README

example

G-Code Generator

Utility to create G-Code for drilling, milling and text engraving from a simple JSON input file.

The generator can generate G-Code for:

Drill holes
Rectangles
Circles
Text Engraving

Rectangles and Circles are done in a spiral rough cut and a last fine cut.

WARNING: USE AT YOUR OWN RISK!

Please learn a little bit of G-Code (it is easy) to understand what you are doing: https://www.reprap.org/wiki/G-code

I.e. have a look at M3/M5/G2/G21/G92/G0/G1/G2/G3

Installation

sudo npm install --global gcode-gen

How To Use

IMPORTANT: all files start with G92 to zero the coordinates from the current position. You must remove it from the output if you want a different behavior.

1st Step: Generate the G-Code

Example:

gcode-gen examples/A-Z0-9.json > examples/A-Z0-9.gcode

2nd step: Double check the G-Code output

BTW: CAMotics is a great tool toto review the G-Code in 3d

3nd Step: Prepare and run the machine

IMPORTANT: all files start with G92 to set the current position as zero coordinates.

Move the tool to the desired (0,0) point, and move the z-axis down, so the tool touches the surface slightly. (Hint: i use s sheet of thin paper - if I can't move it any more, it is OK ;-)

Use your favorite G-Code sender tool - I use GRBL Controller

Example JSON Input

{ 
  "PrjName": "Example",
  "ToolDia": 3.0,
  "SafeHeight": 3,
  "CutSpeed":200,
  "SpindleSpeed":1000,
  "z": -2.5,
  "passes": 4,
  "Template": {
    "AudioCh": [
      { "type": "Circle", "x":10, "y": 10, "r":10, "descr":"a circle  },
    ]
  },
  "DoTemplates": [
    { "Template": "Test", "x":  0.0, "y":  0.0, "descr":"Test" }
  ]
}

JSON explained:

"ToolDia": in mm
"CutSpeed": feed rate in mm per min (optional, default 200)
"z": negative value, depth to cut in mm (or material thickness + some 1/10 mm)
"fontZ": optional (negative mm) depth for text engravings
"passes": passes to cut to z depth (optional, default 4)
"fine": number in mm to reduce size for raw cut of rectangle/circle, then cut this to final size
"Template": named lists of objects of:
- "type": "Drill" thru drill at "x", "y"
- "type": "Circle" center "x", "y" and radius "r"
- "type": "Rectangle" center "x", "y", width "w" and height "h"
- "type": "Text" left lower corner "x", "y", the "text" to engrave and the "size" in mm
  - optional: "mirror": true
  - optional: rotation "dir" in degree
- "type": "Template" to re-use other templates
"DoTemplates": list of templates to process with specified "x" and "y"

Each object can have a "descr" text, which is used in a comment.

See examples folder for more JSON examples.

Text Engraving

The "text can be capital letters, numbers, space and a "-". Text can be rotated and/or mirrored.

{ 
  "PrjName": "Text Rotation Example",
  "ToolDia": 3.0,
  "SafeHeight": 3,
  "CutSpeed":200,
  "SpindleSpeed":1000,
  "fontZ": -0.05,
  "Template": {
    "TextRot": [
      { "type": "Text", "x":0, "y": 0, "text":" - ACBD-", "size":4, "dir": 45, "descr":"Text 90° mirrored" },
      { "type": "Text", "x":0, "y": 0, "text":" - ACBD-", "size":4, "dir":180, "mirror": true, "descr":"Text 90° mirrored" }
    ]
  },
  "DoTemplates": [
    { "Template": "TextRot", "x":  0.0, "y":  0.0, "descr":"Test" }
  ]
}

You can modify, extend the fonts or create your own fonts: Clone the repo locally and edit gcode-gen.js and modify the functions initArialNormal or initArialSmall. You can use the gCodeABC.js helper script to generate fonts from an Inkscape G-Code export.

Usage no npm install needed!