Difference Between Gesso and Molding Paste

Can You Mix in Oils?

Painted Canvas - Primed Landscape
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Question: Is There a Difference Between Gesso and Molding Paste, and Can You Mix in Oils?

"Is there a difference between gesso and molding paste when you want to create some texture on your canvas before you begin an oil painting? Can oil paints be mixed into either of these mediums or is it always applied on top after they dry?" -- Caysha

Answer:

It depends on how much texture you want. You can use a thin coat of gesso to mimic plaster texture.

But going too thick runs the risk of it breaking and flaking later. The more rigid the support, the less likely this is, so consider painting on a canvas covered panel. These are available through most art suppliers.

If you want a more sculptured effect, then modeling gel is better. It is designed for this, while gesso is not. You can mix acrylics into both gesso and modeling gel, but not oil paints; unless you find a modeling gel that specifically says you can mix oils with it, it's best to assume it's water-based.

Modeling gel remains more flexible than gesso does, so there is much less danger of cracking and flaking. Also, you can embed things in the modeling gel, while you cannot with the gesso.