Taper Boring Procedure; Working Procedure - Narex Vhu 2 1/8" Instruction Manual

If the tool is clamped on the direction of the transverse feed of the tool slide, an expanding
taper will be bored. If the same tool is clamped in the direction opposite to that of the
transverse feed of the tool slide, a narrowing taper will be bored. When clamping the tool, be
sure to set its point in the plane passing through the axes of the holes for rods and holders (7)
– (see Fig. No. 14), otherwise the taper will not be accurate.
c) Taper boring procedure:
1. Clamps the tool according to paragraph b) and by means of the dial for the tool slide quick
traverse (12) and the tool slide fine setting dial (4) set the tool to the initial boring diameter.
2. Advance the spindle so that the tool cutting edge is approx. 0,09 in above the surface of
the workpiece and set the tool slide dial in this position to zero.
3. Withdraw the spindle by a few millimeters and advance to zero by the spindle feed
determined from the chart. Stop the machine when reaching zero, but do not disengage
the feed.
4. Adjust the trip dog according to Fig. No. 13 and tighten.
5. Engage the clutch (15) and screw in completely the clutch adjusting screw (14). Thus the
disengagement of the clutch (15) in case of overloading is excluded. Accordingly,
increased attention is necessary during operation.
6. Insert holding rod (17) into the hole in the braking ring (1) and support it by the positive
stop on the machine.
7. Start the machine. Now tool slide (5) moves simultanously with the moving machine
spindle and forms the required taper.
8. After completation of the job remove the holding rod (17), return the boring head into its
original position and cut another chip by means of the trip dog (10) and gauge or dial (4).
This procedure will be repeated as required. External tapers can be machined by a similar
method.
IV. Thread cutting
The braking ring (1) must be caught when cutting threads as this could cause an axial motion of
the tool slide (5).

Working procedure:

1. Mount the tool.
2. Engage the respective feed corresponding to the head of the thread.
3. Traverse the tool slide by means of the dial for quick traverse of the tool slide (12) and cut
the chip by means of the dial for fine setting of the tool slide (4).
4. Start machine, cut the thread and stop the machine.
5. Withdraw the tool by means of the dial (12) or dial (4).
6. Cut another chip and repeat the whole procedure as required.
Fig.14
9