Tim Plate A

Author uses a template to measure circumference and turns the blank until the template fits.

Author checks spherical profile of the top and bottom of die shaker with templates A (above) and C (below).

To delineate the sections of the turning, mark them off with a pencil while the blank is spinning.

well-ventilated space.

Once the glue has set, turn the blank to a cylinder 2% in. in dia. (see top left photo, below), using template A as a guide. (Sec Fig. 3.) Turn the face flat, and while the blank is turning, use a pencil to mark one line '/i in. from the face and a second line \9M in. from the face. (See bottom left photo.) The first line indicates the section of the blank-that will become the stopper, and the second line denotes the center of the sphere you're going to turn.

With the tailstock in place for sup port, turn die stopper and shape it widi a parting tool to the dimensions shown in Fig. 2. Make sure the plug is slightly tapered, so it will make good contact with the hole in the finished shaker.

Now, back off die tailstock and turn a slight undercut on the face of the stopper. (Sec Fig. 2.) Sand and finish, dien part off the stopper and set it aside. You'll finish-turn the bottom surface of the stopper later.

Next, return the tailstock for support and start turning the shaker. Working from the remaining pencil line, use a '¿-in. "superflute" gouge to turn the right side of the cylinder to a hemisphere, again with template A as a guide. (Sec top right photo, below.) To refine the shape, back off the tail-stock and place template A firmly against the spinning wood. This will burnish the high spots, which can then be turned away. When the shape is perfect, the ends of the template will line up with the pencil line. (See top right photo, below.)

With the right side of the sphere finished, drill a '/Wn.-dia. hole in the

Author uses a template to measure circumference and turns the blank until the template fits.

Author checks spherical profile of the top and bottom of die shaker with templates A (above) and C (below).

To delineate the sections of the turning, mark them off with a pencil while the blank is spinning.

blank, using a Jacobs chuck in ihe tail-stock. The hole should be approximately 2 in. deep, but in any case it should stop %i in. short of the glue joint at the base of the turning blank. That leaves enough room to turn a shaker with a !^-in.-thick wall. After drilling the hole, undercut the area surrounding the opening to a depth of lA in. from the rim. (See Fig. 2.) This provides clearance for the stopper. For this cut I use a lMn. gouge with a convex bevel. The convex bevel lets me work a tighter curve than a concave (hollow-ground) bevel would.

Now you can turn the left side of the sphere, using template C as a guide. (See Fig. 3.) Be sure to leave a 1 Vi-in.-dia. supporting stem at the base of the blank. (See bottom right photo, previous page.) Gouges and scrapers are hard to fit between the sphere and the waste material, so I finish-turn this area with shear scraping cuts from the side of a specially ground parting tool. (See photo, top right, and sidebar, opposite page.) When you're done turning, sand and finish the entire sphere.

Now it's time to hollow out the interior. I use several shop-made tools for this work. (See sidebar, opposite page.) Make the initial cuts using the small bent screwdriver tool and working as shown in Fig. 1. Take light cuts at first, and stop the lathe frequently to remove shavings so they don't build up and grab the tool.

Next, use the alien-wrench tool to cut the area closest to the hole as shown in Fig. 1. Then continue cutting and smoothing along the inside wall with the bent screwdriver tool. To finish cutting the center area, where the "nub" forms, use the straight screwdriver tool.

Caution: Using the bent tool to cut the center area in the bottom can be hazardous to the entire process. It has a tendency to skip off the nubble and grab the upward-rotating surface of the wood—blow-up time!

Also, throughout the hollowing process, take care to prevent the shaft of the tools from rubbing against the entrance hole. If the tools touch, they'll not only wear down the hole but cause excessive heat which can crack the wood—especially dense woods such

To work the tight space at the base of the sphere, author makes shear scraping cuts with the side of a h|m*-cially ground parting tool.
Use the tailstock to seat the shaker in the e»mpr<'*Hmn chuck, taking care not to push too hard on the shaker's delicate walls.

as rosewoods, which contain a lot of resin. The shavings also get hot as they're cut, so remember to clear the interior, perhaps as often as each cut.

Measuring wall thickness is quite-simple. Fashion a "loop caliper" (see Fig. 1) from a piece of '/Win.-dia. spring wire or other stiff wire that will retain its shape. Notice how this wire is shaped, with the leg of one end pointing to the tip of the other end.

Positioned one way, it registers wall thickness just inside the lip of the opening. Flipped over, it registers wall thickness near the bottom of the form. If you want a wall thickness of % in., set the gap between the tips to V* in. Touch one tip to the inside wall, and when the gap on the outside measures % in., the wall thickness will also be % in. Pretty high-tech!

After hollowing the inside, fit the stopper to the hole. First make scraping cuts with the straight screwdriver tool until the stopper scats firmly. Take ultra-light cuts, or you may end up having to turn a larger stopper. When the stopper fits, tap it firmly into the hole and finish-turn its bottom to a nice concave profile. (Sec Fig. 2.) When you're through, the rim of the stopper should be below the base of the shaker. Sand and finish.

Finally, pry the stopper out of the hole with a screwdriver and sand the hole lightly until die stopper fits snugly. If all has gone well, the grain of the stopper will be a book-match of the grain on the base of the shaker.

Now, use a parting tool to part the shaker from the waste block, taking care not to cut into the profile of the sphere. Mark the center of this parted-off section with the point of a sharp nail. This will help you center the shaker in the compression chuck. (Sec sidebar, page 38.)_

To finish-turn the top, loosely position the shaker in the compression chuck—stopper side facing inward— and draw the tailstock forward, positioning the point of the live center into the nail hole you just made in the top surface. The shaker is very fragile, so compress it slowly into the chuck using the handwheel on the tailstock. (See photo, center left.) You want a tight fit, but don't overdo it with too much pressure.

Remove the tailstock and check to be sure the sphere is secure. Finish shaping the sphere with a small-tipped scraper or a small gouge, using template B as a guide. Take light cuts to prevent popping the sliaker loose from the chuck. (I often use the fingers of my left hand to add a slight amount of pressure against the shaker while the tool does the cutting.) Sand and finish while the shaker is still on the lathe.

A curved-tip scrufwr made from u cement nail flares the edges of the shaker's holes.

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Wood Working for Amateur Craftsman

Wood Working for Amateur Craftsman

THIS book is one of the series of Handbooks on industrial subjects being published by the Popular Mechanics Company. Like Popular Mechanics Magazine, and like the other books in this series, it is written so you can understand it. The purpose of Popular Mechanics Handbooks is to supply a growing demand for high-class, up-to-date and accurate text-books, suitable for home study as well as for class use, on all mechanical subjects. The textand illustrations, in each instance, have been prepared expressly for this series by well known experts, and revised by the editor of Popular Mechanics.

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