Preparing Artwork for Laser Cutting

Our Laser cutter is a 40W CO2 laser with a roughly A4 sized cutting area (315 x 215 mm)

It can cut most plastics and organic materials, but will not cut or mark metals directly. These rules will apply to all CO2 based laser cutters.

Good materials

• Paper and Card
• Felt and cloth
• Acrylic sheet
• Laserable rubber (for stamp making)
• Interior or Laserable Plywood
• MDF and other solid wood sheets
• Anodized metals - can be engraved by burning off the anodized layer

Bad / Forbidden materials

• PVC - Forbidden - Produces chlorine gas
• Rubber Foam - poor quality cuts, edges melt and retreat from the cut
• Polycarbonate - may discolour around the cutting/engraving point
• Metal - will not cut/mark, laser is totally reflected

Two main modes of operation Cutting and Engraving

1. Cutting works by vapourising the material in order to cut through it, the laser follows the vector path / outline of the work
2. Engraving works at lower speeds and vapourises the surface layer of the material leaving an engraved effect, the laser follows a rasterised path, scanning back and forth across the area being worked.

File Formats for Artwork

Whilst technically we can handle any image format that Inkscape can load, the laser cutter software itself is quite fussy so it will greatly speed up operations on the day if you can follow the guidelines below and produce the correctly formatted files beforehand and bring them in on a USB key.

When saving the artwork, first shrink the page size to the size of the area to be cut, ink inkscape this is done with Document Properties -> Resize page to drawing or selection. This gives you the most flexibility when positioning the artwork.

Software Update

We have updated the control software to use K40-Whisperer , this gives us much better control over the cutter, but comes with slightly more complex setup for the artwork.

Please follow the 'Creating Input for K40 Whisperer' guide on the K40 Whisperer Documentation website.

In Summary:

• SVG or DXF file only
• Red = Vector cut this shape
• Blue = Vector engrave this shape
• Black = Raster engrave this shape
• Use halftone / dithered mono images to raster engrave pictures

Cutting

The two vector cutting modes, "vector cut" and "vector engrave" are identical, except that you may define separate speeds for each. In either case the laser traces a single path along the center of the defined line, line width is ignored, RED lines trace at the 'vector cut' speed and BLUE lines trace at the 'vector engrave' speed.

This is generally a very quick operation, as it only makes one pass for each line. If it has not cut or marked sufficiently you may repeat the operation for a second pass. Make sure you have not disturbed the position of the work piece between passes.

The speed settings are limited by how complex the movements required to trace your shapes are, and how thick the piece to be cut is, generally 50 mm/s is the maximum for a moderately complex item, for cutting thick materials speeds are more likely around 10 mm/s area.

Engraving

This method is used to etch or engrave shapes into the surface of a material, this is typically used to make rubber stamps, to engrave artwork into clear acrylic, or to burn artwork into wood or similar surface.

The process involves a raster scan of the artwork, and so the source material can be bitmap or vector in nature. If you want to achieve greyscale type effects, for best result use your chosen bitmap graphics program to generate a high resolution (300dpi) 1-bit depth mono dithered image of your artwork.

Any artwork, be it vector lines, shapes, text, or bitmaps in your file that are BLACK will be raster engraved, this includes any line thickness you have set, and should appear on the work exactly as it appeared on the screen.

This process is much slower, as although you can define a much higher movement speeds (upto 500 mm/s) because it makes a predictable back and forth scanning motion, it has to make a lot of these scan lines to build up the whole image.