Can Olive Oil Be Used to Thin Oil Paints?

The age-old debate about using olive oil as a thinning agent for oil paints has sparked considerable discussion among artists. While it is technically possible to use olive oil for this purpose, experts generally recommend against it. This article explores the reasons behind this recommendation and discusses alternative options for achieving the desired consistency in your oil paints.

The Drawbacks of Using Olive Oil

Although olive oil can somewhat modify the consistency of oil paints, it does not dry properly. This can lead to several issues with the paint film over time, such as yellowing or a sticky texture. Moreover, since olive oil is a non-oxidizing oil, it does not undergo the necessary chemical process to solidify, thus preventing the paint from drying.

Commonly Recommended Thinning Oils

Linseed Oil

Linseed oil, a traditional choice for oil paints, is particularly effective in enhancing the gloss and flow of the paint. It works wonders for creating a smooth finish while maintaining the integrity and drying properties of the paint.

Stand Oil

Stand oil is a thicker version of linseed oil that provides a robust, durable paint film. It is excellent for achieving a smooth, polished surface without compromising the quality of the finish.

Solvents: Turpentine or Odorless Mineral Spirits

Both turpentine and odorless mineral spirits are powerful solvents that can effectively thin the paint. These solvents do not alter the drying properties of the paint, making them a reliable choice for achieving the desired consistency.

Why Linseed Oil and Other Oxidizing Oils?

Linseed oil and other oxidizing oils are preferred over olive oil because they undergo the oxidation process. This is the chemical process through which oils solidify over time. Linseed oil, for instance, will thicken and harden when exposed to air, achieving the necessary drying properties. In contrast, olive oil only solidifies under heat, which is not the natural process during the drying of oil paints.

Commercially Available Mediums

Most commercially available painting mediums are variations of oil mixed with varnishes and waxes. However, it is often recommended that artists use just two mediums: gum turpentine and boiled linseed oil. Gum turpentine is suitable for paint mixing, while odorless mineral spirits are best for cleaning brushes.

Another Perspective

It is worth noting the insights from another Quora question about using vegetable oils as a thinner for oil paints. While vegetable oils, such as flaxseed (linseed) and walnut oil, are commonly used in oil paints, they are generally preferred over cooking oils due to their superior drying properties and reduced risk of odors.

Common Vegetable Oils in Oil Paints

Common vegetable oils used in oil paints, listed from the fastest to the slowest drying, include:

Flaxseed (linseed) oil: Fastest drying, strongest film formation, tends to yellow slightly. Walnut oil: Second most preferred, dries less yellow with more fluidity, ideal for fine details and smooth blends. Poppy seed oil: Hides imperfections well but is slower drying. Safflower oil: Fast drying but with minimal yellowing.

These oils share common characteristics like being vegetable oils, drying oils, filtered, and refined to remove impurities like mucilage. Cold-pressed oils are often considered the best for these applications.

In conclusion, while olive oil can be used to thin oil paints, it is not the preferred choice due to the potential issues it may cause. Opting for linseed oil, stand oil, or solvents like turpentine or odorless mineral spirits is generally recommended for better results.