How to Paint Trim That Has Been Varnished
- 1). Sand the trim with 150-grit sandpaper. Sandpaper helps rough-up a varnished surface for easier primer coverage. Sanding can take several hours, but it will help you achieve professional-looking results.
- 2). Wipe away the sandpaper dust using a damp rag.
- 3). Apply protective painter's tape to the wall surfaces and nearby items.
- 4). Prime your trim using a stain-blocking wood primer and a synthetic-bristle paintbrush. Sandpaper helps create good adhesion, but a side-effect of sanding is that you expose the raw wood beneath the varnished exterior. Redwood, cedar, cypress and artificially stained woods will bleed color through primer and paint if you don't use a wood primer labeled as "stain-blocking."
- 5). Paint the trim using a foam paintbrush and gloss or semi-gloss alkyd paint. Glossy paint sheens are more typical of painted trim, but you could use an eggshell or flat-finish alkyd paint if you prefer.
- 6). Peel off the painter's tape after the paint dries.
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