How to Varnish an Oil Painting

How to Varnish an Oil Painting

Varnishing and Oil Painting with a large brush that does not shed hair.
Brushing on Gamvar Varnish

After All Your Hard Work, Now You’re Ready

You have worked days and possibly months on a painting, and the thought of varnishing your painting may be a scary proposition if you have never done it before. What if I destroy my piece in the process? It’s a valid concern, but there are countless resources that can help you through because wiping a wet and permanent to semi-permanent material over the top of your work can be concerning. However, with a little care and planning you can do it! The video below shows you how to varnish an Oil Painting

Three Reasons To Varnish an Oil painting

  1. Deepens the darks and brings out the colors. If you use a gloss varnish, your painting will look as it did when the paint was still wet.
  2. Acts as a nonporous barrier between the paint surface and indoor/outdoor pollutants. It also allows the painting to be easily cleaned if needed.
  3. Evens out the way light reflects off the paint film. Have you noticed that some areas of a painting will dry flat and other areas are shiny? This is due to the oil to pigment ratio and the medium(s) you use. Varnish can even out this appearance, wether you choose a satin, gloss or matte varnish.
The surface is uneven in this painting, some areas are shiny, others flat.
Do you see some shiny spots and some matte? The dry paint film is uneven.

Do You have to Varnish a Painting?

It’s not absolutely necessary that you varnish an oil painting. It’s a personal choice, and each artist must weight the pros and cons. Personally, I have chosen to varnish some paintings and left others unvarnished. Why? For me, it’s mainly an aesthetic choice, and I feel that some of my work may change in appearance if varnished.

Which is the Best Varnish?

Different brands and varnishes have differing qualities. What varnish you use also depends on what you are looking for. Therefore, the term “best” is a relative term. However, I have a lot of experience using Gamvar and would recommend trying it. especially if you have never varnished before because it’s less toxic and can be easily removed if you make a mistake. You can easily find it on amazon.

Is Gamlin Gloss varnish the best varnish?
Gamvar is the varnish I use.

Below is a running list of varnishes, and their characteristics. More to come as I update this post. Feel free to add your thoughts, or experiences with varnishing in the comments below! (6/5/2020)

Dammar Varnish: A traditional varnish that dries quickly to a high gloss. It is a resin obtained from the tree family Dipterocarpaceae in India and East Asia. Ventilation required – fumes are toxic, tends to darken with age. Check the price on Amazon.

Re-touching VarnishA temporary varnish, often used during the painting process to unify the look of the paint surface and to help in matching dry colors to the new wet layer. Retouch varnish can be painted over and then reapplied many times. Ventilation required – fumes are toxic.

Gamvar: Made of oderless mineral spirits and hydrocarbon resin. Developed in collaboration with the National Gallery of Art, Gamvar can be easily and safely removed with Gamsol. Virtually no smell. check the price on Amazon ( update: Some artists having issues with Gamvar? )

Conservar Finishing Varnish: A colorless, reversible varnish made from hydrogenated hydrocarbon (Regalrez 1094) resin dissolved in pure, low-aromatic solvent and UV stabilizer. Ventilation required – fumes are toxic.

Synvar – An water-clear, acrylic resin picture varnish for oil and acrylic paintings dries to a gloss finish in less than 30 minutes. Excellent durability and good adhesion. Will not darken with age. Ventilation required – fumes are toxic.

Drying Time

Varnish dries faster than oil paint. For example, the Gamblin line of varnishes I recommend called Gamvar dries between 18-24 hours, and has little to no smell. Therefore, out of an abundance of caution, I suggest waiting 6 – 12 months for your painting to throughly dry before varnishing. This recommendation comes from the Artist’s Handbook by Ralph Mayer. (I highly recommend this book. It’s a great resource if you want a quick reference book in your studio on the almost endless list of artist’s materials, and their archival properties

A great guide book for artist Materials
A guide book For artists materials, uses best practices.

If your painting is not thoroughly dry, you run the risk of cracking while the paint and varnish film dry at different speeds. Besides cracking, a benefit to waiting for you painting to dry fully, is that if you make a mistake, Gamvar can be easily removed with Gamsol, a completely oder-less mineral spirit. (Gamvar varnish can also be removed after the varnish has been dried for years.) Varnishing an oil painting does not need to be a scary proposition, but at least you know you can take it off. Good luck, and if you have any questions or additional comments leave them below!

7 Quick Basic Tips.

Using gamvar to varnish your painting
I recommend using Gamvar
  • Wait 6 months to a year before varnishing an oil painting. That way you are certain the thicker oil layers are dry.
  • I like to use a modern varnish like Gamvar, instead of Dammar varnish.  (Dammar dries slower and reportedly yellows over time, and also contains highly toxic vapors)
  • Make sure you are in a dust free environment.
  • Use a large 2.5″ – 4″ smooth brush that won’t shed hairs while you brush on the varnish.
  • Pour a small amount of varnish onto the painting while it’s flat.
  • As you brush it on, look at the paintings from an angle so you can see if your piece is fully covered.
  • Apply in a thin layer.
  • Leave the painting flat for 18 – 24 hours to let it dry.

Video Demonstration:

A simple and quick example of how I varnish an oil painting. I varnish one of my paintings titled: “Plastic“. 

Items used in the video are:

  • Brush: Liquitex Freestyle 4 inch Varnish and Mural Brush
  • Varnish: Gamvar Gloss Varnish

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