Laser Cutting (G-Code) from Pepakura

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This tutorial shows how to export outlines from Pepakura to be cut on a laser cutter/engraver. This tutorial assumes you are using Windows 7.

Installing a Postscript Printer Driver

  • Click "Start", "Devices and Printers"
  • Click "Add a printer"
  • Click "Add a local printer"
  • Select "Use an existing port", "FILE: Print to File"
  • Click "Windows Update" and wait...
  • Select the "Generic" manufacturer and the "MS Publisher Color Printer"
  • Complete the wizard

Install PSToEdit and prerequisites

  • Download and install Ghostscript and GSView from the Ghostscript website
  • If you are on a 64 bit machine, copy C:\Program Files\gs\gs9.05\bin\gswin64c.exe to C:\Program Files\gs\gs9.05\bin\gswin32c.exe
  • Download and install PSToEdit
  • Download and install Inkscape
  • If your laser cutter speaks G-CODE, install GcodeTools for Inkscape

Print Your Model

  • Launch Pepakura and open your model
  • Set the page up to match your laser: Select "File", "Print and Paper Settings", "Paper Size" -> "Other", "Width" -> "305", "Height" -> "220", "Side Margin" -> "30", "Top/Bottom Margin" -> "15"
  • Select "Print Lines clearly (Vector Print)"
  • Select "Print page number" and "Print Alignment marks for multiple pages", "OK"
  • Select "2D Menu", "Recalculate Parts Layout", "Auto", "OK"
  • Select "File", "Printer Setup", "Size" -> "A4", "Orientation" -> "Landscape"
  • Select "File", "Print", "MS Publisher Color Printer" and save the printout (do not adjust the scale)

Convert to SVG

  • Locate your file in Windows Explorer and open it in GSView/GSView64. You should have a menu above the image, if not. it means you have opened it with GSWin rather than GSView
  • Select "Edit", "Convert to Vector Format"
  • Select "SVG" and click "OK"
  • Select the pages to convert
  • Save the file

Prepare Your SVG

  • Open the SVG in Inkscape
  • Set the page up to match your laser: "File", "Document Properties", "Default Units" -> "mm", "Width" -> "245 mm", "Height" -> "190 mm"
  • Note that the scale of objects may have been lost in the conversion. Rescale the objects if necessary: Select the group of objects, click the aspect ratio lock (next to the width), then set the width to 245 mm and X & Y to 0
  • Draw 2 circles to act as registration marks between the printout and laser cutting: First: W=1 H=1 X=-0.5 Y=-0.5, Second: W=1 H=1 X=244.5 Y=189.5 (These circles will be centred on 0,0 and 245,190)
  • Save your image for future reference
  • Print your image to your printer. If the edges are cropped, you may get better results by saving as a PDF and printing from Acrobat.

Convert the Outlines to Gcode

  • Delete all bitmaps, registration marks, text and other objects you don't want lasercut. Note that the bitmap textures are a grid of individual bitmaps, and need to be deleted individually. You can Select All (control-A) to see what objects you have left
  • "Layer", "Add Layer"
  • "Layer", "Layers"
  • Select all the objects
  • "Object", "Group"
  • Reselect the new group
  • "Layer", "Move selection to layer below"
  • Confirm the objects are now on the new layer by clicking the show/hide icon (eye) in the layers tab
  • "Path", "Object to Path"
  • "Extensions", "GCodeTools", "Orientation Points", "2 Points Mode", "Apply"
  • Select the new orientation points and relocate them to X: 0 Y : 0
  • "Extensions", "GCodeTools", "Tool Library", "Default", "Apply"
  • Adjust the settings using the text tool to suit your laser. For Alastair's laser: Diameter: 0.3  Feed 400   Spindle RPM: 100
  • "File", "Save As", "filename_laser.svg"
  • "Extensions", "GCodeTools", "Path to GCode", "Apply"