Sanding and priming the first of two shipments of panels. The first step is inspecting the panels and choosing the best side for the front. I check the joints and corners for damage, or gaps where wood meets wood, and use wood filler to repair.
The next step is wiping the panels with soft cloths to remove shop dust, then the edges of the panel are lightly sanded with 150 grit sandpaper to remove splintery rough spots. Wipe down again.
I use a chip brush to shellac the back side of the panel, preserving the lovely wood grain while sealing the surface.
The front side then receives five thin coats of alkyd primer, applied with a foam brush to minimize brush strokes. When the front is thoroughly dry, I use the 150 grit sandpaper and a block to smooth the front surface to a velvet finish. Wipe down with soft cloths again, ready to start a painting.
Why shellac the back? Is it to keep it from absorbing moisture?
You guessed it. I love the wood grain, so I prefer using shellac to a pigmented primer. The shellac effectively seals the panel.