This is a LEGO Mindstorms 3D printer I made with a 3D pen, and a custom g-code interpiter. Unlike other 3D printers made with LEGO Mindstorms, this one can make models like a conventional 3D printer. It uses four LEGO Mindstorms motors. Three on the motors are for the axis, and the fourth controls the extruder.
I chose the 3D I'm using because it took 1.75 mm filament in spool form, and was quite cheap at around $50 USD(Now It's $31.90 USD!).
The print quality isn't very good in comparison to a conventional 3D printer, but this printer is more of a proof of concept. Also, considering the printer is made with a plastic toy system, the print quality is quite respectable.
Items you'll need:
- ($349 USD)LEGO Mindstorms EV3:
- ($35.80 USD)3D Pen:
- ($50-$100 USD)Extra LEGOs:
- (Free Dollars)G-PARS3:
Step 1: Building
The actual printer is just like any other cartesian 3D printer.
You must have three axis:
- Z (Up and down)
- X (Left and right)
- Y (Forward and backwards)
And you need to have the fourth motor press the extrude button on the 3D pen.
Some building tips:
- Reinforce corners with triangles when possible
- Use smaller gears if you are running a platform along gear racks
- Use the LEGO frames when you can
Step 2: Programming
I plan on making an instructional video, but if you know how to use a computer, you should be able to program your EV3 brick with text instructions.
How to install G-PARS3:
- Go to ROBOTC.net and download the latest version of ROBOTC for LEGO MINDSTORMS.
- Follow the install procedure and open the application.
- Go to GitHub.com/cyruscuenca/g-pars3 and download the latest version of G-PARS3.
- G-PARS3 will download as a .zip file, so next, you'll need to extract the file to your Desktop or some other folder. Just be sure to remember where it is.
- Open the folder you extracted, and navigate to > programs > 3D Printer 2.c
- Open the file in ROBOTC
- Next click on "Robot" in the menu, click on "Platform Type", and select EV3.
- Then, still in the "Robot: menu, click "Download EV3 Linux Kernel" and select the standard file.
- Next, in the "Robot" menu, click "Download Firmware", and select the standard file as well.
- Finally, click "Download to Robot".
Calibration instructions are regularly updated, so I keep them here.
How to print your model:
- Obtain your .stl or other standard 3D model file, either by design, or by download. I would recommend thingiverse.com as a reputable 3D model source.
- Open your file in a slicing program. I would recommend Slic3r. I've been using it, and it's given me no problems.
- Scale your model to fit your build area.
- Change the layer thickness and nozzle diameter to to .9.
- Export as "gcode.txt" to your Desktop.
- Plug your EV3 brick into your computor via USB.
- Open "Robot" once again in the ROBOTC application, click "LEGO Brick", then click "File Management Utility".
- Open the rc-data folder.
- Once open, click download, then select your gcode.txt file and download it to the folder.
- Now, click "Download to Robot", and click run.
NOTE: Once the free trial ends for ROBOTC, you can use the file management tool in LEGO's free programming environment.
- If your 3D pen keeps getting stuck, increase your layer height.
- If your print only has one perimeter, you can select "Spiral Vase" which will remove the layer change seam from when your printer moves along the X axis.