Here's the goal: finish a table-top to a rich, lustrous, hand-rubbed, satin sheen – the kind of finish you want to touch with your fingertips just to make sure it's real. It can be done in a home shop, but it takes a lot of work, and even more patience.
The first step in producing that kind of finish is to get the table-top as smooth as possible. Plane the top flat and smooth.
APPLYING THE FINISH
The table-top is smooth and ready for the finish. Now all you have to do is make one choice … between 100 ways to go.
What follows is just one of those ways. It's the finishing technique we used on the Pembroke and Butler's tables shown in this issue. The basic procedure is to apply stain (if you want to), then several coats of sealer, and finally the varnish.
If the top is made up of boards of slightly different colours, you'll probably want to apply a stain to even things out.
Before proceeding any farther, sweep the shop clean of all sawdust. Then wait a day for the dust to settle before applying the sealer. Set up a finishing area with good ventilation, but free of drafts.
THE SEALER COATS
Both of the tables we finished are walnut. It's usually recommended that you apply a paste filler to open grained woods like walnut. To be honest, I'm not particularly fond of working with paste fillers. They're a mess. Besides, three coats of sanding sealer does the job nicely.
Most sanding sealers are formulated for use with lacquer finishes.
To apply the sanding sealer, I used one of those newfangled foam poly brushes, brushing it on as with any other finish.
As you apply the sanding sealer, watch for drips and runs. If there's a run, dip the brush in some mineral spirits and brush it out.
It will take several hours for the sealer to dry, depending on how thick the coat is, the temperature, and the humidity. When it is dry, use 400-grit silicon carbide paper to sand out the roughness. As you start to sand, you should get a very fine white powder. If, instead, the sealer gums up on the paper, it means it's not dry yet.
Apply another coat of sealer. After this coat is dry, hold the table-top at an angle under a fluorescent light. Look closely at the surface. If you see little pockets (pores), it means the grain isn't filled yet, and one more coat is needed.
VARNISH TOP COAT
When all the grain pores are filled, you can apply the varnish. Before you start, make sure the surface is clean of all dust – go over it thoroughly with a tack rag. The biggest problem with varnish is that it takes so long to dry. In order to dry properly, you require a good environment: room temperature between 70° and 80°, low humidity, good ventilation but no drafts.
During the drying time, the varnish is very susceptible to dust from the air. So, the finishing area must be dust-free. It's best to protect the table-top with a piece of plywood right after you've applied the varnish.
Besides dust, the biggest enemy you have to face is bubbles. Do not shake the can of varnish, stir it gently. Load the brush with varnish (fairly full, but not dripping) and spread it across the grain. Continue until the entire top is covered. Then tip off' any brush marks by pulling the brush with the grain.
This coat of varnish will take forever to dry. Allow at least a day, maybe more. Test it by pressing your thumb on the surface. If a thumbprint appears in the finish, it's not dry.
Before applying the second coat, the surface must be sanded smooth. Again, use 400-grit silicon carbide paper. Be very careful not to sand through the varnish, just take out the bumps.
HAND RUBBING
After the final coat of varnish is dry, the surface will probably look quite glossy, but uneven with some bumps of dust particles. What you want, of course, is a smooth, hand-rubbed satin sheen.
To get a hand rubbed finish you need three things: pumice stone, rubbing oil and a felt pad. Pumice stone is a very fine abrasive powder. It used to be available in a range of grits, but now is usually sold in one grit only: "FF" the medium grit.
Rubbing oil is a light oil that suspends the pumice stone, so it can be worked over the surface of the finish.
Soak the felt pad with some rubbing oil. Pour a little pumice stone in a small pan and dip the felt pad into it, or pour a little oil on the surface and sprinkle the pumice stone on top. Then start rubbing.
Rub with the grain in long, even strokes. Don't try to overdo it, just rub with medium press until you feel the pumice stone start to cut. The more you rub, the shinier the finish becomes. (You don't want to rub too much, or you'll go through the varnish.)
Every once in a while, clean off the oil and pumice with a soft cloth to see what you've got. You can stop whenever you get the sheen you want. If you want more of a shine, switch to rottenstone and go through the same process.
When you're done, wipe off all the oil and abrasive powder. There will be a thin layer of oil left on the surface; it will dry out in a day or so. You can buff the top with a Jamb's wool pad and leave it that way, or apply a paste wax. Finally, run your fingertips across the top, just to make sure it's real.
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