Intro to Laser Cutting and Etching

Introduction

The Laser Cut Notebook Cover with a Living Hinge has been my favorite project since I first started working on it, almost one year ago.  I first designed this project for my composition notebooks, since I always have one with me for jotting down notes.  The initial living hinge pattern was found on Epilog Sample Club, a website with great ideas for laser cutter projects.  Then, when I was asked for a fun project to contribute to TechShop Ladies Night, my first suggestion was this project.  Since it’s a personal favorite, I’ve created a tutorial that goes over how to prepare a notebook from start to finish.


Since this project is done in Adobe Illustrator, I designed the tutorial to be an introduction to the vector software.  First, we will use Adobe Illustrator to create artwork on the computer.  We’ll go over the difference between raster and vector art and a brief introduction to vector art.  Then, we’ll move to the laser cutters to etch the art we created and cut the living hinge pattern into wood.  You will need access to a laser cutter in order to finish the project.  However, I also recommend this tutorial if you are learning to create art in Illustrator.

Intro to Laser Cutting and Etching

A laser system is used to etch, engrave, or cut a variety of materials.  In this Tutorial, we’ll be using the Universal Laser system, which are 60W ULS machines with 24” x 18” work areas.  Most wood and acrylic that is sold for laser cutting already comes in 24” x 18” sheets that are ⅛” or ¼” thick.  By etching into the surface of the wood, we can “print” artwork on wood.

In addition to etching, we’ll also cut a narrow pattern of lines that makes the flat wood flexible.  This is called a living hinge because the hinge is incorporated into the final material, rather than an added piece of hardware.

Laser cutters operate similarly to printers.  First you’ll design your art on the computer in Adobe Illustrator.  After laying your sheet of wood on the laser bed, you’ll choose settings and click  “Print” in the File menu.  

Raster vs Vector

The Laser system uses two functions to create art, and these terms will be used throughout today’s workshop: Raster and Vector.  

A raster pattern is used to etch the material, putting down “dots of heat,” similar to the way an inkjet printer prints with ink. Raster data is made of pixels. Any image that you copy and paste into Illustrator will be a raster image.  File types of jpg, gif, png, and bmp are all examples of raster data.

The laser will read black and grey areas and translate them into Pixels Per Inch, resulting in the imaged burned into the surface of wood.  Raster art needs to be in black or grayscale for the laser to recognize it.  We recommend you Live Trace any raster artwork in Illustrator to eliminate visible pixels in the final laser art.

Vector patterns are used to score or cut through material. When following vectors, the laser moves like a plotter and follows your vector paths to draw or carve them into your material. Vector data is expressed in lines – straight lines, circles, rectangles, splines, and hand-drawn squiggly curves are all examples of vector data. The line thickness in Illustrator must be .001 or hairline in CorelDRAW to be considered vectors by the print driver.

Line Color and the Universal Laser System

In addition to line weight and fill, the Universal lasers also use RGB colors to determine if you are cutting or etching.

Red lines are used to signify vector cuts, which is when the laser goes all the way through your material. Vector cut lines must be .001 thickness in Illustrator or hairline in CoreDRAW.

Blue lines are used to signify vector engraving. Engraving etches the surface of your material but does not cut all the way through. You might use engraving to create fold lines on heavy paper, for example.

The color Black represents raster data. Raster data takes a variety of forms from thick lines, to simple shapes, to complex pictures. If you’re trying to raster a color picture, you’ll need to convert it to grayscale before sending it to the laser.

You can use a combination of Red, Blue and Black, and .001 pt stroke or fills to create your art.  Remember that the Universal laser system will read any lines that are .001 and Red or Blue as Vector Cut or Vector Etch Lines.  Alternatively, any art that is black and more than .001 stroke will be rastered, or Etched into the surface of the wood.

It’s a good idea to click on all of your art to double check that it is set up the way you want to print it.