Laser Cut Process

The process required to get a part laser cut in similar in steps to a 3d printer; you export your file to cut in a specific format, load it into software to prepare it for cutting, and then run the cut job. however, the software and specific steps vary quite a bit. This guide is meant to give you a basic overview of the process, and will not cover every step in detail of the cutting process. Attend a training session, or speak to a lab manager to learn more about how to run a laser cut.

Step 0: Should you laser cut this?

Like 3d printing, Laser cutting is a good tool for certain shapes, but sometimes it is not the ideal way of doing things.

  • Laser cutters cannot cut very think material very well (1/4″ and under is ideal), and will produce tapered cuts as your material thickness increases. this means that  the edge of your cut may not be perfectly perpendicular to the top
A diagram depicting laser cut tapering
  • Lasers  have a non-zero kerf (cut width), which may affect the final dimensions of your part
  • The laser will heat up your material, which depending on material type may produce visible charring (and even flames!).
  • if your parts will require origami-like folding to assemble after cutting, it may be a good candidate for being made on a 3D printer instead. Laser cutters are generally preferred for flat objects, with complex geometry in only 2 dimensions.

Also consider the material that you are planning to cut, and how it will be used in your project. Some materials that laser cut very well (Like acrylic) are very brittle, and may shatter when flexed or put under a large load.

Step 1: Design your part and export

Use your CAD software of choice to design your part. We recommend Solidworks, Inventor/ Fusion 360, or Sketchup for engineering/mechanical parts, and Adobe Illustrator, or Inkscape for artistic parts. Keep in mind the kerf width of the laser cutter when designing your part, as holes and other features might be oversized if you don’t compensate for this.

If you are using Engineering CAD, create a drawing, and remove all borders and text boxes. Load your part(s) in, and make sure that the scale is set to 1:1. This will screw up your parts otherwise. When you are finished, export your drawing as a .pdf. You now need to transition your part to Inkscape or AI to export as an .svg.

In AI or Inkscape, design your part or import the .pdf you created earlier. When you’re ready to cut, make sure your object is not in any groups (select all, right click,  ungroup), and set the line widths to less than 0.5 pixels (select all, object, fill and stroke). This ensures that the laser only generates one pass on each line. save it as an .svg to a flash drive.

Step 2: prepare to cut

Plug the flash drive into the desired Laser’s computer, and open Inkscape again. Also open RetinaEngrave if it isn’t already running, and let it open in the background. Go to file, document properties, and change the page size to match your material dimensions. Load your part, and double check that everything is where you want it to be. if you are cutting several copies of your part or have multiple parts, open  these in Inkcape as well and copy them over.  Arrange your parts on the material, and set the different layers by changing the edges to different colors. you can have up to 7 different layers (BLK, R, G, B, C M, Y) . When you are satisfied, hit print. Make sure “Full Spectrum Engineering Driver” is selected for the printer.

Step 3: Run your Laser Cut

Important: if you are not trained/do not have swipe to the laser cutter, get a lab manager to perform this step. This guide only covers this step as an aid to the user.

Swipe in, and make sure the printer is on and all necessary cooling peripherals and air filters are running. Pull up the RetinaEngrave software, your Inkscape layout should appear. you may need to hit the rescan button in the bottom left to detect the machine. Select the vector cut tab at the top of the window. Vector cutting will cut through your entire material, and will only follow the edges of your part.  For each layer you created (most cuts only use 1), select the power and speed settings that are ideal for the cutter you are using, your material type and thickness. see the <Laser Cutter Material Table> to determine what these should be. If your material isn’t listed, make sure it is ok to laser cut by speaking to a lab manager. you may need to do some trial and error to find values that work for your material.

Now we need to home the laser, by hitting the home button in the top toolbar. This step is only required for the P48-36  cutter, the hobby laser does not need to be homed. When the laser is homed, use the fast and slow jog commands to move the laser to the top left corner of your cut. This is where the laser cutter thinks the “origin” is. On the hobby laser, you can also hit Unlock, and move the laser by hand to the start location. remember to lock it afterwards!

Check  the dimensions of your cut in RetinaEngrave to  make sure they will fit within the printer, and are what you expect them to be. Click on Run Perimeter to make sure your laser cut stays on your material. The laser will perform four linear moves, following a bounding box of your print. As long as the box stays on your material, you are good to go.  If necessary, you can also place some weights on your material to prevent it from bowing/shifting around during the cut. make sure they don’t get in the way of the laser, though.

On the P48-36, use the slow Z jog commands to raise and lower the bed until the focus meter touches the focus bar and the top of your material. On the Hobby laser, use the same process, but move the bed manually, via the adjustment disk under the cutter.

Now that all of these steps have been completed, you are ready to cut! hit the Run Job button, and watch the laser cutter do its magic. Make sure to stay by the laser cutter for the entire job, and watch for any issues. if there is a non-crical error (paths missing, wrong speed/power, hit Cancel Job to stop and try again. If anything bad happens (fire, crashing into a weight/edge of the table, etc), hit the E-STOP button!