CHAPTER 14, LESSON 1 of 1
GOAL: To learn the final steps involved in bringing a project to successful completion.
It's been a long journey from design through harvesting the parts, marking up, shaping the parts and finally putting all the pieces together. But two crucial operations remain: cleaning up the final surfaces and applying a finish to protect the fruit of your labor. This lesson explains the virtues of a simple finishing system that requires only a hand plane, sandpaper, shellac and beeswax.
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| Planing the surface of a finished piece poses added problems, not the least being how to hold it. Here the work is perched on a sawhorse (not shown) and then clamped to the bench.
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It's important to keep checking for high and low spots when planing. When using a sanding block, hold the block flat with constant pressure.
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| Apply the shellac quickly. Cover the whole surface, then "lay it off" altogether. Don't do bits at a time. |
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| The surface will feel rough after the shellac dries because of swollen fibers called "nibs." Remove them with very fine worn paper held in your fingers. |
With final assembly completed, you've reached the end stage of furniture making, what those in the British Arts and Crafts tradition call "cleanup and polish." "Cleanup" means making the wood surface ready to receive the finish, and "polish" means applying the finish on the prepared surface. Just as we used the language of the Arts and Crafts movement to describe this step, so this lesson will lay out the traditional Arts and Crafts process for preparing and finishing a project.
Cleanup
Chances are pretty good that most of the wood stock used in your project will have been sized and made square by a jointer, planer or table saw and that, as a result, the stock will bear milling marks left by the cutterheads. Such minor imperfections have major implications at the finishing stage. Just as polish highlights the color and grain pattern of the wood, it also emphasizes all its defects. The challenge is to remove those defects.
To bring the machined surface to a polish-ready state, we will focus on the use of a smoothing plane and, occasionally, abrasives.
Assuming that the workpiece is narrower than the plane width and that the plane is sharp and correctly set, it usually takes four passes to make a machined surface smooth and ready to polish.
There are situations where a surface is improved by sanding — for example, when dealing with tearout or an area, usually around a pin knot, where the grain goes the opposite way to the rest of the board.
To enhance speed and control while sanding, use a cork block with sandpaper wrapped around three sides. Divide the sheet of abrasive paper into six pieces and size the block to permit thumb and finger grip.
Because the finish to be used in this lesson is shellac and beeswax, start with 320-grit sandpaper and go to 400. If the surface is to be painted or a film-building finish such as lacquer is to be applied, it's unnecessary to sand finer than 180-grit.
Polish
Clear shellac serves as a barrier to prevent the beeswax from soaking into the wood. It is best applied with a clean, lint-free cloth. With the rag formed into a pad, spread the shellac in circles quickly and thinly to wet the entire surface at once, then lay it off by wiping in the direction of the grain. Don't apply a second coat: it will dissolve the first coat and make a sticky mess.
You could also brush on the shellac, but a special technique is required because application by brush leaves a heavy deposit and shellac dries too quickly for continuous brushing. Start with a loaded brush and cover the surface quickly, then wipe it off with a dry rag.
The shellac will be dry to the touch in about five minutes, but the surface will have been roughened by swollen fibers called "nibs." When the shellac has dried to the point where it won't immediately gum up the sandpaper—usually after 30 minutes — de-nib the surface using worn 320- or 400-grit paper held in your fingers. Sand to the point where it seems you are removing the shellac coat altogether — you won't. Then remove the dust by vacuum. You can make your own beeswax polish by dissolving one measure of pure granulated bleached beeswax in about five measures of pure turpentine overnight in a container. Its consistency should be like a block of butter just before it loses its shape to melting.
To apply, form a soft, lint-free cloth into a pad and lightly load it by scraping across the wax surface in its container. Rub the pad in circles on the workpiece until you have "rubbed it out" — that is, there's no more free or visible wax. Less wax is better than more. The result should be a surface slightly sticky to the touch. Finish by polishing with the grain, then leave for at least four hours. Then apply a second coat. To heighten the luster, buff the surface without adding more wax.
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