Smithy Midas 1220 LTD - Manual (Page 73)

After turning the work to be threaded to the outside diameter of the thread and setting
the gears for the desired thread, put a threading tool in the toolpost.
Set it exactly on the dead center of the workpiece you'll be threading.
To make sure your cutter is on dead center, place a credit card or shim between the
cutter point and workpiece (Figure 16.1). When the tool is on dead center, the credit card
or shim will remain vertical. With a credit card, there is no possibility of chipping the
cutter as the workpiece and cutter come together.
Figure 16.1 Check dead center with a credit card.
Set the compound perpendicular to the line of centers and rotate it 29-1/2° to the right .
Figure 16.2 With the compound perpendicular to the line of centers,
rotate it 29.5 degrees to the right.
Place the thread gauge on the point of the threading tool and feed the tool toward the
work-piece (Figure 16.3). Adjust the tool so the edge of the gauge is exactly parallel to
the workpiece. A slip of white paper held below the gauge will help check the parallel of
the gauge to the shaft and the fit of the toolpoint in the V of the gauge. Placing the
threading tool perpendicular to the surface of the workpiece assures a true-form thread.
16: Cutting Threads on your MI-1220 LTD
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