Polyurethane is the contemporary product most frequently used as varnish, or clear conclusion, on painted and stained wood surfaces. To reach the highest degree of gloss, and to make the smoothest possible finish, wet sanding every coat of polyurethane is the favored method. It’s imperative polyurethane be allowed to cure thoroughly before wet sanding to get the best results.
To make a quality, high-gloss, lacquer-style finish, you have to begin with the smoothest potential wood surface. In addition to filling any voids using traditional wood filler, a wood filler paste could be used to smooth the grain of this wood. Sand the wood down to as fine a surface as possible, using a power sander or sandpaper and functioning from 200-grit around 320-grit sandpaper before applying stain and polyurethane. Scrub the surface with a tack cloth after the final sanding to remove any fine dust that may become trapped in the end.
To get the end you need, select the proper gloss. In most instances where wet sanding is involved, a high gloss finish is intended. Select polyurethane using a gloss or semigloss sheen. Horizontal and matte sheens cannot be made to accomplish a high gloss finish because of dulling agents that are a part of the formula. High gloss urethanes are also typically harder than duller finishes. You’ll need to use a separate stain and clear finish to reach the best results possible.
Permit your stain to heal overnight before applying the first coat of polyurethane. Utilize a medium-width soft bristle brush. Function in long, directly overlapping strokes, keeping the brush moist to minimize brush marks. Cover the entire surface, functioning to prevent runs and drips. Permit the end to harden overnight. Pour 1/2 inch of water into a skillet and add 2 drops of detergent to break the surface tension, allowing the water to boil. Put a rubber sanding block using 320-grit wet/dry sandpaper on it to the pan. Apply water into the surface of the polyurethane and sand, working in a circular pattern. Scrub the surface with a clean cloth every so often to gauge progress. Work until the surface has an equivalent dull haze to it.
Apply the second coat using a similar technique to the first. Let it set overnight, then sand in precisely the same way as the first coat. Wipe the surface clean using a damp rag and allow it to dry. Examine the surface to make certain it is evenly sanded; resand as needed. Apply a coat of car wax to the surface as a finishing touch to bring the gloss up to its greatest level. Use a sponge to use it moist in a circular motion. Allow it to dry until fuzzy, then buff to high glow with a soft, lint-free rag.