I think I will go back to mahogany [wood, as layer for his paintings], the only stable wood, together with old oak. But mahogany is so heavy. And it has another drawback, it blackens even through the primers if they are not thick enough and applied in several coats.
Notes from Wikiquote
Eighty percent of Boudin's beach scenes are painted on wood panels; in small formats, c. 30 x 45 cm