User`s manual for cycle programming

CIRCULAR STUD (cycle 258, DIN/ISO: G258) 5.8

HEIDENHAIN | TNC 640 | User’s manual for cycle programming | 9/2015

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5.8 CIRCULAR STUD (cycle 258, DIN/ISO:

G258)

Cycle run

With the cycle POLYGON STUD you can create an even polygon by

machining the contour outside. The milling operation is carried out

on a spiral path, based on the diameter of the workpiece blank.

1 If, at the beginning of machining, the work piece is positioned

below the 2nd set-up clearance, the TNC will retract the tool

back to the 2nd setup clearance.

2 Starting from the center of the stud the TNC moves the tool

to the starting point of the stud machining. The starting point

depends, among others, on the diameter of the workpiece blank

and the angle of rotation of the stud. The angle of rotation is

determined with parameter Q224.

The tool moves at rapid traverse FMAX to the setup clearance

Q200 and from there with the feed rate for plunging to the first

plunging depth.

4 Then the TNC creates the polygon stud in a spiral-shaped pass,

taking into account the path overlap

5 The TNC moves the tool on a tangential path from the outside

to the inside

6 The tool will be lifted in the direction of the spindle axis to the

2nd setup clearance in one rapid movement

7 If several plunging depths are required, the TNC will position the

tool back to the starting point of the stud milling process.

8 This process is repeated until the programmed stud depth is

reached.

9 At the end of the cycle first a departing motion is performed.

Then the TNC will move the tool on the tool axis to the 2nd

setup clearance.