Page:Practical Treatise on Milling and Milling Machines.djvu/108

102 several operations can be performed simultaneously, and with one setting.

It should be kept in mind that in this kind of milling, cutters of the largest diameter, or those that take the heaviest cuts, should, if possible, be used nearest the nose of the spindle, thereby reducing the strain on the arbor. If several of the cutters are plain milling cutters, it is well to use both right-hand and left-hand spirals in order to equalize the end thrust of the arbor. When, in gang milling, the cutters vary considerably in diameter, the inequality of the peripheral speeds may be overcome by having the cutters of large diameter made of high speed steel, and those of small diameter made of the ordinary carbon steel.



Fig. 57