PVA Size?

edited November 2020 in Studio & Supplies
Hello, I have decided to finally make the plunge and sell the majority of my acrylic paint and supplies in order to move fully into the oil medium. I am deciding between buying the roll of centurion oil primed canvas, and buying a roll of claessons fine tooth canvas on sale and priming it myself. I believe PVA to be an adequate size, especially when 2 or 3 coats are applied, but after coming across this article I wanted to reach out to the community and ask specifically about whether PVA size is the commonly used and recommend choice, or if some of you use the GAC 100 primer instead? Also any comments on the quality of claessons “fine” canvas is appreciated (if it helps Ian mainly interested in portraiture and other high realism) Here is a copy of the bit of the article in question, along with a link: https://www.goldenpaints.com/technicalinfo/technicalinfo_prepsupp

Blocking Oil Penetration from Oil Paints

GOLDEN Laboratories conducted a study to find out which medium used as a size would stop oil penetration the best. The results were that two coats of GAC 100 did the best overall, with Fluid Matte Medium also performing well. When using any of these products to block oil penetration, it was found that a minimum of 2 coats was required to adequately block the oil, with additional coats offering additional insurance and protection of the support. A typical Gesso required 3 or more layers to fully prevent the oil from passing through to the support. The reason for this is that the Gesso is designed to be porous and moderately absorbent to facilitate adhesion of subsequent paint layers.

For maximum oil blocking, let dry for a minimum of 3 days before painting.

Stiffening and Blocking Oil

To date, the best system to both stiffen the canvas and block oil penetration is to first apply 1 coat of GAC 400 to the front of the canvas to develop the stiffening of the fabric, followed by 1 coat of GAC 100 to achieve the oil blocking properties. Once dry, apply 2 coats of Gesso to the front.

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