This section is from the book "Art And Education In Wood-Turning", by William W. Klenke. Also available from Amazon: Art And Education In Wood-Turning.
As with the Indian clubs, there is no special wood used for dumb-bells, Plate V, except that it is necessary to have a hardwood, such as maple, in order that it may stand rough usage. The stock is 3"x3" x10 1/4".

Plate V.
Two methods may be employed with equal success in turning the balls at each end. The first method is similar to that of the Indian clubs, that is, by using a templet cut to a semicircle and resting it on a 1" diameter at either side of the ball. Shape to fit the templet. The second method is by geometry, Fig. 33. Turn to 2 7/8" in diameter and cut to the same length, making the section a perfect square. Lay off an octagon; and so on, increasing the number of sides up to 64 when a sphere has almost been turned. See Croquet Ball.
After the balls have been shaped, turn the handle, sandpaper and polish. The ends are then cut to about 5/16 in diameter. Saw off all waste wood, trim up the ends with a sloyd knife, and finish the same as the Darning Ball.

Fig. 33.
 
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