Page:Practical Treatise on Milling and Milling Machines.djvu/144

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Heavy Gang Milling of Milling Machine Tables on a No. 5 B Heavy Plain Milling Machine

The job shown above is that of milling the cast iron tables of small milling machines, and it is an interesting example, illustrative of the economy of gang milling. The top of one table and the bottom of another are milled simultaneously. The castings are held in a special fixture, and when one cut is taken, the piece at the left is removed, the one on the right turned over so that the ways on the bottom can be cut, and a new casting is put on the right-hand side of the fixture.

The table is fed longitudinally from left to right, and the cutters comprise four side milling cutters, one $9 1⁄2$", one $11 1⁄2$", and two $7 7⁄8$" in diameter; five plain milling cutters, two $7 1⁄8$", and three $4 3⁄4$" in diameter; and two slotting cutters, $6 29⁄32$" in diameter.