Setting up specific routines to allow for automatic tool changers or changing the way the tool description is output in comments.
It converts toolpaths (3-axis, multi-axis, lathe, EDM) into a "dialect" of G-code that your machine understands. Why Edit? While generic posts work, editing allows you to:
Your post processor is not a static file. It is a living reflection of your machine shop’s standards. Every time you buy a new machine, a new probe (Renishaw), or a new bar feeder, your post will need editing.
pdrill$ # Canned Drill Cycle if mi6$ = 1, "G81", pfzout, pfrout, e$ # Output G81 for standard drilling else, "G83", pfzout, pfrout, "Q", "0.1", e$ # Output G83 with Q value for peck drilling
Mastercam provides a dedicated Post Processor Editor to view and modify these files. It supports syntax highlighting and comments, making it easier to read and debug the code. Essential Safety Measures mastercam post processor editing
Mastercam provides built-in "switch" variables that let you control output without complex scripting. Two key types of variables can make customizing a new post much easier.
Introduction to Post Processors in Fusion [Update 2025] - Autodesk
Perform a dry run on the CNC machine (preferably with no tool or part) to ensure the motions are correct. Conclusion
What are you trying to make to your G-code output? Setting up specific routines to allow for automatic
Register now to participate in the forums, access the download area, buy Mastercam training materials, post processors and more. * eMastercam.com Opening a post for editing - eMastercam.com
The Ultimate Guide to Mastercam Post Processor Editing A Mastercam post processor is the critical bridge between your digital CAD/CAM design and your physical CNC machine. It translates Mastercam’s internal toolpath data (NCI files) into the specific G-code dialect your machine controller understands.
What Is a CNC Post Processor and Why Do I Need One? - Tormach
Variable Definitions: This is where you initialize the data holders for coordinates, feed rates, and logic switches.Formatting Statements: These lines dictate how numbers appear in the G-code, such as the number of decimal places or the inclusion of leading/trailing zeros.Predefined Blocks: These are the "events" in the code, such as the start of a file, a tool change, or the end of a program.Lookup Tables: These maps correlate Mastercam internal values to specific machine G and M codes. Setting Up Your Environment While generic posts work, editing allows you to:
For deeper edits—like changing tool change sequences or adding custom M-codes—you’ll need to work with the . How to edit post processors - eMastercam.com
Out of the box, Mastercam comes with generic post processors (MPFAN, MPLFAN, etc.). These are fantastic for general use, but they are precisely that: generic. If you run a Haas VF-2 with a 4th axis rotary, a laser cutter, a waterjet, or a Okuma Multus B-axis lathe, the generic post will fail. It might output the wrong G-code, ignore your coolant commands, or, worst of all, crash your spindle.
# General Output Settings progname$ : 1 # Use program name from Mastercam spaces$ : 0 # Add spaces between addresses (0=no, 1=yes) omitseq$ : yes # Omit sequence numbers? seqno$ : 2 # Start sequence number at N2
psof$ pbld, n$, "G20" (Inch mode) pbld, n$, "G90 G80 G40 G17" (Absolute, cancel canned cycle/cutter comp) pbld, n$, "G91 G28 Z0." (Send Z home) pbld, n$, "G90 G54" (First work offset) pbld, n$, "M01" (Optional stop for operator check) e$