Laser cutters are machines that use focused laser light to cut sheet goods and films. They are mostly used to create 2-D patterns and shapes like a scroll-saw but with more control and precision. 3-D objects are created by joining 2-D parts together. A typical laser cutter has a stationary laser (they can be physically large) and some drive mechanisms to move mirrors (in the X-Y plane) and position the focused laser beam over the workpiece as it cuts. Laser cutters can also be used to mark or engrave patterns in a workpiece.
lab64 training or CA assistance is REQUIRED to use the laser cutter!
Read the entire tutorial below and come to CA office hours OR reach out to us in the #training-request Slack channel to receive training.
After completing the training, you will need your own account on the Trotec laser cutter computer to use the laser cutter outside of CA office hours. The lab64 CA's will submit a request for you to get an account once you've completed training.
Note that this request may take a few days to process, so please plan ahead. Once you've received your account and completed the in-person portion of the training, a CA or Jeff Stribling will need to activate Job Control on your account.
Materials You Can Cut
Materials you SHOULD NOT & Cannot cut
DO NOT CUT ANY MATERIAL THAT GENERATES CHLORINE GAS !!
For example, DO NOT CUT PVC (polyvinyl chloride)
Preparing Your File
Open your design in Inkscape
Adjust the stroke width/color of your design in Inkscape
Send your design in Inkscape to the JobControl software that runs the Trotec laser cutter
Target File Format
In order to laser cut with the Trotec laser cutter, you will need to open and modify your file using Inkscape on the laser cutter computer.
Some formats Inkscape can open include:
DXF, PDF, AI, SVG, EPS, JPEG, and PNG
sending a file from Inkscape to job control
Open your file in Inkscape
Verify that Inkscape did not scale your part incorrectly by selecting a stroke line and checking that its length is what you expect (see the W: and H: windows on the top of the toolbar)
Select all of the lines you wish to cut and go to the Fill and Stroke menu (Note: if the Fill and Stroke menu is gone, select Shift+Ctrl+F or Object - "Fill and Stroke" to bring it up)
Stroke paint: Set the line color to 255 red (or any of the other 15 different colors understood by Job Control)
Stroke style: Set the line thickness to 0.1pt
If your canvas size is very large, check its dimensions by going to File - Document properties (Shift + Ctrl + D). Modify your canvas size if necessary to make the canvas smaller than the bed of the laser cutter. Job Control will otherwise throw an error stating that it cannot load your job.
Once ready to laser cut, go to File -> Print and select Trotec as your printer.
Designing a File for Laser Cutting
Account for the kerf
The kerf is the width of the laser cutter beam that cuts into the part. This width is typically between 0.001'' and 0.01'', depending on the material and settings chosen.
Important: whenever designing pieces that will fit together, adjust your dimensions such that they account for the kerf and make test pieces before cutting out your entire designs
Because the laser beam forms a cone when cutting, slightly more material will be removed on the top of the material than on the bottom, as shown in the image to the right. The thicker the material, the more noticeable this effect is.
Circles will never be perfectly circular, especially small ones. If you want more circular holes, consider laser cutting small starter holes, and finishing them with a drill.
Burn marks may appear on your material after cutting, especially on the bottom of the material because the laser beam may bounce off the bottom metal honeycomb structure and onto the bottom of your material. Place a layer of the white masking material we provide on the bottom of the material you want to cut to protect your final piece from having burn marks.
No cut widths should be smaller than the thickness of the material. This means that if your part is 0.125in thick, then your part should not contain pieces less than 0.125in wide.
Designing a part in CAD
If you are modeling your part in CAD, make the thickness of your material a global variable. Once you're ready to cut, use calipers to measure the actual thickness of your material and update the value of the global variable. This will automatically adjust any features in your CAD that depend on the thickness of your material, and save you a lot of time.