Popular Woodworking 2008-04 № 168, страница 77

Underneath. The jack plane leaves slight but visble scallops; unseen surfaces on quality pieces, such as the bottom of this 19th-century drawer, were left with the jack's surface. This can be useful in helping to identify authentic antiques.

Sight lines. Winding sticks can be used to confirm if a board is flat — or to help identify high spots.

collector clientele should understand, as this clientele recognizes these details. I do the same, leaving the jack-plane track on all unseen surfaces. The bottom of the seat of each of my Windsor chairs always has jack-plane tracks.

Whereas the scrub is used with a short, quick stroke at an angle across the surface, the jack is pushed along the board's face. If the board is short, this can be done with the shoulders, but on a longer board, the plane must be walked.

Smooth Plane

A smooth plane is used for the task its name implies. It is the plane that completes the process of stock preparation by smoothing its visible , wide surfaces. A board off the smooth plane is ready to be worked - to be cut into smaller pieces or joined. Because it too is used on the surface of boards, its cutter is also crested. However, this cresting borders on imperceptible. It is best seen by comparing the cutting edge to a straightedge. The smooth plane will also leave

Almost imperceptible. A smooth plane has such a slight crest on the cutter that it's almost imperceptible, even with a straightedge held against it. This plane leaves a surface smooth to the touch.

a track, but its subtle undulations can easily be removed by sanding or scraping.

Even if you do all your stock preparation with machines, I recommend handplaning all visible surfaces. Jointers and planers work by slicing away narrow, closely spaced scallops. These scallops will show up under a finish. I am proud of my ability to use hand tools and I will unapologetically leave the subtle evidence of my smooth plane. While I use woodworking machines all the time, there is no pride involved, as I do not get any better results than anyone else using the same machine. Thus, I plane away machine marks.

A smooth plane will also clean up the tears in a surface that result from planing against the grain with the j ack. As I noted, few boards are so perfect the grain does not change direction somewhere along their length. In fact, the patterns created by changes in grain direction are what makes wood interesting to look at. It is what causes the curl in curly maple and the flame in flame birch. There is nothing more bland than a board of straight-grained pine, basswood or yellow poplar.

For cleaning up problem areas I maintain a Stanley Bed Rock 604 that is sharpened and tuned so it is a precision instrument. It will handle most problems caused by changes in grain direction. However, there are situations where other techniques are helpful. As a tree grows, numerous things can occur that will give a woodworker fits. Lower limbs die and break off, or the tree experiences an injury. Later layers of growth cover this area, and on the tree this healing will eventually appear as a bump or swelling. If the tree grows long enough, the bump becomes covered by enough layers of growth that it smoothes out and may not even be visible in the bark. How

ever, it did not disappear inside. The layers of growth still have an undulation in them. As the tree is sawn into lumber the saw passes through this swelling, and what remains of it ends up in the middle of a board. It will appear as a whorl, or a cat's face. If you buy the board, the results of the tree's healing become your problem.

The grain will change directions either in the middle or on the edges of the cat's face. Your plane will typically cause it to tear on one side or the other. The solution is to determine whether the grain in the surface you are planing is concave or convex. It will be one way on one side, and the other on the opposite surface. Use the touch-and-go technique. If the cat's face is convex, you need to plane toward the center from one side. As the cutting edge approaches the center, lift the plane to sever the chip. Do the same from the other side. By overlapping the strokes in the middle of a convex cat's face, you can avoid tear-out.

If the cat's face is concave, you do the opposite. Start planing in the center toward the edges of the cat's face.

Knots are another problem. Each knot is individual and you need to observe where the surface is tearing and reverse your stroke. If none of these other techniques work, sometimes it helps to plane at a slight angle to the blemish. Note, the strokes used around cat's faces, knots or other tricky areas are usually very short. Also, no matter what you do, sometimes a scraper and sandpaper are the only answer. PW

A chairmaker since 1971, Michael is the founder of The Windsor Institute in Hampton, N.H., where he teaches hundreds of students each year to build Windsor chairs. Visit thewindsorinstitute.com for more information and

to read his blog.

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