// Controllers · GRBL 1.1
CAM for GRBL 1.1
Many hobby routers and DIY machines run GRBL (for example machines sent from gSender, UGS, CNCjs or OpenBuilds CONTROL).
Checked by the controller's own parser
What the GRBL 1.1 post writes
- G20 / G21 for inches or millimetres, G90 absolute
- Tool changes as a pause (M0) with the next tool named in a comment
- Dwell G4 P in seconds
- Arcs with I J; holes as moves (GRBL has no drilling cycles)
Files end in .nc. Every file is read back before export and checked against the simulated toolpath.
GRBL ignores M6, so a tool change is a pause: swap the tool, set Z zero again, resume.
Where this post comes from
- The controller's own parser, in our tests: GRBL 1.1h (gnea/grbl) reads every test job without an error
- The controller maker: GRBL wiki (gnea/grbl)
- Another CAM program: Autodesk Fusion Grbl post (2026)
Not yet confirmed on a machine. This post follows the sources above. Before the first real job, run the controller check in the air, or compare with a file that already runs on your machine (Export options → Check this post).