ISEL to G-code Converter

Windows GUI application that converts ISEL CAM files into standard G-code (NC) programs for CNC machines.

Features

• Dark-mode GUI with drag & drop or file browser
• Coordinate conversion — ISEL integer coordinates (×1000) to mm
• Feed conversion — ISEL VEL values to G-code F feed rates
• Two output modes:
  • G1 linearised — arcs expanded into short line segments (numpy-accelerated when available)
  • G2/G3 arc commands — true arc output with full-circle detection (R format, split into two semicircles for controller compatibility)
• Spindle handling — S... M03 from SPINDLE CW, with M05/M30 program end
• Toolpath preview — top-down and isometric views with grid, pan, and zoom
• Estimated cycle time shown after conversion
• Single-file .exe (PyInstaller) — no Python installation required

Usage

1. Download the latest release (ISEL_to_Gcode.exe) from the Releases page.
2. Run the executable.
3. Drag & drop your ISEL file onto the window (or click Browse).
4. Optionally enable Use G2/G3 arc commands if your controller supports arcs.
5. Click Convert and choose a save location (.ngc).
6. Open Preview to inspect the toolpath before running the program.

⚠ The estimated program time is an approximation and may differ from actual machine time depending on machine parameters.

Output format

Programs start with a standard header and end with spindle stop:

N00001 G21
N00002 G17
N00003 G40
N00004 G49
N00005 G90
N00006 G94
N00007 G0 Z...        ← first Z safe retract
N00008 S1200 M03      ← spindle starts after the tool is clear
...
M05
M30

The first spindle command is emitted after the first Z safe retract, so the spindle starts turning only once the tool is clear of the workpiece. Subsequent spindle speed changes are emitted immediately.

Building from source

Requires Python 3.10+ on Windows.

pip install pyinstaller tkinterdnd2 numpy
pyinstaller --onefile --windowed --icon=icon.ico --collect-all tkinterdnd2 --hidden-import=numpy --name ISEL_to_Gcode isel_to_gcode_gui.py

The executable is created in dist\.

A release build is also triggered automatically by GitHub Actions when a new release is published.