Correct buffing technique makes all the difference in woodworking

Using a random orbit sander, work over the whole area evenly and slowly in a grid pattern. A bright light reflecting off the surface at a shallow angle is the best way to highlight areas that need more work.

Building custom furniture was one of the things I did to pay my way through York University back in the early 1980s, and the challenge of satisfying clients pushed me to learn things I probably wouldn't have discovered otherwise. And finishing is where I made some of my most exciting discoveries because that's where my skills were the weakest.

I know it's true that finishing is where many home woodworkers and do-it-yourselfers get disappointed. But disappointment isn't inevitable when you understand one little secret behind successful finishing. Mild abrasion after the last coats of finish are dry is key.

This is why the tradition of hand rubbing evolved, though today there's a much easier option. A few minutes work with a random orbit sander is all that's needed to bring many hand-applied wood finishes up to, and even beyond, professional standards. The trick is a little-known technique called power buffing.

You can power-buff all kinds of finishes, but the details I'll show you here apply especially to urethane coatings, either oil-based or waterbased. The first thing to understand is the need to start with a thick finish-film to ensure that you don't buff right through to bare wood. And this is why four coats of urethane is a good starting point. Sand lightly with 240-grit sandpaper between coats, then let the last one dry for at least 24 hours.

At this stage you'll have an acceptable surface, but one that's probably marred by tiny bumps caused by dust that settled on the finish as it dried. And leveling is the pre-buffing step required to move beyond this problem.

Start with an old piece of the 240-grit sandpaper you used to sand between coats, then wrap it around a block of Styrofoam and rub the wood surface lightly in the same direction as the grain. It only takes a few strokes to remove the dust bumps. Don't use fresh sandpaper for the job because it cuts too aggressively. The surface feels noticeably smoother right after de-bumping, though the surface sheen will be irregular - dull where the sandpaper did most of its work, and shinier where it did less. This is just what you want.

Now it's time to power buff. Grab a random orbit sander and a piece of superfine 3M rubbing pad. This is a thick, non-woven, synthetic abrasive material available at woodworking outlets and better hardware stores. It comes in different abrasive ratings, and the superfine type is what you need. Cut a 6-inch x 6-inch piece, place it on your project, then put your sander on top. Switch on. As the vibrations and rotations of the machine are transmitted to the pad and the wood, it buffs the surface, removing tiny imperfections while leveling out the sheen. Work over the whole area evenly and slowly in a grid pattern. A bright light reflecting off the surface at a shallow angle is the best way to highlight areas that need more work.

You can't get a sander into every nook and cranny, and that's why you should prefinish parts as often as possible before assembly. You can also extend the reach of the buffing treatment using the rubbing pad by hand. Finish up with a coat of paste wax.