Mastercam Post Processor Editing: A Comprehensive Guide to Customization
In the world of Mastercam, the Post Processor is the silent gatekeeper between your CAM toolpath and your machine’s motion. When it works, you never think about it. When it fails, it crashes tools, scraps parts, or stops the spindle cold.
Ensure that changes made inside your post processor script match the settings allocated inside your Mastercam Machine and Control Definition files ( .mcam-control ).
Adjusting how 4th or 5th axis movements are formatted. 5. Testing and Validation
The post outputs G91 G28 Z0. (incremental return), but your machine prefers G53 Z0. (machine coordinates). Solution: Find pretract or pcan . Replace the G91 G28 Z0. with G53 Z0. and remove the G90 that might be missing afterward. mastercam post processor editing
What are you targeting (e.g., Fanuc, Haas, Heidenhain)?
Different machines use different M-codes for high-pressure or through-spindle coolant. Locate the coolant allocation section (often formatted as string select tables like fstrsel ) to remap your codes. Locate sm08 and change it to M08 for standard flood.
If you are just getting started, refer to the official Mastercam Post Processor User Guide for detailed syntax information.
A post processor is a critical component of the CAD/CAM workflow, responsible for translating the toolpath data generated by Mastercam into a machine-specific code that the CNC machine can understand. The post processor acts as a bridge between the CAM system and the CNC machine, ensuring that the machining instructions are accurately executed. Mastercam Post Processor Editing: A Comprehensive Guide to
or your initials) to mark every change you make. This makes it easy to search for your modifications later. Top Resource Links adding / editing tool comments - eMastercam.com
Many post processors include a "switch" section at the top of the file. These are simple variables (usually
He loaded the new code into the Haas. The machine moved fluidly, stopping exactly where he'd programmed it to. Jack breathed a sigh of relief—he had successfully "taught" the machine a new trick. How to edit post processors - eMastercam.com
Variables control specific machine functions like coolant types, rigid tapping, or high-speed machining cycles. They are usually toggled using binary switches ( 0 for off, 1 for on). Ensure that changes made inside your post processor
While Mastercam provides a range of pre-configured post processors for various CNC machines, there are often specific requirements or customizations needed for a particular machining process or industry. This is where post processor editing comes into play. By modifying the post processor, users can:
This section initializes variables, sets mathematical constants, and defines formatting. For example, you define whether a variable outputs as an integer (no decimal) or a real number (with decimals). Formats and Formatting Assignments ( fmt )
Mastercam primarily utilizes two post processor formats depending on the version and machine complexity: the traditional .PST (and .SET ) architecture and the advanced .MP_POST format. Key File Components
Specifies the physical kinematics and axis configurations of your CNC machine. The Structure of a .PST File A standard .PST file is organized into distinct sections: Revision Log: Tracks changes made to the post over time.