OCM cycles

OCM cycles

General information

 
Machine

Refer to your machine manual.

Your machine manufacturer enables this function.

Using OCM cycles (Optimized Contour Milling), you can combine subcontours to form complex contours. These cycles provide more functionality than Cycles 22 to 24. The OCM cycles feature the following additional functions:

  • When roughing, the control will maintain the specified tool angle precisely
  • Besides pockets, you can also machine islands and open pockets
 
Tip
  • Programming and operating notes:
  • You can program up to 16 384 contour elements in one OCM cycle.
  • OCM cycles conduct comprehensive and complex internal calculations as well as the resulting machining operations. For safety reasons, always verify the program graphically! This is a simple way of finding out whether the program calculated by the control will provide the desired results.

Contact angle

When roughing, the control will retain the tool angle precisely. The tool angle can be defined implicitly by specifying an overlap factor. The maximum overlap factor is 1.99; this corresponds to an angle of nearly 180°.

Contour

Specify the contour with CONTOUR DEF / SEL CONTOUR or with the OCM shape cycles 127x.

Closed pockets can also be defined in Cycle 14.

The machining dimensions, such as milling depth, allowances, and clearance height, can be entered centrally in Cycle 271 OCM CONTOUR DATA or in the 127x figure cycles.

CONTOUR DEF / SEL CONTOUR:

In CONTOUR DEF / SEL CONTOUR, the first contour can be a pocket or a boundary. The next contours can be programmed as islands or pockets. To program open pockets, use a boundary and an island.

Proceed as follows:

  1. Program CONTOUR DEF
  2. Define the first contour as a pocket and the second one as an island
  3. Define Cycle 271 OCM CONTOUR DATA
  4. In cycle parameter Q569, program the value 1
  5. The control will interpret the first contour as an open boundary instead of a pocket. Thus, the open boundary and the island programmed subsequently are combined to form an open pocket.
  6. Define Cycle 272 OCM ROUGHING
 
Tip
  • Programming notes:
  • Subsequently defined contours that are outside the first contour will not be considered.
  • The first depth of the subcontour is the cycle depth. This is the maximum depth for the programmed contour. Other subcontours cannot be deeper than the cycle depth Therefore, start programming the subcontour with the deepest pocket.

OCM figure cycles:

The figure defined in an OCM figure cycles can be a pocket, an island, or a boundary. Use the Cycles 128x for programming an island or an open pocket.

Proceed as follows:

  1. Program a figure using cycles 127x
  2. If the first figure will be an island or an open pocket, make sure to program boundary cycle 128x.
  3. Define Cycle 272 OCM ROUGHING

OCM cycles for pattern definition

Machining operation

When roughing, these cycles allow you to use larger tools for the first roughing passes and then smaller tools to take off the residual material. For finishing, the material roughed out will be taken into consideration.

Example

You defined a Ø20 mm rough-out tool. For roughing, this results in minimum inside radii of 10 mm (cycle parameter Q578 Radius factor on inside corners will not be taken into account in this example). In the next step, you will finish the contour. For this purpose, define a Ø10 mm finishing cutter. In this case, the minimum inside radii would be 5 mm. Finishing cycles will also consider the previous machining steps, depending on Q438, so that the smallest finishing inside radii will be 10 mm. Thus, the finishing cutter will be protected from overload.

Program structure: Machining with OCM cycles

0 BEGIN OCM MM

...

12 CONTOUR DEF

...

13 CYCL DEF 271 OCM CONTOUR DATA

...

16 CYCL DEF 272 OCM ROUGHING

...

17 CYCL CALL

...

20 CYCL DEF 273 OCM FINISHING FLOOR

...

21 CYCL CALL

...

24 CYCL DEF 274 OCM FINISHING SIDE

...

25 CYCL CALL

...

50 L Z+250 R0 FMAX M2

51 LBL 1

...

55 LBL 0

56 LBL 2

...

60 LBL 0

...

99 END PGM OCM MM