How to Make Wood Smooth With Varnish

Sand the wood with a fine-grit sandpaper to remove all old varnish, oil and loose debris. It’s critical to sand the wood completely smooth before applying any varnish. Sand down any knots, dings or irregular textures. Sand in one direction and always with the grain of the wood. Be sure to wear safety goggles and a particle mask.

Apply wood filler with a putty knife over and into any fissures or cracks that are present in the wood surface. Sand with the fine-grit sandpaper when dry.

Saturate a cotton rag with denatured alcohol to de-gloss the sanded wood surface and remove residual dust particles or other debris. Let it sit overnight or until thoroughly dry. You can also use a de-glosser, though most de-glossing products have volatile fumes that can be difficult to work around.

Paint the varnish onto the wood using a good quality paintbrush. Apply in thin layers, in one direction, with the grain of the wood. Never go against the grain. Be sure the brush you purchase for this project is labeled for varnishing. For smaller projects use a 2-inch brush and a 4-inch one for larger projects. Let the first layer of varnish dry completely. Check the manufacturer’s instructions for drying time. Some varnishes contain chemicals that speed up the drying process, but as a rule leave it to dry overnight.

Sand the dry varnished surface with steel wool in order to remove the shine from the varnished surface. Do not over-sand -- do just enough to dull the surface slightly. There should be no shine when you’re finished with this step.

Wipe the surface down again with denatured alcohol to remove dust particles. Let it dry completely.

Paint a second coat of varnish onto the clean surface in the same manner described in step 4. Leave it to dry overnight.

Sand the dry varnished surface again with the steel wool, as in step 5.

Wipe the surface again with the denatured alcohol.

Paint a third coat of varnish onto the clean surface.

Rub down the varnished surface with a plain brown paper bag. Use it as though it were sandpaper. This will give the surface a nice clean shine. Be sure there is no print on the paper bag, as you sometimes see on bags from supermarkets or hardware stores.

Apply a generous coat of wax to the surface using a clean, soft lint-free cloth to give your wood surface a final shine. Apply the wax in one direction, with the grain of the wood. Minwax is ideal for this, but any furniture wax will suffice.