3 reasons to avoid using alkyd mediums like Liquin as an oil painting varnish.

Why Alkyd Mediums are Popular with Oil Painters

Alkyd mediums are popular among oil painters. They can speed up drying time, help the paint flow more easily, and increase or decrease gloss (Liquin causes a satin sheen while Walnut Alkyd Medium increases gloss). They also cause oil paints to dry with a tougher, more durable paint film.

Do not use Liquin to varnish your paintings!

Those last two properties may be why so many artists use alkyd mediums as an oil painting varnish. My recommendation: DON’T use them to varnish oil paintings.

Why NOT use Alkyd Mediums as Varnish?

1. Modern varnishes offer excellent protection from dust and debris and contain UV ray stabilizers. Dust that settles onto unvarnished paintings, including those covered with a layer of alkyd medium, cannot be easily cleaned. The dust may become permanently embedded in the paint/alkyd surface. Also, alkyd mediums like Walnut Alkyd Medium or Liquin do not provide the same level of UV protection as traditional varnishes. UV rays can cause colors to fade and the paint to crack and become brittle over time. 2. Alkyd mediums cannot be removed once they have been applied to the painting. They become a permanent part of the painting. This can make conservation and restoration more difficult. Traditional varnishes can be removed with mild solvents like Gamsol, allowing conservators to clean and restore the painting if necessary.

Gamsol Mineral Spirits image

Gamsol mineral spirits will remove modern oil paint varnish – not alkyd mediums.

3. Alkyd mediums used in excess can darken or yellow severely. Just look at a clear bottle of alkyd medium like Liquin, and you will see that the liquid is a dusky reddish brown. That’s because of the thick, concentrated amount. When you use a small amount in your paint, it will not adversely affect or discolor your painting, but if you apply unnecessary layers of alkyd without pigment added, those layers will darken the painting.

M Graham Walnut alkyd medium, Winsor & Newton Liquin, and Gamblin Solvent-Free Gel medium image.

M Graham Walnut alkyd medium, Winsor & Newton Liquin, and Gamblin Solvent-Free Gel medium

You might disagree – if so, what has been your experience using alkyd as a varnish?

I’ll repeat my recommendation – DO NOT use alkyd mediums like Winsor & Newton’s Liquin, Gamblin’s Solvent-Free Gel, or M Graham’s Walnut Alkyd Medium to varnish your paintings. They are neither designed for nor suitable as a final varnish for oil paintings. While they can be used as additives to improve the properties of the paint, they do not offer the same level of protection and removability as traditional varnishes. Artists should use varnishes (like Gamvar) made specifically for oil paintings to ensure the longevity and quality of their artwork. That being said, maybe you use Liquin or some other alkyd medium to varnish your paintings for a specific aesthetic reason. Maybe you’ve been varnishing your paintings with alkyd medium for decades with outstanding results. Please share your experiences with us in the comments below. One thing I’ve learned from years of studying art and art materials is nobody knows it all – not professional artists, art conservators, or art supply manufacturers. It may turn out that aside from the removability issue, alkyd mediums do a fantastic job of keeping oil paintings damage-free generation after generation. p.s. You can use it as a retouch varnish or to oil out a painting, but don’t cover the entire painting with it. Only use it in those areas you know you will be painting over during that day’s painting session. p.s.p.s. Don’t use traditional retouch varnish either (but that’s for a future blog)! Use a very thin layer of walnut or linseed oil or alkyd medium to freshen up sunken areas, preferably only those areas you will be painting over again.