Centering

To ready the wood for the lathe, we first find the centers. Split the billet to keep the grain intact for strength and shave it close to size. Shaving a leg can mean roughly rounding it with a drawknife, or it might mean shaving it with planes to a square section for joining to the rails of a chair or table. In square-sectioned pieces, you can find the centers by drawing diagonals connecting the corners. You can find the center on any shape by repeated strokes with a marking gauge or dividers set at approximately half the thickness. Worked from all around the outside, the mesh of lines will bound the center.

Lathes also have centers. Treadle and great-wheel lathes (and others) have head stocks that support the drive center—a bladed spike that sticks into the wood to turn it. The other end of the wood spins on a polished, perfectly conical point—the dead center, mounted in the moveable tail stock. A spring-pole lathe usually drives the wood directly by a cord wrapped around it, so it uses two dead centers.

The lathe centers engage the centers of the wood, and a little preparation on the wood end helps them do that better. I always saw the slots for the drive center of the treadle lathe. On the dead center end, I either make a small depression with the point of the skew chisel or, in critical work, I drill a shallow hole with a small bit. A stroke of wax or grease to the dead center hole ensures easy and quiet turning.

The centers let the wood spin, but, at the same time, constrain it from wobbling or flying off. In metal lathes, you use a screw on the dead center (or ball-bearing live center) to adjust the amount of pinch given the wood. Wooden-bodied lathes may also have screws, but they work as well or better when treated like wooden planes. A tap at the base of the wooden tail stock moves its dead center in, and the wooden bed of the lathe flexes slightly, keeping the work piece tight yet free spinning.

Once in the lathe, there's a series of slow speed checks before the real turning begins. If the piece is curved in its length—centered on the ends but whipping around in the middle — you may have to reset at different centers to make a better compromise. The slow-speed turning also gives the centers a chance to set in. The tail stock usually needs a little more adjusting as you find the right amount of pinch.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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