Oil Painting on Wood: Selecting Wood, Protecting Grain, and Building Better Grounds

Oil painting on wood requires careful preparation because wood expands and contracts with humidity and wicks the binder into its pores. This article reviews a short paper by Anne‑Marie Olsson and Dick Sandberg on how wood and high‑solid linseed oil paint interact. It translates Olsson and Sandberg’s measurements into studio practice: why dispersive forces—not chemical fusion—govern adhesion; how capillarity causes early sink‑in; and why hardwood panels outperform softwoods. You’ll learn to select stable hardwood substrates, seal face, edge, and end grain (front and back), and lay an oil ground that limits binder loss and moisture‑driven damage.

How the study was done

The authors measured contact angles of probe liquids placed on linseed oil films on glass and on Scots pine, before and after drying. They used water, formamide, ethylene glycol, and diiodomethane, and applied a Young–Dupré acid–base model to split the surface energy into dispersive and polar components. In their terms, “high‑solid” paint is linseed‑oil paint with minimal solvent that dries by oxidation. These measurements frame adhesion behavior relevant to oil painting on wood.

What the study found

Apolar forces dominate adhesion

Wood and linseed oil share a strong dispersive component and only a small polar part. Water is different; it has low dispersive energy and strong polarity. Therefore, water can disrupt the small polar part of oil–wood adhesion but not the larger dispersive part. This balance supports stable adhesion for oil painting on wood.

Work of adhesion: oil–wood vs water–wood

The work of adhesion is about 80 mJ/m² for linseed oil on wood and about 120 mJ/m² for water on wood. Oil binds well, even though water binds more strongly in that metric. After curing, dispersive interactions still do most of the work. This is significant for oil painting on wood in variable humidity.

Contact angle behavior reflects penetration into wood

On undried wood, the contact angle of dried oil paint falls quickly over seconds as oil penetrates; on glass, where no penetration occurs, the angle remains steady. After drying, wood and glass values converge. This supports the idea that penetration drives the early change. This matters when planning first coats for oil painting on wood.

Wood structure governs penetration

Whole oil molecules are too large to slip between cellulose chains. However, they move through lumina and pit openings. Therefore, capillary flow in these features controls uptake more than diffusion into the cell wall. Understanding these pathways is central to sizing and priming for oil painting on wood.