Bad Output (Standard FANUC post):
The Siemens 828D is one of the most powerful and versatile CNC controls for shop-floor machining. It bridges the gap between basic pocket milling and complex, multi-axis interpolation. However, its power comes with a unique programming language (DIN/ISO with Siemens cycles) that differs significantly from standard FANUC or Haas controls.
Mastering the Siemens 828D: The Ultimate Guide to the Mastercam Post Processor
Using the wrong post processor for a Siemens 828D is like speaking French to a German engineer—neither side understands the other. A dedicated Mastercam post processor for the 828D unlocks the true potential of the control, allowing you to use advanced cycles, high-speed machining, and rigid tapping without manual editing.
MCALL CYCLE83(1., 0., 1., -25., , 1., , 1., 1., 1., 1., 1., 1.) MCALL CYCLE84(1., 0., 1., -12., , 1., , 1., 1., 1., 1000., 2000.) MCALL Notice how the Siemens post uses MCALL to activate the cycle and parentheses for all parameters. This is what makes the 828D so powerful.
G83 Z-1.0 R0.1 Q0.1 F10. (Alarm: Unknown G code) M29 S1000 (Alarm: Siemens doesn't use M29) G84 Z-0.5 R0.1 F20. Good Output (Siemens 828D post):
In this article, we will break down why the 828D requires a specialized post, the critical features you must look for, and how to troubleshoot common output issues.
| Error on 828D | Likely Cause | Mastercam Fix | | :--- | :--- | :--- | | "Axis not configured" | Post output A or B instead of C . | Verify rotary axis labels in the post (Rotary Axis Settings). | | "Drilling cycle incomplete" | Missing RTP (Return plane) or RFP (Reference plane). | Update the post formatting for drillcyc block. | | "Wrong G code" | Post output G84 for tapping. | Force the post to output CYCLE84 instead of G84. | | "Spindle speed missing" | M03 issued before S word. | Change the order of output variables in the post (S before M03). |
The post should convert Mastercam’s standard drilling and tapping operations into Siemens cycle format, not long-hand G-code. This keeps the program size small and allows the operator to edit peck depths or dwell times easily at the control.
Do you use a Siemens 828D with Mastercam? Share your biggest post-processing headache in the comments below.
Open your Mastercam post file (.pst) and search for CYCLE83 . If you don't find it, you are losing efficiency.
Most CNC controls read G-code line-by-line in a modal fashion. The Siemens 828D, however, operates heavily on software boundaries and parameterized cycles (CYCLE83, CYCLE84, CYCLE832). It also uses different codes for High-Speed Machining (HSM).
When purchasing or customizing a post for the 828D, ensure it includes the following: