WAINSCOTING-109 Part 6: Prepping for Paint

[This is part of our WAINSCOTING-109 Installation series.]

Preparing the Wainscoting for Paint

Moldings rarely get installed perfectly the first time around. Now is the time all those little imperfections or embarrassing mistakes can be taken care of.

All of these preparation steps help you get your moldings to an ever-increasing state of perfection.

These are the steps I follow to prepare moldings for paint:

Spackle nail holes and other small gaps
Sand the spackling
Vacuum the moldings
Wipe down with damp rag
Prime all the moldings with a sandable primer (see our Consumables page)
Sand all of the moldings with fine to medium grit sand paper and sanding sponges
Vacuum the moldings again
Wipe down the moldings again with a damp rag
Re-prime/sand/vacuum/wipe bare spots (see images below)
Caulk all remaining gaps
Apply two finish coats of molding paint

Use a Palm Sander

It’s hard to install the edge detail perfectly flush with the top of the flat-stock rail cap.

So I smear some spackling along the seam, let it dry, and then take my beloved Porter Cable palm sander to it.

The seam between the two main mdf board panels also need sanding. The palm sander made quick work of that too.

Apply the Unifying Coat of Primer

Primer that’s designed for bare wood will dry with a chalky surface.

That surface can be sanded off with a fine grit sandpaper leaving a smooth surface behind.

Start at the top of the wainscoting and work you way down. It’s best to work in sections.

This kind of primer dries fast, so you won’t have to wait too long before you can sand.

The best way to get sanding dust (and cat hair) off of the moldings is to vacuum them.

You can’t sand caulk.

So save caulking for the last step.

I have a few bare sections where I had to sand pretty hard, so they will need to be re-primed and re-sanded and re-vacuumed and re-wiped down with a damp rag, but they are small and not near the caulk.

Paint is reluctant to stick to corners like these if they don’t have primer on them. So make sure they get re-primed if sanding exposes bare material.