank you!

    1. Hi Ji,

      1. How do I clean it before varnishing?
      With a slightly damp lint-free cloth

      2. Most of the canvas has no paint whatsoever on it. It is a fabric canvas, is it ok to varnish unpainted canvas?
      Mmm, it’s a tricky one because most varnishes are designed to be removable so you can replace and re-apply them in the future but this will be much harder to do with the raw canvas because the varnish will go into the weave of the canvas.

      Cheers,
      Will

  35. Dear Will

    Great reading, have just bought a old oil painting, 1954, by an australian painter Lance Solomon. The canvas on board was really dirty and dull.
    Cleaned it carefully with cotton balls using my own saliva, a bit gross but really does the trick. The painting is much better, but I want to still lift it up.
    It has been vanished, I suspect with Damar vanish which was most common in those days, it’s really patchy. Should I use damar again, can I reapply in a re-touch method over this old painting, I usually use gamvar vanish on my paintings but I don’t think I should use it on this old painting.
    Any suggestions
    Best regards Al.

    1. Hi Al, yes, you would be able to able the Damar again to give the same aesthetic but if you usually use Gamvar I would personally go for that because it will have less of a yellowing effect than the Damar.

      Cheers,
      Will

  36. Will Kemp I like you thanks :)

    1. Thanks Scorpion, hope you’re enjoying the lessons.
      Will

  37. Hi, this may sound like an strange question, but I’m new to oil painting. Is it advised to varnish the mount or mat board used in the framing as well? Someone told me that they can discolour otherwise, as usually with oils there is no glass on the frame.

    1. Hi Susan, you wouldn’t need to varnish the mountboard, just look for an archival mountboard that is acid free.
      Cheers,
      Will

  38. Thankyou so much, it’s so helpful!
    But I have a question, I just want to protect my oil painting without changing it colors, so I don’t want my painting become matte or glossy, so what I have to do?

    1. You can use a satin varnish, or mix your own between matte and gloss to get the perfect sheen you’re after.
      Cheers,
      Will

  39. Will, wonderful once again, thank you so much for helping me clear this varnishing issue up! God bless!

    1. Thanks Denny, hope the varnishing goes well.
      Will

  40. I want to protect a 20 yr old oil painting that has never been varnished. It is on board with mixed types of paper scrumpled and glued to it. The whole surface is covered in oil paints. As varnishes can go yellow and would need removing (tricky on a surface like this) I wonder if it would be better to use an isolation coat instead of varnish – assuming isolation coats don’t yellow. I’d rather not put it behind glass, unless that is really the best solution. Any tips? And thanks for the great website. I love it.

    1. Hi there, an isolation coat is designed for acrylic paints and wouldn’t be suitable for oils, many of the modern varnishes have less chance of yellowing in comparison to traditional dammar varnish.
      Cheers,
      Will

      1. Thanks for speedy reply. I’ve gone ahead and varnished with a modern one and it looks great.

        1. Good one Sheila, really pleased it turned out well.
          Will

  41. I was taught a while ago to add Re-touch varnish after the oil painting was touch dry for commissioned and other paintings that I sell. I kept some of the paintings and noticed that it lasts about a year before the painting starts to look dried out in spots. I then varnished them and they came out fine. But, the paintings that were sold, I can’t varnish now. Is there a better way to seal an oil painting after it is dry to the touch that will last?

    1. Hi Mark, yes, you can use the Gamvar varnish mentioned in the article, which can be applied when the oil painting is touch-dry. Gamblin have also just recently released a satin and matte version of the Gamvar varnish.
      Hope this helps,

      Cheers,
      Will

      1. Thank you. Great website! I also thought Oiling-out may be useful, but will that dry out too after a year or so? Another question is the Cold wax method–can that be applied to a touch dry painting as a mat varnish and will that last over time giving the oil time to dry unhindered and not damage the oil painting in the long term. Thank you. Love your site!!!

  42. I’ve recently bought a very fine realist painting from a friend. It is oil on board. He finished it with a very high gloss using ,krylon gallery series quick dry varnish. It is too reflective for our house. Can’t see the painting! Can I spray over it with a matte or satin varnish to knock down the sheen a bit? Would you recommend a brand? Thanks. Ann

    1. Hi Ann, yes, you can overspray with a matte or satin varnish, just make sure you really shake the can. Any reputable brand like Winsor & Newton, Golden or Liquitex will work well.
      Cheers,
      Will

  43. Hi Will,
    I have a question. I have used a matt varnish from Michael Harding and I did not like the effect. I would like to revarnish with a gloss varnish. Can I remove it or varnish over it with a gloss varnish?

    1. Hi Jody, if it’s a thin layer you could varnish over the top, but you might still get some diffusion to the darks from the underlying matt. Try to do a small test piece to replicate the matt varnish and then paint over gloss first on a dark background before committing to the whole painting. Michael Harding would be able to advise specifics from his contact page for removing and revarnishing.

      Cheers,
      Will

  44. ☑ A bouquet of thank you for the wonderful information

    1. Cheers Hussein, really pleased you’ve been enjoying the site.
      Will

  45. Although the information on this site was extremely helpful,so far, I can find no one to answer the question concerning alkyd mediums and the use of varnish. Does the type of medium determine the type of varnish you can use? For example, if I use Liquin for a medium, I found that retouch varnish will bead off, and I assume that the final varnish will do the same. I have used this technique intentionally for effect sometimes, but do I need to stick with the oil mediums if I am wanting to use Gamsol or Damar? And what DO I use as a final varnish if I use Liquin or other alkyd mediums, gel or liquid?

    1. Hi Glenda, you can use the same varnishes for oil paintings containing alykd mediums as you would with traditional oils. I tend to favour Gamvar from Gamblin at the moment as it can be applied when the oil painting is touch dry, rather than waiting the traditional 6-12 months before final varnishing.
      Hope this helps,

      Cheers,
      Will

  46. Great Q & A help…Thanx to you & artists!

  47. I use spray on removable dammer varnish on my oil paintings. Couple of them I like to add more highlight. Can I remove where I wanted to touch up? Or I have to remove the whole thing? Can I use turpenoid instead of turpentine? Thank you.

    1. Hi Shirley, yes, you can spot remove areas, turpenoid won’t be a strong enough to dissolve the Dammar resin. I’d try a sample on a small test canvas first so you’ve got your technique down first before committing to the piece you’re working on.
      Cheers,
      Will

  48. Hi will… I am planning to start a work , oils with Liquin. I also have access to ample sun light, to let the work get dried. When would you advise me to varnish the work? How many days gap? I see the paints touch dry in a couple of days. … Please advise and thanks in advance…

    1. Hi Archana, by using the Gamblin Gamvar varnish (demonstrated in the video in the article) it can be applied to oil paints when they are touch dry.
      Cheers,
      Will

  49. Will, Thank you so much for the response. Would you not advise the sane for Winsor & Newton gloss varnish???

    1. Hi Archana, you could use the Winsor and Newton varnish but would need to wait much longer before applying.
      Cheers,
      Will

  50. I don’t leave comments on articles like these normally, but I feel deeply compelled to extend a HUGE thank you to you for compiling such a wise and extensive fact-based article on something that is critical for a professional closure to my oil paintings before they are handed off to my collectors. Thank you. Your thoughts are helpful and the most well-thought-out I have come across after 100’s of ridiculously crafted writing from other “pros”. I will continue look to your page for all future referencing. Blessings to you and your work. Susan

    1. Good one Susan, pleased you found it helpful.
      Will

  51. Hello. I would like your advice. I’m currently painting a series of plein air urban night scenes. I use Langridge Impasto medium and Art Spectrum paints to achieve a thick, stable surface. The problem I’m now having is that the the darks are drying far too glossy. I was wondering if there is matte or lessy glossy retouch varnish out there I could apply, which allows the paint to continue to cure over the next year or two. I’ve used Lagridge and Art Spectrum retouch in the past – both too glossy for my desired result. Otherwise is there something I could mix into the paint?

    1. Hi Dylan,
      Nice to hear from you, have you tried a Cold Wax Medium? Gamblin makes a nice one, you can mix it with your oils and it will make them thicker and stiffer and also more matte. Because you’re adding a matting medium the blacks won’t be as intense and deep but could be worth a try for the effect you’re after.

      Cheers,
      Will

  52. I just discovered your interesting and informative website. However I’m having trouble achieving a non-glossy final finish to my oil paintings and didn’t find a simple solution. I use Liquin as a medium while painting with knife on triple gessoed stretched canvas. Some colours dry glossy and others dull so I tried Winsor & Newton retouching varnish hoping to achieve uniformity. However the finish came out too glossy with some remaining dull spots and a lot of distracting reflections off the texture & impasto. I wonder if adding some percentage cold wax to the medium and/or retouching varnish would solve that problem by sticking to the glossy surface and achieve a satiny overall final result. Would a better result be achievable in the future by switching mediums and using a matte or satin retouching or final varnish?

    1. Hi Peter, nice to hear from you and glad you’ve been enjoying the site.

      For a satin finish have you had a look at the Gamvar new varnishes? They have recently released a satin and matte version.
      Gamvar is a modern synthetic varnish that can be painted over an oil painting when its touch dry rather than waiting 6-12 months as with traditional varnishes and I find it works really well.
      Hope this helps,

      Cheers,
      Will

  53. Hi Will,

    Thanks for all the tips. I’ve just finished what is only my second ever oil painting, the first some time ago at 2ndry school where things like varnishing weren’t left to us… I was just wondering, there are a few small areas on my canvas where I’ve actually left the canvas blank (it’s peeking through the paint to give the effect of reflection on the water and is very much part of the composition). I’m a little scared to put anything on it, in case it soaks into these areas and changes colour or affects it in some way. Do you think this would be a problem?

    Thanks in advance,

    Kathy

    1. Hi Kathy, yes, the varnish would change the surface appearance of the canvas and is harder to control when leaving blank areas due to the viscosity of the varnish (many varnishes have a self-levelling quality to them) what I would do is experiment on a test piece first to see how the varnish aesthetic looks before committing to your finished piece.
      Hope this helps,

      Cheers,
      Will

      1. Many thanks Will, that seems like a good idea (and a good excuse to do another painting :)

        Kathy

  54. Hi Will,
    I am enjoying all the information you offer-great site! I also benefit from reading the comments and problems of your other readers. I started a comment several days ago but got interrupted. Fortunately, I think I found the answer on another site, but would appreciate your input, too. I need to touch up spots where the paint has come off on a painting I did about 30 or so years ago – I never varnished it – the article said to apply linseed oil (I have to use poppy seed oil because linseed gives me headaches), then to paint in the spots needing paint. Does that sound right to you? The article said it was called “in-painting”. Thanks for all your help. Willy

    1. Hi Willy, yes, that’s right, applying a little oil to the area that you’re going to be painting will bring back the lustre to the whole area so will make it easier to match the fresh colours to the previous painting. Hope it goes well!
      Will

  55. Ack. I’ve applied gamvar satin with awful results. I think I should have oiled out but am unsure what to do after the fact. One set of work is a very thinly painted oil over collaged paper that also has some acrylic painted on it – these are small at 16 x 20″. The absorption has been uneven even after 3 coats of the gamvar. The other paintings are thinly painted oils floating on a gessoed surface. The absorption is terribly uneven even after multiple layers and including over the oil painting part but its especially noticeable over the gesso. I have order the gamvar matte finish hoping that adding that on top of the satin might provide the evening out I need. These pieces are 3 x 4 ft. Do you have other recommendations. I have a show in less than a month and six pieces are in trouble.

    1. Hi Leah, on dear, sorry to hear about your results with the varnishing, did the matte finish help at all? I think it might have been due to the differences in absorption between the collaged paper/gesso/acrylic paint and thin oil paint. Each surface will soak up a varying degree of varnish at a different rate so would often give a different sheen to the finish.

      Will

  56. hHi, i just applied a mastic varnish to my oil painting and it left some very cloudy spots. I’ve ony used Dammar in the past and never had this problem. I’m not sure if it will clear up as it dries or if I need to remove it, which makes me nervous. It’s been an hour and it’s still tacky. Any help is greatly appreciated. Thank you! Tracy

    1. Hi Tracy, you can sometimes get clouding in the mastic varnish was applied in a damp or humid environment, I tend to use Gamvar on my oil paintings
      Will

  57. Hey!! thank you so much for this detailed information..Almost everything you need to learn before varnishing. It makes me nervous while applying the varnish but after reading the blog, I am quite confident. Really helpful for both professionals and beginners. I work with the spray varnishes but after reading this I would like to try the brush medium also. :) Thanks a ton! purnima

  58. I have looked everywhere for information about how to protect my oil paintings from dust while they are drying, and all I find is information on varnishing after it has dried. What type of cloth can I drape over the painting? Or something else? I’m only interested in stopping dust from sticking to it during the drying process. I’d really appreciate Any advice. Thanks

    1. Hi Alison, I tend to (rather unscientifically) just prop the painting facing a wall between layers.
      Cheers,
      Will

  59. Will, The Winsor and Newton varnishes seem to say on their label “For oils only” and another which says “for acrylics”. However I have my back ground made on acrylics and the subject made on oil. Could i still go ahead and use the Winsor and Newton’s varnish for ‘oils’?
    Another question, how long should I wait before i use Winsor & Newton’s varnish, on my oil painting which is neither too thick nor thin…
    One last doubt — I have a portrait done, with acrylic on the background and oil on the subject. The colors are as such perfect and fine to look at. I have not varnished yet. It has been a month or more since they are touch-dry. I have still left them open in the room. So, chances are that minute dust particles might stick on the surface. However i plan to get them framed with glass, in another month or so. Now, would you advise me to varnish the painting or let be it??? Please advise.
    Can I clean the surface with a damp cotton cloth?
    Thank you sooo much, for all the time you take. Thanks much in advance.
    Je vous remercie

    1. Hi Archana, I tend to use Gamvar, which is a modern varnish by Gamblin that can be used on acrylics and oils and used when the oil paint is touch dry. Yes, if the painting isn’t too impasto you can use a damp, lint-free cloth.

      Cheers,
      Will

  60. Yes, Thankyou so much Will.
    Would you advise varnishing the painting, which is to be framed with glass???
    Please advise.
    Thanks again

    1. Hi Archana, it’s a personal preference as the glass will protect the surface, but I tend to always apply a protective varnish.
      Cheers,
      Will

  61. Hi Will,
    Wonderful information! Thank you! I wish I had read all of your info before starting my project. I usually spray Retouch Varnish on my oil paintings and months later, spray a final varnish coat. Since moving etc., I really didn’t have a nice clean ventilated area to spray, so decided to brush Damar Varnish on a 24X30 inch oil painting. I used a gloss, watched various videos etc. and probably should have oiled out first and thinned the varnish. I thought the first coat was applied too thick, even thought I went side to side, but there was unevenness, so I applied a second coat. Ughh! There are no dull voids, but thicker areas and very very shiney. Now I worry about yellowing and/or cracking. Is there anything I can do to thin out the applied varnish?

    1. Hi Verna, pleased you enjoyed it, I can’t think of a way of thinning the Varnish after it’s been applied.
      Will

  62. Thanks for getting back to me Will. I was afraid you would say that. The painting will survive, it’s just really shiny:(

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