Laser Cutting

Overview

Laser cutting is a process that uses a high-power laser to cut through or mark the surface of materials. In order to have a file laser cut, you will need to drop off an Adobe Illustrator file and the material that we will be cutting this file from. Before dropping off a file, please be sure to read the information provided here in full and allow for at least 48hrs for turn around.

Equipment

The RP Centre has two CO2 laser cutters:

  • Trotec Speedy 500, 120 watt CO2 Laser cutter with a 48" x 27" size bed
  • Universal, 150watt CO2 Laser cutter with a 32” x 18” size bed

Pricing

Laser cutting is charged at $1/min +$6 set-up fee

Materials

You will need to provide your own materials for laser cutting. We are able to work with a wide range of materials up to a thickness of ¼”:

  • Acrylic
  • Plywood
  • Fabric
  • Leather
  • Single-wall Cardboard
  • Paper
  • Matboard

You can find most of these materials available for sale in the OCAD Plastic Shop, Wood Shop and in Above Ground Art Supplies.

Please note that for safety reasons there are some materials that we will not cut:

  • Acrylonitrile butadiene styrene (ABS)
  • Double Wall Corrugated Cardboard
  • Foam-core/Polystyrene presentation board
  • Pleather/fake leather
  • Vinyl
  • Polycarbonate/Lexan
  • PVC (Polyvinyl Chloride)
  • Styrene

If you are looking to work with a material not listed here, please bring in a sample to discuss with an RP staff member.

Preparing your files

Files that will be used for laser cutting need to be vector files. These can be prepared in Auto CAD, Corel Draw, Inkscape or Adobe Illustrator. We ask that you save your file as an Adobe Illustrator file before dropping it off in the RP Centre. If you have any questions about this, please ask an RP staff member.

If you need help getting started with Adobe Illustrator for the first time, take a look at these Online Illustrator Tutorials.

We also recommend Lynda tutorials available to OCAD students here:
https://www.ocadu.ca/services/it/wireless-and-web-services/lynda.htm

5 steps to successful laser cutting:

1. Our machines have a maximum bed size of: 48" x 27" and 32” x 18”.
Please keep these limits in mind when preparing your files and buying material.
We also ask that you bring in material no smaller than 3 x 3”

2. Adjust the artboard of your file to match the material that you are bringing in. This ensures that your artwork will fit on your material.

STEP 2

Because our machines work in inches, we would also ask that you set up your file in inches. You can adjust this when you first open a new file, or by right-clicking (or control-clicking) on the rulers.

3. Make sure you are working in RGB mode, NOT CMYK. You can change this by going to: Select File ->Document Colour Mode -> RGB

STEP 3

Once in RGB-mode, you can find the basic RGB colour swatch Select Swatch Library Menu -> Default Swatches -> Basic RGB Raster Lines and Fills

4.

STEP 4

All cut lines need to be indicated using Red Blue and Green lines with a stroke weight of .01pt

The laser will interpret the colours as ordered cut lines working from the inside out. Starting with Red (RGB: 255, 0, 0) followed by Blue (RGB 0,0,255), and finally Green (RGB 0,255,0). All interior cuts should be cut first and therefore should be red, with any further cuts being Blue, and the final exterior cuts being Green.

Rastering (or engraving) is achieved by using black lines and fills in your file.

Different depths of rastering can be achieved by using several tones of grey.
Black will always be rastered the deepest, with White not being touched. The darkness of the Grey tone will determine how deep the raster will be. However to achieve the rastering effect, the laser passes over an object hundreds of times removing one beam width per pass. This means very large rastering jobs can get very expensive! Use this technique wisely. Also note, that while we can do deep or shallow engraving, we cannot engrave to a specific depth.

Linear engraving is a fine-line engraving that is achieved by running a low power cut-line. This is indicated in your file by having a black line .1pt.

Donut example

5. If you are using text in your file, please be sure that you change it to outlines before dropping off your file. We will most likely not have the font that you are working with, by converting your text to outlines you ensure that the text looks the way you intend it to.

STEP 5

Laser cutting tips and tricks

Cutting out text

Using a stencil font will prevent the middle islands of some letters to fall out when laser cut. If you don’t use a stencil font, the text can be difficult to read. You may also want to open up the kerning of the text for better legibility.

text example

Nesting:

If compiling a file with lots of components on one sheet of material, make sure there is a gap of at least 1/8” or 3mm between the components.

Small details / cut widths:

We recommend that minimum cut widths be no smaller than 1/16” We can go smaller but things can get quite fragile and we cannot guarantee it will work.

Clean vectors:

Before dropping off your work check that your vector lines are joined and that there are no overlapping lines in your file. Also check that there are no vector paths hidden behind white shape fills.

Kerf:

Because laser cutting is a heat based process, some material vaporizes during cutting which results in some space being created on either side of the laser beam- this space is called the kerf. If you are working on something that needs to be of a very specific size (ie. Finger joints, inlays etc.) it is important to take into consideration how the laser's kerf will affect the final result.

The exact size of the laser kerf depends on many variables, including:

  • The material you are cutting
  • The thickness of the material you are cutting through
  • The wear of the gantry that moves the laser head around
  • The power of the laser you are cutting with
  • The strength of the air assist
  • The direction of the woodgrain, if you are cutting wood

If exact fit is crucial, we recommend doing a fit test before you cut your final work.

It is also worth mentioning that laser cutters will cut materials at a very slight angle- wider at the top and narrower towards the bottom. This is generally not very noticeable, but can affect some applications particularly when working with thicker material.

kerf-illustration

Additional resources

Joyoflasercutting.com

Lynda.com