Starting the BowlMark the center points of the maple blank (figure A) and line it up between the head and tail stocks of the lathe (figure B). It doesn't have to be perfectly centered, but it is very important that the speed of the lathe match the diameter of the piece, because the larger the piece gets, the more surface speed it gets. Basically, the bigger it gets, the slower the lathe should be going. To ensure a safe speed, follow the formula of: diameter of the piece x RPMs=6,000 to 9,000. Example: If you are turning an 8" bowl at 1,000 RPMs, it is 8 x 1,000=8,000, within the range of the formula for safe speed.
Place the maple blank in the lathe so you will be turning with the wood grain (figure C), which produces a much smoother, finished project, which will require less sanding. You can determine how the grain is running by looking to see where the bark is on the blank. In nature, tree bark grows up and down; therefore the wood grain is up and down.Tip: Maple is a good choice for making bowls, because it is readily available, but you can also use fruitwood or any hardwood for bowl making. As you start to turn the wood, keep your left hand on the tool. The starting lathe speed here is 700 RPMs. If the tool starts to bounce, use your right hand to press down against the tool on the tool rest -- this will stabilize the tool(figure D). Use very little pressure on the tool, but direct the handle to make it go where you want it to.
All wood cutting tools are made with a bevel, which is a kind of ridge, and the tip of the bevel is the woodcutting surface of the tool (figure E). The trick is to keep the bevel in contact with the wood while you turn, but you don't do that with just your hands and arms -- you work close to the wood with the tool against the side of your body for firm control (figure F). If you hold your arms out and move as you turn the wood, it tends to move the handle. If you move with your legs, with the tool firmly against your side, you have better control.
Cut a tenon, or ridge, along the bottom of the bowl (figure G), where the chuck, a type of vice, will grip the bowl as it is hollowed out of the wood block.The tool hollows out as much as possible of the exterior part of the bowl close to the tail stock, then the bowl is removed from the tail stock, and the center post that has been created is cut out. The bowl is repositioned with the tail stock in place, and the hollowing process continues.Next, turn from the outside in toward the center, making sure the cut is correct with the grain direction (figure H), as the tool cuts down into the bowl, hollowing out the center.
Remove the bowl from the lathe, and sand the outside (figure I), using 100-grit sandpaper first, followed by 150-grit and finishing with 220-grit for a smooth finish.Before the bowl is completely finished, it becomes difficult to keep it held in place on the lathe, so a homemade PVC-pipe attachment is attached to the lathe (figure J). Leather strips are attached to the mouth of the attachment so it will hold the bowl in place without scratching it.
With the bowl and the PVC attachment in place on the lathe, reposition the tail stock to the base of the bowl (figure K). Now the wood under the base can be cleaned up. Use the parting tool to come in close to the tail stock where it holds the wood, removing all excess wood down to the small piece that holds the bowl to the tail stock (figure L). A concave base is made for this bowl rather than a flat base, since the wood is wet. A flat base, when dry, could develop a bulge and cause a wobble.Remove the bowl from the lathe and pop off the remaining piece of wood that held the bowl to the lathe.Finish with an oil varnish. It will make the bowl food safe and enhance the beautiful qualities of the wood.
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