Operating Instructions Thread tapping units/ Accessoriesr 01/09, Software 4.9
©
01.1994-2016 microtap GmbH
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4. DSz
(tolerance on spindle advance)
This is the permissible tolerance on the advance of the tap to contact with the
pilot hole (applies only if option ZAP is installed). For instance, if you enter 0.20,
this means that a tolerance of 0.20 mm is acceptable on the spindle advance.
If the spindle advance is longer or shorter than the set advance by more than
the selected tolerance, the machine does not start.
5.
RPM
(spindle speed)
The spindle speed must be selected accurately to permit threads to be tapped
with a low applied torque.
The thread tapping machine shows the value of the applied torque continuously
on its display. This feature helps you to establish the best spindle speed for any
given job, by carrying out tests at different spindle speeds.
The same test method applies for finding the best lubricant and tool type.
6. DEPTH
(depth of thread)
This value determines the depth of the thread tapped in the workpiece.
7.
CUTR.
(cut relief)
This menu prompt determines how often the spindle should reverse in the
course of tapping operation to break the chip.
Cut relief avoids the jamming of long chips in blind holes. It permits tapping of
blind holes without discernible increase in friction due to difficulties in chip
removal.
Cut relief is recommended only when tapping deep blind holes (of depth greater
than 1.5 times the hole diameter) with spirally fluted taps.
Through-holes are normally tapped with straight-fluted taps. Do not use the cut
relief facility, because due to the large clearance angle at the tap flanks the chip
tends to jam when the tap reverses.
