How to 3D Print

The CICS Makerspace at UMass, Amherst currently uses Prusa 3D printers. Below are some instructions for getting started with 3D printing on these printers.

  • Save/export your 3D model as an STL file. More info on STL files is here.
  • Import the STL file into a slicer program that will prepare the 3D object for the printer. We use PrusaSlicer because it plays well with the printers in the makerspace, and it was developed by the same people who make most of our printers. The program is free and worth downloading if you’re going to be printing a lot. There are other options for slicer programs if you’d like to branch out like Orca Slicer, UliMaker Cura, or Slic3r.

  • To set up PrusaSlicer:
    • When you first open PrusaSlicer you’ll be prompted to configure things via the Configuration Wizard.
    • Press “Next” until you reach the “Prusa FFF Technology Printers” page.
    • We have the following printers available for community use:
      • MK4 Family
        • Original Prusa MK4 Input Shaper
          • 0.4 mm nozzle
      • MINI Family
        • Original Prusa MINI & MINI+
          • 0.4 mm nozzle
      • MK3 Family
        • Original Prusa i3 MK3S & MK3S+
          • 0.4 mm nozzle
    • There are other settings you can choose in the remainder of the wizard. But if you’re ready to get to the next step, then press the “Finish” button.

  • PrusaSlicer translates the STL file into g-code, the language that tells the 3D printer how to move and extrude the plastic. There are a few settings here that you’ll need to setup. If you’re unsure what to do, you can leave the default settings as they are. Here are some good defaults that we suggest for most prints:
    • Print settings: 0.20mm SPEED
    • Filament: Generic PLA
    • Printer: (set this to the type of printer you’re going to use, like “Original Prusa i3 MK3S & MK3S+”)
    • Supports: (this helps support overhangs or roofs)
    • Infill: 15%
  • We generally use PLA plastics to print. It’s a forgiving and easy-to-work-with plastic for getting started in 3D printing. 
  • Hit the “Slice Now” button in the lower right to translate the STL to g-code!

  • You can inspect the rendering of the 3D object as a toolpath or find out specifics about how the object is going to print here. The time and materials used are listed in the lower right of the screen.
  • Grab the SD card or USB flash drive from the printer you’re going to use. Place it in the computer running PrusaSlicer.
  • When you’re ready, press the “Export G-code” button in the lower right to put the g-code on the removable media.

  • Transfer the flash drive (USB thumb drive, SD card, etc.) to the printer. The printer should walk you through the rest of the steps from there. We have lovely staff that are happy to assist you if you get stuck or have any questions.
  • The printers will have a way to show you how much time remains on your print. If your print finishes before you’re back in the makerspace, then we’ll place it in our Print Pick Up box for you to retrieve later.
  • If your print fails, or doesn’t meet your needs, you can recycle the plastic in our Print Graveyard, which is usually located near the printers. We reuse the plastic so that someone else can make awesome stuff from your creations!

  • To remove your print after it has completed:
    • lift the metal plate with your print on it
    • gently bend the plate so the print releases
    • then snap off the rest of the print
    • excess PLA, like the skirt or supports can be placed in the Print Graveyard under the printers for recycling
    • if your print failed or you will be discarding it, please recycle it in the box under the printers.
  • Spray some isopropyl alcohol on the print bed to remove oils that may have accumulated.
  • You’re all done! Congratulations on successfully 3D printing!