OPTIMUM
M A S C H I N E N - G E R M A N Y
Operation
Version 1.0.1 dated 2015-05-27
Page 58
Original operating instructions
TU3008 | TU3008V
GB
As for thread cutting there are other conditions as for longitudinal turning, the forward cutter
must show a larger clearance as the pitch angle of the thread.
4.18.4 Examples for thread cutting
As an example, a metric external thread M30 x 1.0 mm made of brass is being machined.
Steel sheets are to be laid under the complete tool holder or turning tool to achieve exactly
the turning center.
The lowest spindle speed is set so that the lathe will not coast too long !
Mount gear pairing for pitch 1.0 mm in the change gear !
Img.4-40:
Pitch angle
Pitch angle
Pitch
P
Co
re diameter
Flank diamet
er
Thr
ead diameter
tan
P
D
2
-----------------
=
Abb.4-41: Thread cutting
The outer diameter had been turned to 30.0 mm and the
tool holder is clamped in the quadruple holder for thread-
ing aligned angular to the rotation axis. The height of cen-
tres is checked (as described).
Abb.4-42: radial infeed
The depth of thread is manufactured in
various passes. The infeed is to be
reduced after each pass.
The first pass takes place with a cutting
force depth of
0.1 - 0.15 mm
For the last pass the infeed shall not be
below 0.04 mm.
For pitches up to 1.5 mm the infeed may
be radial.
For our example 5 to 7 passes are being
determined.
