The Plane Truth

One day I found myself in the shop facing one of the biggest, prettiest planks of bubinga I'd ever seen. True, it wasn't the most politically correct wood to make into a coffee table, but it was bought before I'd heard of the ozone layer, deforestation, and all the other connections between this board lying on my bench, and the survival of our planet. It had stood for a long time in the stack labled "Someday when I get time." Now I had the time and the idea. But this great expanse of board (1 in. x 20 in. x 66 in.) that was absolutely flat when I had put it away, had taken on annoying curves.

A friend suggested that the only way out was to take it to the machine room and spank it back into shape. I was to rip it into 8-in. widths, run it over the jointer, through the planer, and then edge glue the flat pieces. But how could I disturb that beautiful plane of unbroken grain? That plank wanted to stay together. Who was I to get in the way of so noble a desire?

Despite warnings of the hardships of working bubinga, I set expediency aside, rolled up my sleeves and reached for my roughing plane. This board was special. It had waited too long for me to let this experience slip into the dust collector.

I'll grant you, it was work, but sometimes work feels good. I smelled the fragrance of the wood as the shavings formed in heaps around my ankles. The whole process left me intimately acquainted with every square inch of the board. What could have been done in four or five hours with the help of the power company, took ten hours by hand.

In the end, my body had the satisfying feeling that it had been used for a good purpose. My skills were honed just a little bit sharper. But most important, my spirit had been exercised as well. There was a mark on that piece of furniture, wherever it found a home. It still belongs to me as a craftsman—and not to the machines.

ripped two pieces of plywood to the same width and ran a strip of black electrician's tape down the top edge of one. They worked just fine.

You need the marking gauge to scribe the desired thickness on the edges and ends of the board after you've flattened one face. I prefer to use a steel-pointed gauge. The line is always the same width, and I can get very accurate thicknesses by planing to the center of the incised line.

Diagnosing a Board

If a board isn't flat, it will be cupped across the grain, bowed with the grain, or twisted along its length. Frequently, it's all three at once. (See Fig. 2.)

Cupping and bowing are easy to see. Just sight along the end or edge, or check against a straightedge. (The sole of your plane, held on edge, makes a handy straightedge.) Twists are sometimes not so apparent. Even if both ends are flat and both edges straight, a board can still be twisted. The simplest way to check for twist is to place the piece on a flat surface (your benchtop or tablesaw) and push gently on diagonal corners. If it rocks, it's twisted. Mark the diagonal pair of high corners so you can plane them off.

W'inding sticks come in handy when you need to check a large board that won't fit on your flat bench-top. Place a stick across the grain at each end of the board, then kneel, and sight across the upper edges of the winding sticks, as shown in the photo. If they're out of line, the board is twisted. The misalignment is often very slight (Fig. 2 shows an extreme case), so you'll need to do some careful squinting.

Remedies

You'll save yourself a lot of elbow grease and no small amount of wood if you lay out and cut the stock roughly to the length and width you need before you plane. Why flatten a cupped 12-in. wide board if what you need is two 6-in. wide pieces?

FIG. 4: FLATTENING THE CONCAVE FACE

FIG. 4: FLATTENING THE CONCAVE FACE

STEP t:

Establish flats on outer edges by planing across the board at an angle.

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