Page:Popular Science Monthly Volume 92.djvu/634

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��Popular Science Montlily

��and the blank is formed up as required.

The inclination of the slant determines the diameter of the rolled part. Even with the small portion of material wasted, the saving of time in making the parts makes this way an improvement on the old method of cutting them from ribbon stock and forming them in two opera- tions. — S. B. Royal.

A Wood Mold for Casting Minia- ture Car Wheels

TO make a number of cars with which to equip a miniature railway, many wheels just alike will be required. To cast these from metals of low melting temperatures in sand molds, it is necessary to make a great many of them. If care is not taken they will come out rough and will need more work to prepare them for use on the cars. The mold illus- trated is one that can be used over and over again. It makes castings all alike and turns them out nicely finished, ready to assemble. The mold is turned in a close-grained piece of hardwood; in the end grain. Two pieces are necessary and the drag or bottom part should be turned with a ledge, and the cope or upper part should be turned to fit in it as shown at the parting line. These surfaces, when turned at the same time that the mold is made, will cause a perfect match- ing of the parts for each pouring of the metal.

The gate should be turned tapering so that the larger part will be at the casting. This will make it easy for the piece to be removed when it cools. Spokes may be formed by placing small blocks, cut to the right shafje, in the web of the mold. A number of castings can be quickly made in this mold from babbit metal. As the hole for the hub is made when the

���Mold of wood to cast wheels of babbitt metal

��wheel is cast, it only has to be reamed out in order to fit the axle. The draft given to the mold forms the right skpe to the wheel surface for rolling on the track. — Henry Wedde.

��Compasses Made Into a Combination Drawing Tool

PERSONS who do considerable draw- ing or lettering, sooner or later find the so called railroad pen and railroad pencil an absolute necessity. These are expensive tools, however, and an excellent substitute may be produced cheaply.

Procure two of the compasses such as are here shown and use one pair complete. Pull the points out of the other compass and lay the body away for future use in case of breakage. The points are the only part of the extra pair needed. With

���Making five different com- binations with one compass

the 'se of one pair of compt^sses and the four points, five different com- binations are available. You can have a railroad pen, a railroad pencil, dividers, and pen compass and i)encil compass as shown in the illustrations. V^ery neat work may be done with this instrument. — Albert E. Jones.

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