Using the eRockets Prusa i3 MK3 printer
eRockets recently acquired a Prusa i3 MK3 3D printer. The following contains basic hints for getting started on designing and printing rocket parts.
As you get started, Justin and Mark can provide guidance and advice on proper use of the printer and printing 3D objects.
As a first step, review the new user support information provided by https://www.prusa3d.com/new-user-mk3/.
The workflow involves three steps:
1. First acquire the .stl file of the design you wish to print or design the 3D object yourself in CAD/CAM software and export the design to an .stl file.
2. Import the .stl file into slicer software to generate a .gcode file.
3. Use the .gcode file to print the object.
Acquiring existing designs
There are many websites devoted to people sharing 3D designs. One of the more popular sites is Thingiverse.com. Thingiverse provides many rocket related designs including complete rockets, rocket parts, and rocket accessories. The creators who share their designs typically include helpful instructions. All include the .stl files of the 3D objects and some include their original software files (e.g., Fusion 360, SolidWorks) and suggested settings for the slicer software. Just download the .stl files so that they can be accessed in the slicer software.
In addition, there is a shared Google Drive folder Rocketry CAD Folder with designs.
Creating your own designs
There are many good 3D modeling software options each with their own advantages and disadvantages. The he design software must have an ability to export an .stl format file of the 3D object. All design software come with a learning curve, so expect to spend some time.
Fusion 360: From Autodesk, Fusion 360 is a full featured 3D design software with professional grade features. There is a free version that can be used by hobbyists for non-commercial use. Fusion 360:
Available at: https://www.autodesk.com/products/fusion–360/overview
Tutorial: Lars Christensen
Tutorial: Autodesk Fusion 360
Book: Parametric Modeling with Autodesk Fusion 360, 2nd Edition by Randy Shih (available on Amazon)
SolidWorks: SolidWorks is a popular option used by many people.
Available at: https://my.solidworks.com
Learning Resources: Learning Solidworks
Book: Parametric Modeling with SOLIDWORKS 2018, 1st Edition by Paul Shilling and Randy Shih (available on Amazon)
OpenSCAD: OpenSCAD is freely available software that is “old school.” You write code to create the 3D object. The code can be parameterized so that you can scale the object through a parameter pane. The Rocketry Forum has many OpenSCAD generators for various rocket parts and accessories.
It is strongly recommended that as you start learning 3D printing that you use the slicer software recommended by the manufacturer. Prusa3D.com has Prusa i3 MK3 drivers and software. Their current version (2.2.2) includes a customized version of the open source Slic3r software (currently version 1.41.2). You’ll probably find just using the Slic3r software easier to start with then their Prusa Control software.
Slic3r software (i3 MK3 software): Prusa Drivers and Apps
Settings to start (change/adjust as you gain experience):
Print settings: 0.15mm OPTIMAL MK3
Filament: Prusa PLA (or ABS, PETG, etc)
Printer: Original Prusa i3 MK3
Fill Density: 20%
Support: none (unless your model really calls for it)
Start up Slic3r
In the Plater tab, click the add button to load the .gcode file
Double check basic settings on the right of the window
Only use the Print Settings, Filament Settings, or Printer Settings once you gained some experience and knowledge
Click the Slice Now button on the right of the window
Check the Preview pane (bottom center of window) to review the slicing
Click the Export G-code button on the right of the window to save the .gcode file
Currently, the MK3 is setup to print from an SD card. Justin and Mark will work during Spring 2019 to setup a wi-fi based method of sending .gcode files to the printer and provide basic training on how to use the printer.
* Put SD card into the slot on the left of the printer. Note that the contacts of the SD card should be facing you as you insert the card.
* Power on the printer (right side, bottom of power supply).
* Wipe down the PEI spring sheet with 90%+ Isopropyl alcohol.
* Using the menu system, preheat the extruder and bed for the material being used (PLA, ABS, PETG, etc.)
* Once preheated, load filament if not already loaded.
* Using the menu system, load the .gcode from the SD card.
* The printer will go through a start up sequence and then move to printing the file.
* Keep an eye on the print, particularly for the first few layers to make sure it is adhering to the bed.
* When the printer is finished, lift the magnetic PEI sheet off the printer, bend slightly to loosen the print. Remove print and any extraneous filament on the sheet.
Last Update: 2018–12–25