How to Use Paste Wood Filler

Sand the project piece with 220 or finer sandpaper by hand, working in line with the grain. Focus on getting the surface as smooth as you can. Rub a tack cloth over the surface to remove any and all dust.

Thin the paste filler with naptha thinner until it is the consistency of heavy whipping cream. Mix the filler thoroughly with a small tongue depressor until the thinner and paste are completely combined.

Dip a coarse synthetic bristle paintbrush into the thinner and spread it over the surface, working across the grain to fill pores and other small imperfections. Follow behind with a stiff, thin scrap of wood, such as a shim, with the end sanded smooth to scrape the filler from the surface surrounding the areas it is filling.

Allow the filler to dry for several hours. Cut a 12-inch square of burlap. Buff the surface of the wood with the burlap to remove thinner from the smooth portions of the wood. Rub across the grain. Shift to a clean patch of burlap about every thirty seconds to prevent re-spreading the paste. Allow the filler to dry for 12 hours and reapply to any area that requires it due to shrinking. Rebuff the surface with a fresh piece of burlap.

Buff a second time with the burlap, this time working with figure eight motions to eliminate any paste you may have dragged onto the surface, which will show in the stain. Sand the surface with 320-grit stearated sandpaper by hand. Work with the grain, focus on buffing the surface to a glow and removing any residue of the paste other than in desired places.