Process

To ensure that the cycle is executed successfully, the following requirements must be met.

• The tool radius is defined by V.G.WZ_AKT.R
• Tool length compensation is active.
• The spindle speed must be selected before the cycle is started.
• The blank can be circled at machining height without collision (see below).
• A maximum of 3 systems may be active or defined when the cycle is called to ensure that sufficient machining coordinate systems (#CS) are available for the cycle.

Within the cycle, the tool is fed incrementally along the Z axis. The starting point here is a start point which has a safety clearance to the blank set by @P13 in the XY plane and is vertically parallel to the Y axis under the spigot centre. The blank is approached in a circular or linear movement along the outer edge for each machining height. When the machining direction is clockwise (@P30=0 -> down milling), the approach is counter-clockwise and departure is clockwise. When the machining direction is counter-clockwise (@P30=1 -> up milling), the approach is clockwise and departure is counter-clockwise.

The milling operation has a helical shape for a multi-edge which has more than two edges. The milling operation has a linear shape for a multi-edge with one or two edges. The blank is continuously circled in the direction set in @P30 during the milling operation.

Attention

Collision detection by minimum clearance to blank

To permit a circular approach to the blank, it must be possible to circle the blank safely at machining height at a clearance D = [@P13 + 2 * tool radius]. The green dashed line in the graphic below describes the area in which no collision may occur.

Roughing process

At the start, the start point in the XY plane is approached at the height of the retraction plane. The infeed is first to the safety plane at rapid traverse along the Z axis followed by an infeed to the machining height at the feedrate defined by @P21. At this start point, an interative feed takes place up to the new machining height until the spigot depth @P4 is reached with the addition of the finishing allowance at the base (@P15). The maximum infeed per pass is the maximum infeed in Z at the maximum value defined in @P5.

For each machining height, the tool then approaches closer to the centre of the spigot in a circular movement each circumferential pass without exceeding the maximum feed in XY (@P6). Linear removal continues until the linear outer dimensions of the multi-edge with the addition of the finishing allowance at the edge (@P16) are removed.

When linear machining is completed, the corner radius (@P44) or the chamfer (@P66) is milled. Corner removal continues every circumferential pass around the spigot until the correct radius is reached.

To avoid jerky movements in the milling path and thus relieve the machine tool, it may be useful to activate polynomial contouring during roughing. This also leads to an accelerated execution of the milling cycle. The parameterisation of polynomial smoothing should be made dependent on the selected finishing allowance in order to avoid damage to the outer contour. To avoid residue, the maximum infeed in XY must then be reduced.

The milling cycle with polynomial smoothing can be called as follows:

#CONTOUR MODE [DEV, PATH_DEV = V.G.WZ_AKT.R / 10 ]  ( Parameterisation )

G261                             ( Activation of polynomial contouring )

L CYCLE [NAME = SysMill... ]                                ( Roughing )

G260                           ( Deactivation of polynomial contouring )

L CYCLE [NAME = SysMill... ]                               ( Finishing )

M30

Finishing process

The start point mentioned for roughing is also approached as the starting position for finishing. From there, an interative feed takes place up to the new machining height until the spigot depth @P4 is reached. The maximum infeed per pass is the maximum infeed in Z at the maximum value defined in @P5.

A distinction is made between two cases for the milling operation at each machining height:

• If no finishing allowance at the base needs to be removed at the current machining height, only the finishing allowance around the spigot is removed.
• If the current machining height also involves a removal of the finishing allowance at the base, the complete blank must be again machined at this height until the correct spigot height is reached.