Creo CNC

[bparker]

Hello,

  I am programming large components using the Prismatic & Multi-Surface Milling and Complete Machining options. I am very close to the z limit of the machine. Retracts are a problem. I have a few questions if I may:

1. I am programming a 3 axis conventional milling sequence. Is it possible to use a retract plane that is not       perpendicular to the tool centerline?

2. I have tried setting up a cylindrical retract plane. Is this allowed with conventional milling?

I have read the help on this topic. I can define a cylindrical retract surface in the operation but not in the sequence.

3. If the retract direction has to be aligned with the tool centerline is there a way to limit the retract distance by defining a distance from the machined surface (following shape contours) at all locations - let's say one inch?

Thank you,

Barry Parker

[sacquarone]

Hello @bparker 

In 3 Axs Machining, for the defintion of the Retract Surface, you have no other choice than specifying a Plane normal to Z axis of Sequence CSYS (most of the time aligned with OP CSYS).

Now, if your issue is related to large components (close to Machine Size), you may prefer avoiding completly the retracts in your sequences. For this purpose most of Pro/NC Sequences propses access to CUSTOMIZE_AUTO_RETRACT Pro/NC Parameter. Whe set to NO, tool stops at the end of the toolpath, without retracting. You may then add an additional GOTO POINT (in Tool Motions) at the end of each sequence, in order to be in a "good position" for the successive sequence to manufacture later on.

This Pro/NC Parameter:

• is documented in Milling Parameters section of Creo 8.0 Help Center
• Had an issue in profile sequences, but fixed in latest Creo versions (see article 303288)
• Behaves as illustrated in article 357570

Hope this will help to resolve the challenge you're currently facing.

Regards,

Serge

[bparker]

Serge,

  Thank you for your suggestion. I will take a look at this configuration option and the use of tool motions. I have been using tool motions but not in coordination with the CUSTOMIZE_AUTO_RETRACT option.

I perceive that it would be nice if the parameters for 3 axis sequences included a tilt angle for 4th axis positioning rather than orienting with a coordinate system.

Thanks again,

Barry

[bparker]

By the way, I also tried using a 4 axis approach and applying specific tilt and zero degree lead angles in order to lock-out fourth axis movement. It did not work as I had hoped.