Fig. 1744.
In addition to its value as an adjustable boring tool this device may be used to cut out sweeps and curves, and is especially adapted to cutting those of double eyes. This operation is shown in [Fig. 1744], in which d is the double eye, a is the tool stock, f is the adjusting screw, and c is the cutter. The circular ends of connecting rod strips and other similar work also fall within the province of this tool, and in the case of such work upon rods too long to be revolved this is an important item, as such work has now to be relegated to that slowest and most unhandy of all machine tools, the slotting machine.
It is obvious that any of the ordinary forms of cutter may be used in this stock.
Fig. 1745.
For enlarging a hole for a certain distance the counterbore is employed. [Fig. 1745] represents a counterbore or pin drill, in which the pin is cut like a reamer, so as to ream the hole and insure that the pin shall fit accurately. The sides are left with but little clearance and with a dull edge, so that they will not cut, the cutting edges being at e, c and the clearance on the end faces.
Fig. 1746.