Typical modifications
- Change header, comments and program numbering.
- Add or correct MTB M-codes (clamps, coolant types, air blast).
- Fix arc output, plane selection or helical moves.
- Correct rotary directions or limits.
- Add probing, tool breakage checks or custom macros.
- Support a new controller version or option.
Where optimisation saves cycle time
| Optimisation | Typical gain |
|---|---|
| Remove full retracts to home between operations with the same tool | Seconds per operation, minutes per program |
| Pre-select next tool during cutting | 1–3 seconds per tool change |
| Use canned cycles instead of expanded moves | Shorter programs, faster block processing |
| Enable high-speed / look-ahead modes (e.g. FANUC G05.1 Q1, Siemens CYCLE832) | Smoother, faster 3D finishing |
| Output arcs instead of short linear segments where accurate | Smaller files, better surface |
| Optimise rotary paths and avoid unnecessary unwinds | Less non-cutting time on 4/5-axis |
Before and after
(Before: full retract between two ops with the same tool)
G91 G28 Z0.
M05
M09
G90 G54 X40. Y10. S9000 M03
G43 H01 Z50. M08
(After: stay on tool, move at clearance height)
G00 Z25.
X40. Y10.Our approach
- Review the existing post and a set of real programs.
- List issues and optimisation opportunities with estimated benefit.
- Modify under version control, keeping a copy of the original.
- Re-test all operation types, not just the changed ones.
- Simulate and prove on the machine.
A note on locked posts
Some posts supplied by resellers are encrypted. Modifying them may require the original source or permission from the supplier; otherwise, a new post can be developed from a proven base.
Small post changes, repeated on every program, add up to large time savings.
Optimise your existing posts
See our CNC post processor development service and how posts improve programming productivity.