G-code Toolpath and Print Viewer will not open? Format and display troubleshooting
Troubleshoot G-code Toolpath and Print Viewer by checking signatures, versions, units, coordinates, and browser resources while preserving the source.
Do not rename or overwrite the source first
Make a sample copy and retain the original delivery, size, producer version, and exact error. For FDM G-code, confirm G21 millimeters and G90 absolute positioning, then inspect first-layer bounds, nozzle/bed temperatures, and extrusion. For CNC, search G54, G43, M6, and spindle commands.
Recommended troubleshooting order
- Test the page example or a smaller known-good file to confirm browser functionality.
- Check that the file signature matches its extension and it is not a downloaded HTML error page.
- Compare the supported formats and size limit with the specialist checks below.
- Close other heavy tabs and retry in current Chrome or Edge.
- If it still fails, re-export from the producing application and verify in authoritative specialist software.
Checks for this format
- G20/G21 units and G90/G91 positioning are explicit
- XYZ bounds stay within machine travel or print bed
- Rapid and extrusion/cutting moves are distinguishable without suspicious crossings
- Homing, work coordinates, temperature, spindle, and tool changes fit the target controller
Common errors and fixes
The model is scaled by 25.4
This normally means inch/mm interpretation is wrong; inspect G20/G21 and CAM/slicer export units.
The preview is right but the machine moves differently
Firmware macros, offsets, compensation, and vendor codes are interpreted by the real controller and are not simulated here.
When a browser tool is insufficient
- Macros, subprograms, vendor extensions, and five-axis motion may be unsupported
- Time estimates omit real acceleration, firmware planning, and tool changes
- A preview cannot prove machine, fixture, or work-coordinate safety
A visible preview only proves this parser read some structures. It does not prove engineering, manufacturing, scientific, business, or clinical compliance. Keep validation records from the source and receiving systems.
Privacy and safety
The tool reads files locally and does not upload them to FreeTool for parsing. Troubleshooting screenshots, CSV exports, and downloads can still contain sensitive data; de-identify before sharing and clear copies from shared devices.